v1.0.8

- Added new output format: `m4b`, enabling chapter metadata in audiobooks. Special thanks to @jborza for implementing this feature in PR #10.
- Better approach for determining the correct configuration folder for Linux and MacOS, using platformdirs. (Fixes Docker issue #12)
- Improvements in documentation and code.

CHANGELOG.md

@@ -1,6 +1,71 @@
-- Merge pull request [#7](https://github.com/denizsafak/abogen/pull/7) by [@jborza](https://github.com/jborza) that improves voice preview and documentation.
+# v1.0.8
+- Added support for AMD GPUs in Linux (Special thanks to @hg000125 for his contribution in #23)
+- Added voice preview caching system that stores generated previews in the cache folder, mentioned by @jborza in #22
+- Added extra metadata support for chaptered M4B files, ensuring better compatibility with audiobook players.
+- Added new option: `Separate chapters audio format`, allowing to choose between `wav`, `mp4`, `flac` and `opus` formats for chaptered audio files.
+- Added a download tracker that displays informative messages while downloading Kokoro models or voices from HuggingFace.
+- Skipping PyTorch CUDA installation if GPU is not NVIDIA in WINDOWS_INSTALL.bat script, preventing unnecessary installation of PyTorch.
+- Removed `abogen_` prefix that was adding to converted books in temp directory.
+- Fixed voice preview player keeps playing silently at the background after preview ends.
+- Fixed not writing separate chapters audio when output is OPUS.
+- Improved input box background color handling, fixed display issues in Linux.
+- Updated profile and voice mixer icons, better visibility and aesthetics in voice mixer.
+- Better sleep state handling for Linux.
+- Improvements in documentation and code.
+
+# v1.0.7
+- Improve chaptered audio generation by outputting directly as `m4b` instead of converting from `wav`.
+- Ignore chapter markers and single newlines when calculating text length, improving the accuracy of the text length calculation.
+- Prevent cancellation if process is at 99%, ensuring the process is not interrupted at the last moment.
+- Improved process handling for subpprocess calls, ensuring better management of subprocesses.
+- Improved PDF handling, ignoring empty pages/chapters and better chapter handling.
+- Added `Save in a project folder with metadata` option in the book handler, allowing users to save the converted items in a project folder with available metadata files. Useful if you want to work with the converted files in the future, issue mentioned by @Darthagnon in #15
+- Added `Go to folder` button in input box, allowing users to open the folder containing the converted file.
+- Added `.opus` as output format for generated audio files, which is a more efficient format for audio files.
+- Added `Create desktop shortcut and install` option to Linux version, allowing users to create a shortcut and install 
+- Added "Playing..." indicator for "Preview" button in the voice mixer.
+
+# v1.0.6
+- Added `Insert chapter marker` button in text editor to insert chapter markers at the current cursor position.
+- Added `Preview` button in voice mixer to preview the voice mix with the selected settings.
+- Fixed `f-string: unmatched '['` error in Voice preview, mentioned in #14
+- Fixed the issue with the content before first chapter not being included in the output.
+- Fixed m4b chapter generation opens CMD window in Windows.
+
+# v1.0.5
+- Added new output format: `m4b`, enabling chapter metadata in audiobooks. Special thanks to @jborza for implementing this feature in PR #10.
+- Better approach for determining the correct configuration folder for Linux and MacOS, using platformdirs. (Fixes Docker issue #12)
+- Improvements in documentation and code.
+
+# v1.0.4
+- Merge pull request [#7](https://github.com/denizsafak/abogen/pull/7) by @jborza that improves voice preview and documentation.
 - Fixed the issue when a voice is selected, the voice mixer tries to pre-select that voice and ignores existing profiles.
 - Fixed the error while renaming the default "New profile" in the voice mixer.
 - Fixed subtitle_combo enabling/disabling when a voice in the voice mixer is selected.
 - Prevented using special characters in the profile name to avoid conflicts.
-- Improved invalid profile handling in the voice mixer.
+- Improved invalid profile handling in the voice mixer.
+
+# v1.0.3
+- Added voice mixing, allowing multiple voices to be combined into a single “Mixed Voice”, a feature mentioned by @PulsarFTW in #1. Special thanks to @jborza for making this possible through his contributions in #5.
+- Added profile system to voice mixer, allowing users to create and manage multiple voice profiles.
+- Improvements in the voice mixer, mostly for organizing controls and enhancing user experience.
+- Added icons for flags and genders in the GUI, making it easier to identify different options.
+- Improved the content and chapter extraction process for EPUB files, ensuring better handling of various structures.
+- Switched to platformdirs for determining the correct desktop path, instead of using old methods.
+- Fixed preview voices was not using GPU acceleration, which was causing performance issues.
+- Improvements in code and documentation.
+
+# v1.0.2
+- Enhanced EPUB handling by treating all items in chapter list (including anchors) as chapters, improving navigation and organization for poorly structured books, mentioned by @Darthagnon in #4
+- Fixed the issue with some chapters in EPUB files had missing content.
+- Fixed the issue with some EPUB files only having one chapter caused the program to ignore the entire book.
+- Fixed "utf-8' codec can't decode byte" error, mentioned by @nigelp in #3
+- Added "Replace single newlines with spaces" option in the menu. This can be useful for texts that have imaginary line breaks.
+- Improvements in code and documentation.
+
+# v1.0.1
+- Added abogen-cli command for better troubleshooting and error handling.
+- Switched from setuptools to hatchling for packaging.
+- Added classifiers to the package metadata.
+- Fixed "No module named 'docopt'" and "setuptools.build_meta" import errors while using .bat installer in Windows, mentioned by @nigelp in #2
+- Improvements in code and documentation.

README.md

@@ -2,7 +2,7 @@
 
 [![Build Status](https://github.com/denizsafak/abogen/actions/workflows/test_pip.yml/badge.svg)](https://github.com/denizsafak/abogen/actions)
 [![GitHub Release](https://img.shields.io/github/v/release/denizsafak/abogen)](https://github.com/denizsafak/abogen/releases/latest)
-![abogen PyPi Python Versions](https://img.shields.io/pypi/pyversions/abogen)
+[![Abogen PyPi Python Versions](https://img.shields.io/pypi/pyversions/abogen)](https://pypi.org/project/abogen/)
 [![Operating Systems](https://img.shields.io/badge/os-windows%20%7C%20linux%20%7C%20macos%20-blue)](https://github.com/denizsafak/abogen/releases/latest)
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 [![License: MIT](https://img.shields.io/badge/License-MIT-maroon.svg)](https://opensource.org/licenses/MIT)
@@ -14,16 +14,18 @@ Abogen is a powerful text-to-speech conversion tool that makes it easy to turn e
 ## Demo
 https://github.com/user-attachments/assets/cb66512d-0a52-48c3-bda4-f1e6a03fb8d6
 
-
 > This demo was generated in just 5 seconds, producing ∼1 minute of audio with perfectly synced subtitles. To create a similar video, see [the demo guide](https://github.com/denizsafak/abogen/tree/main/demo).
 
-## `How to install?`
+## `How to install?` <a href="https://pypi.org/project/abogen/" target="_blank"><img src="https://img.shields.io/pypi/pyversions/abogen" alt="Abogen Compatible PyPi Python Versions" align="right" style="margin-top:6px;"></a>
 ### Windows
 Go to [espeak-ng latest release](https://github.com/espeak-ng/espeak-ng/releases/latest) download and run the *.msi file.
 ```bash
 # For NVIDIA GPUs:
 pip install torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu128
 
+# For AMD GPUs:
+# Not supported yet, because ROCm is not available on Windows. Use Linux if you have AMD GPU.
+
 # Install abogen
 pip install abogen
 ```
@@ -55,14 +57,30 @@ sudo dnf install espeak-ng
 
 # Install abogen
 pip install abogen
+
+# For NVIDIA GPUs:
+# Already supported, no need to install CUDA separately.
+
+# For AMD GPUs:
+pip uninstall torch # After installing abogen, we need to uninstall the existing torch package
+pip install --pre torch torchvision torchaudio --index-url https://download.pytorch.org/whl/nightly/rocm6.4
 ```
+> If you get `WARNING: The script abogen-cli is installed in '/home/username/.local/bin' which is not on PATH.` error, run the following command to add it to your PATH:
+>```bash
+>echo "export PATH=\"/home/$USER/.local/bin:\$PATH\"" >> ~/.bashrc && source ~/.bashrc
+>```
+
 > If you get "No matching distribution found" error, try installing it on supported Python (3.10 to 3.12). You can use [pyenv](https://github.com/pyenv/pyenv) to manage multiple Python versions easily in Linux. Watch this [video](https://www.youtube.com/watch?v=MVyb-nI4KyI) by NetworkChuck for a quick guide.
 
-Then simply run by typing:
+> Special thanks to [@hg000125](https://github.com/hg000125) for his contribution in [#23](https://github.com/denizsafak/abogen/issues/23). AMD GPU support is possible thanks to his work.
+
+## `How to run?`
+If you installed using pip, you can simply run the following command to start Abogen:
 
 ```bash
 abogen
 ```
+> If you installed using the Windows installer `(WINDOWS_INSTALL.bat)`, It should have created a shortcut in the same folder, or your desktop. You can run it from there. If you lost the shortcut, Abogen is located in `python_embedded/Scripts/abogen.exe`. You can run it from there directly.
 
 ## `How to use?`
 1) Drag and drop any ePub, PDF, or text file (or use the built-in text editor)
@@ -85,16 +103,19 @@ Here’s Abogen in action: in this demo, it processes ∼3,000 characters of tex
 - **Voices**: First letter of the language code (e.g., `a` for American English, `b` for British English, etc.), second letter is for `m` for male and `f` for female.
 - **Voice mixer**: Create custom voices by mixing different voice models with a profile system.
 - **Generate subtitles**: `Disabled`, `Sentence`, `Sentence + Comma`, `1 word`, `2 words`, `3 words`, etc. (Represents the number of words in each subtitle entry)
-- **Output formats**: `.WAV`, `.FLAC`, or `.MP3`
+- **Output formats**: `.WAV`, `.FLAC`, `.MP3`, `.OPUS` and `M4B (with chapters)` (Special thanks to [@jborza](https://github.com/jborza) for chapter support in PR [#10](https://github.com/denizsafak/abogen/pull/10))
 - **Save location**: `Save next to input file`, `Save to desktop`, or `Choose output folder`
 - **Chapter Control**: Select specific `chapters` from ePUBs or `chapters + pages` from PDFs.
+- **Save each chapter separately**: Save each chapter in e-books as a separate audio file.
+- **Project folder**: Save the converted items in a project folder with available metadata files.
 - **Options**:
     - **Replace single newlines with spaces**: Replaces single newlines with spaces in the text. This is useful for texts that have imaginary line breaks.
-    - **Configure max words per subtitle**: Automatically configures the maximum number of words per subtitle entry.
+    - **Configure max words per subtitle**: Configures the maximum number of words per subtitle entry.
+    - **Separate chapters audio format**: Configures the audio format for separate chapters (e.g., `WAV`, `FLAC`, `MP3`, `OPUS`).
     - **Create desktop shortcut**: Creates a shortcut on your desktop for easy access.
     - **Open config.json directory**: Opens the directory where the configuration file is stored.
     - **Open temp directory**: Opens the temporary directory where converted text files are stored.
-    - **Clear all temporary files**: Deletes all temporary files created during the conversion process.
+    - **Clear temporary files**: Deletes temporary files created during the conversion or preview.
     - **Check for updates at startup**: Automatically checks for updates when the program starts.
 - **After conversion**: `Open file`, `Go to folder`, `New conversion`, or `Go back`.
 
@@ -103,6 +124,30 @@ Here’s Abogen in action: in this demo, it processes ∼3,000 characters of tex
 
 With voice mixer, you can create custom voices by mixing different voice models. You can adjust the weight of each voice and save your custom voice as a profile for future use. The voice mixer allows you to create unique and personalized voices. (Huge thanks to [@jborza](https://github.com/jborza) for making this possible through his contributions in [#5](https://github.com/denizsafak/abogen/pull/5))
 
+## `About Chapter Markers`
+When you process ePUB or PDF files, Abogen converts them into text files stored in your temporary directory. When you click "Edit," you're actually modifying these converted text files. In these text files, you'll notice tags that look like this:
+
+```
+<<CHAPTER_MARKER:Chapter Title>>
+```
+These are chapter markers. They are automatically added when you process ePUB or PDF files, based on the chapters you select. They serve an important purpose:
+-  Allow you to split the text into separate audio files for each chapter
+-  Save time by letting you reprocess only specific chapters if errors occur, rather than the entire file
+
+You can manually add these markers to plain text files for the same benefits. Simply include them in your text like this:
+
+```
+<<CHAPTER_MARKER:Introduction>>
+This is the beginning of my text...  
+
+<<CHAPTER_MARKER:Main Content>> 
+Here's another part...  
+```
+When you process the text file, Abogen will detect these markers automatically and ask if you want to save each chapter separately and create a merged version.
+
+![Abogen Chapter Marker](https://raw.githubusercontent.com/denizsafak/abogen/refs/heads/main/demo/chapter_marker.png)
+
+
 ## `Supported Languages`
 ```
 # 🇺🇸 'a' => American English, 🇬🇧 'b' => British English
@@ -131,19 +176,56 @@ audio-samplerate=48000
 volume-max=200
 ```
 
+## `Docker Guide`
+If you want to run Abogen in a Docker container:
+1) [Download the repository](https://github.com/denizsafak/abogen/archive/refs/heads/main.zip) and extract, or clone it using git.
+2) Go to `abogen` folder. You should see `Dockerfile` there.
+3) Open your termminal in that directory and run the following commands:
+
+```bash
+# Build the Docker image:
+docker build --progress plain -t abogen .
+
+# Note that building the image may take a while.
+# After building is complete, run the Docker container:
+
+# Windows
+docker run --name abogen -v %cd%:/shared -p 5800:5800 -p 5900:5900 --gpus all abogen
+
+# Linux
+docker run --name abogen -v $(pwd):/shared -p 5800:5800 -p 5900:5900 --gpus all abogen
+
+# MacOS
+docker run --name abogen -v $(pwd):/shared -p 5800:5800 -p 5900:5900 abogen
+
+# We expose port 5800 for use by a web browser, 5900 if you want to connect with a VNC client.
+```
+
+Abogen launches automatically inside the container. 
+- You can access it via a web browser at [http://localhost:5800](http://localhost:5800) or connect to it using a VNC client at `localhost:5900`.
+- You can use `/shared` directory to share files between your host and the container.
+- For later use, start it with `docker start abogen` and stop it with `docker stop abogen`.
+
+Known issues:
+- Audio preview is not working inside container (ALSA error).
+- `Open temp directory` and `Open configuration directory` options in settings not working. (Tried pcmanfm, did not work with Abogen).
+
+(Special thanks to [@geo38](https://www.reddit.com/user/geo38/) from Reddit, who provided the Dockerfile and instructions in [this comment](https://www.reddit.com/r/selfhosted/comments/1k8x1yo/comment/mpe0bz8/).)
+
 ## `Similar Projects`
 Abogen is a standalone project, but it is inspired by and shares some similarities with other projects. Here are a few:
 - [audiblez](https://github.com/santinic/audiblez): Generate audiobooks from e-books. **(Has CLI and GUI support)**
 - [autiobooks](https://github.com/plusuncold/autiobooks): Automatically convert epubs to audiobooks
 - [pdf-narrator](https://github.com/mateogon/pdf-narrator): Convert your PDFs and EPUBs into audiobooks effortlessly.
 - [epub_to_audiobook](https://github.com/p0n1/epub_to_audiobook): EPUB to audiobook converter, optimized for Audiobookshelf
+- [ebook2audiobook](https://github.com/DrewThomasson/ebook2audiobook): Convert ebooks to audiobooks with chapters and metadata using dynamic AI models and voice cloning
 
 ## `Roadmap`
-- [ ] Improve PDF support for better text extraction.
+- [ ] Add OCR scan feature for PDF files using docling.
-- [ ] Add chapter metadata for .m4a files using ffmpeg-bin.
+- [x] Add chapter metadata for .m4a files. (Issue [#9](https://github.com/denizsafak/abogen/issues/9), PR [#10](https://github.com/denizsafak/abogen/pull/10))
 - [ ] Add support for different languages in GUI.
-- [x] Add voice formula feature that enables mixing different voice models. #1
+- [x] Add voice formula feature that enables mixing different voice models. (Issue [#1](https://github.com/denizsafak/abogen/issues/1), PR [#5](https://github.com/denizsafak/abogen/pull/5))
-- [ ] Add support for kokoro-onnx.
+- [ ] Add support for kokoro-onnx (If it's necessary).
 - [ ] Add dark mode.
 
 ## `Troubleshooting`
@@ -171,7 +253,7 @@ Feel free to explore the code and make any changes you like.
 - Thanks to [@wojiushixiaobai](https://github.com/wojiushixiaobai) for [Embedded Python](https://github.com/wojiushixiaobai/Python-Embed-Win64) packages. These modified packages include pip pre-installed, enabling Abogen to function as a standalone application without requiring users to separately install Python in Windows.
 - Thanks to creators of [EbookLib](https://github.com/aerkalov/ebooklib), a Python library for reading and writing ePub files, which is used for extracting text from ePub files.
 - Special thanks to the [PyQt](https://www.riverbankcomputing.com/software/pyqt/) team for providing the cross-platform GUI toolkit that powers Abogen's interface.
-- Icons: [US](https://icons8.com/icon/aRiu1GGi6Aoe/usa), [Great Britain](https://icons8.com/icon/t3NE3BsOAQwq/great-britain), [Spain](https://icons8.com/icon/ly7tzANRt33n/spain), [France](https://icons8.com/icon/3muzEmi4dpD5/france), [India](https://icons8.com/icon/esGVrxg9VCJ1/india), [Italy](https://icons8.com/icon/PW8KZnP7qXzO/italy), [Japan](https://icons8.com/icon/McQbrq9qaQye/japan), [Brazil](https://icons8.com/icon/zHmH8HpOmM90/brazil), [China](https://icons8.com/icon/Ej50Oe3crXwF/china), [Female](https://icons8.com/icon/uI49hxbpxTkp/female), [Male](https://icons8.com/icon/12351/male) and [Voice Id](https://icons8.com/icon/GskSeVoroQ7u/voice-id) icons by [Icons8](https://icons8.com/).
+- Icons: [US](https://icons8.com/icon/aRiu1GGi6Aoe/usa), [Great Britain](https://icons8.com/icon/t3NE3BsOAQwq/great-britain), [Spain](https://icons8.com/icon/ly7tzANRt33n/spain), [France](https://icons8.com/icon/3muzEmi4dpD5/france), [India](https://icons8.com/icon/esGVrxg9VCJ1/india), [Italy](https://icons8.com/icon/PW8KZnP7qXzO/italy), [Japan](https://icons8.com/icon/McQbrq9qaQye/japan), [Brazil](https://icons8.com/icon/zHmH8HpOmM90/brazil), [China](https://icons8.com/icon/Ej50Oe3crXwF/china), [Female](https://icons8.com/icon/uI49hxbpxTkp/female), [Male](https://icons8.com/icon/12351/male), [Adjust](https://icons8.com/icon/21698/adjust) and [Voice Id](https://icons8.com/icon/GskSeVoroQ7u/voice-id) icons by [Icons8](https://icons8.com/).
 
 ## `License`
 This project is available under the MIT License - see the [LICENSE](https://github.com/denizsafak/abogen/blob/main/LICENSE) file for details.

WINDOWS_INSTALL.bat

@@ -219,15 +219,33 @@ if errorlevel 1 (
     exit /b
 )
 
+:: Install progress's fixed version
+echo Installing fixed version of progress...
+%PYTHON_CONSOLE_PATH% -m pip install --force-reinstall https://github.com/denizsafak/abogen/raw/refs/heads/main/abogen/resources/progress-1.6-py3-none-any.whl --no-warn-script-location
+if errorlevel 1 (
+    echo Failed to install fixed version of progress.
+    pause
+    exit /b
+)
+
 :: Install setup requirements
 echo Installing setup requirements...
-%PYTHON_CONSOLE_PATH% -m pip install --upgrade setuptools wheel sphinx hatchling --no-warn-script-location
+%PYTHON_CONSOLE_PATH% -m pip install --upgrade setuptools setuptools-scm wheel sphinx hatchling --no-warn-script-location
 if errorlevel 1 (
     echo Failed to install setup requirements.
     pause
     exit /b
 )
 
+:: Install gpustat
+echo Installing gpustat...
+%PYTHON_CONSOLE_PATH% -m pip install gpustat --no-warn-script-location
+if errorlevel 1 (
+    echo Failed to install gpustat.
+    pause
+    exit /b
+)
+
 :: Install project and dependencies from pyproject.toml
 echo Checking and installing project dependencies...
 if exist %PYPROJECT_FILE% (
@@ -254,21 +272,28 @@ if "%MISAKI_LANG%" NEQ "en" (
     )
 )
 
+:: Check for NVIDIA GPU via is_nvidia()
+for /f %%i in ('%PYTHON_CONSOLE_PATH% -c "from abogen.is_nvidia import check; print(check())"') do set IS_NVIDIA=%%i
+
 :: Check if torch is installed with CUDA support
 echo Checking CUDA availability...
-for /f %%i in ('%PYTHON_CONSOLE_PATH% -c "from torch.cuda import is_available; print(is_available())"') do set cuda_available=%%i
+if /I "%IS_NVIDIA%"=="true" (
+    for /f %%i in ('%PYTHON_CONSOLE_PATH% -c "from torch.cuda import is_available; print(is_available())"') do set cuda_available=%%i
 
-if "%cuda_available%"=="False" (
+    if "%cuda_available%"=="False" (
-    echo Installing PyTorch with CUDA %CUDA_VERSION% support...
+        echo Installing PyTorch with CUDA %CUDA_VERSION% support...
-    %PYTHON_CONSOLE_PATH% -m pip install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu%CUDA_VERSION% --no-warn-script-location
+        %PYTHON_CONSOLE_PATH% -m pip install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu%CUDA_VERSION% --no-warn-script-location
-    echo.
+        echo.
-    if errorlevel 1 (
+        if errorlevel 1 (
-        echo Failed to install PyTorch.
+            echo Failed to install PyTorch.
-        pause
+            pause
-        exit /b
+            exit /b
+        )
+    ) else (
+        echo CUDA is available on NVIDIA GPU.
     )
 ) else (
-    echo CUDA is available.
+    echo GPU is not NVIDIA. Skipping PyTorch CUDA installation.
 )
 
 :: Ask user if they want to create a desktop shortcut

abogen/Dockerfile

@@ -0,0 +1,42 @@
+# Special thanks to @geo38 from Reddit, who provided this Dockerfile:
+# https://www.reddit.com/r/selfhosted/comments/1k8x1yo/comment/mpe0bz8/
+
+# Use a docker base image that runs a window manager that can be viewed
+# outside the image with a web browser or VNC client.
+# https://github.com/jlesage/docker-baseimage-gui
+FROM jlesage/baseimage-gui:debian-12-v4
+
+# Load stuff needed by abogen
+RUN apt-get update \
+ && apt-get install -y \
+        python3 \
+        python3-venv \
+        python3-pip \
+        python3-pyqt5 \
+        espeak-ng \
+ && apt-get clean \
+ && rm -rf /var/lib/apt/lists/*
+
+# The base image will run /startapp.sh on launch.
+#
+# The base image runs that script as user 'app' uid=1000. That user
+# does not exist in the base image but is created at run time.
+#
+# We need to install abogen in python venv (requirement of newer python3).
+#
+# The python venv has to be writable by the 'app' user as abogen dynamically
+# installs python packages, so create the venv as that user
+#
+# We intend to share the /shared directory with the host using a bind volume
+# in order to access any source files and the created files.
+
+RUN echo '#!/bin/bash\nsource /app/venv/bin/activate\nexec abogen' > /startapp.sh \
+  && chmod 555 /startapp.sh \
+  && mkdir /app /shared \
+  && chown 1000:1000 /app /shared \
+  && chmod 755 /app /shared
+USER 1000:1000
+RUN python3 -m venv /app/venv
+RUN /bin/bash -c "source /app/venv/bin/activate && pip install abogen"
+# Change back to user ROOT as the startup scripts inside base image needs it
+USER root

abogen/VERSION

@@ -1 +1 @@
-1.0.4
+1.0.8

abogen/book_handler.py

@@ -37,6 +37,7 @@ class HandlerDialog(QDialog):
     # Class variables to remember checkbox states between dialog instances
     _save_chapters_separately = False
     _merge_chapters_at_end = True
+    _save_as_project = False  # New class variable for save_as_project option
 
     def __init__(self, book_path, file_type=None, checked_chapters=None, parent=None):
         super().__init__(parent)
@@ -64,6 +65,7 @@ class HandlerDialog(QDialog):
         # Initialize save chapters flags from class variables
         self.save_chapters_separately = HandlerDialog._save_chapters_separately
         self.merge_chapters_at_end = HandlerDialog._merge_chapters_at_end
+        self.save_as_project = HandlerDialog._save_as_project
 
         # Load the book based on file type
         try:
@@ -934,6 +936,7 @@ class HandlerDialog(QDialog):
     def _build_pdf_tree(self):
         outline = self.pdf_doc.get_toc()
         self.has_pdf_bookmarks = bool(outline)
+        self.bookmark_items_map = {}
 
         if not outline:
             self._build_pdf_pages_tree()
@@ -976,20 +979,23 @@ class HandlerDialog(QDialog):
                         else self.pdf_doc.resolve_link(page)[0]
                     )
                     page_id = f"page_{page_num+1}"
-
+                    # attach chapters on same page under original
+                    if page_num in self.bookmark_items_map:
+                        orig = self.bookmark_items_map[page_num]
+                        child = QTreeWidgetItem(orig, [f"{title} (Same page)"])
+                        child.setData(0, Qt.UserRole, page_id)
+                        child.setFlags(child.flags() & ~Qt.ItemIsUserCheckable)
+                        continue
                     bookmark_item = QTreeWidgetItem(parent_item, [title])
                     bookmark_item.setData(0, Qt.UserRole, page_id)
-                    bookmark_item.setFlags(
+                    # only allow checking if this chapter has content
-                        bookmark_item.flags() | Qt.ItemIsUserCheckable
+                    if self.content_lengths.get(page_id, 0) > 0:
-                    )
+                        bookmark_item.setFlags(bookmark_item.flags() | Qt.ItemIsUserCheckable)
-                    bookmark_item.setCheckState(
+                        bookmark_item.setCheckState(0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked)
-                        0,
+                    else:
-                        (
+                        bookmark_item.setFlags(bookmark_item.flags() & ~Qt.ItemIsUserCheckable)
-                            Qt.Checked
+                    # map for uncategorized pages
-                            if page_id in self.checked_chapters
+                    self.bookmark_items_map[page_num] = bookmark_item
-                            else Qt.Unchecked
-                        ),
-                    )
 
                     added_pages.add(page_num)
 
@@ -1012,30 +1018,39 @@ class HandlerDialog(QDialog):
 
                         page_item = QTreeWidgetItem(bookmark_item, [page_title])
                         page_item.setData(0, Qt.UserRole, page_id)
-                        page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
+                        # only allow checking if this sub-page has content
-                        page_item.setCheckState(
+                        if self.content_lengths.get(page_id, 0) > 0:
-                            0,
+                            page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
-                            (
+                            page_item.setCheckState(0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked)
-                                Qt.Checked
+                        else:
-                                if page_id in self.checked_chapters
+                            page_item.setFlags(page_item.flags() & ~Qt.ItemIsUserCheckable)
-                                else Qt.Unchecked
-                            ),
-                        )
 
                         added_pages.add(sub_page_num)
 
-                    if len(entry) > 3 and isinstance(entry[3], list):
-                        build_outline_tree(entry[3], bookmark_item)
-
         build_outline_tree(outline, self.treeWidget)
 
         covered_pages = set(added_pages)
-
+        # attach any pages without direct bookmarks under nearest preceding chapter
-        uncategorized_pages = [
+        uncategorized_pages = [i for i in range(len(self.pdf_doc)) if i not in covered_pages]
-            i for i in range(len(self.pdf_doc)) if i not in covered_pages
+        for page_num in uncategorized_pages:
-        ]
+            # find nearest previous bookmark
-        if uncategorized_pages:
+            prev_nums = [n for n in sorted(self.bookmark_items_map) if n < page_num]
-            self._add_other_pages(uncategorized_pages)
+            parent_item = self.bookmark_items_map[prev_nums[-1]] if prev_nums else self.treeWidget
+            page_id = f"page_{page_num+1}"
+            title = f"Page {page_num+1}"
+            text = self.content_texts.get(page_id, "").strip()
+            if text:
+                first = text.split("\n", 1)[0].strip()
+                if first and len(first) < 100:
+                    title += f" - {first}"
+            page_item = QTreeWidgetItem(parent_item, [title])
+            page_item.setData(0, Qt.UserRole, page_id)
+            # only allow checking if uncategorized page has content
+            if self.content_lengths.get(page_id, 0) > 0:
+                page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
+                page_item.setCheckState(0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked)
+            else:
+                page_item.setFlags(page_item.flags() & ~Qt.ItemIsUserCheckable)
 
     def _build_pdf_pages_tree(self):
         pages_item = QTreeWidgetItem(self.treeWidget, ["Pages"])
@@ -1056,34 +1071,12 @@ class HandlerDialog(QDialog):
 
             page_item = QTreeWidgetItem(pages_item, [page_title])
             page_item.setData(0, Qt.UserRole, page_id)
-            page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
+            # only allow checking if standalone page has content
-            page_item.setCheckState(
+            if self.content_lengths.get(page_id, 0) > 0:
-                0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked
+                page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
-            )
+                page_item.setCheckState(0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked)
-
+            else:
-    def _add_other_pages(self, uncategorized_pages):
+                page_item.setFlags(page_item.flags() & ~Qt.ItemIsUserCheckable)
-        other_pages = QTreeWidgetItem(self.treeWidget, ["Other Pages"])
-        other_pages.setFlags(other_pages.flags() & ~Qt.ItemIsUserCheckable)
-        font = other_pages.font(0)
-        font.setBold(True)
-        other_pages.setFont(0, font)
-
-        for page_num in uncategorized_pages:
-            page_id = f"page_{page_num+1}"
-            page_title = f"Page {page_num+1}"
-
-            page_text = self.content_texts.get(page_id, "").strip()
-            if page_text:
-                first_line = page_text.split("\n", 1)[0].strip()
-                if first_line and len(first_line) < 100:
-                    page_title += f" - {first_line}"
-
-            page_item = QTreeWidgetItem(other_pages, [page_title])
-            page_item.setData(0, Qt.UserRole, page_id)
-            page_item.setFlags(page_item.flags() | Qt.ItemIsUserCheckable)
-            page_item.setCheckState(
-                0, Qt.Checked if page_id in self.checked_chapters else Qt.Unchecked
-            )
 
     def _are_provided_checks_relevant(self):
         if not self.checked_chapters:
@@ -1108,7 +1101,7 @@ class HandlerDialog(QDialog):
         self.previewEdit.setStyleSheet("QTextEdit { border: none; }")
 
         self.previewInfoLabel = QLabel(
-            '*Note: You can modify the content later using the "Edit" button in the input box or by accessing the temporary files directory through settings.',
+            '*Note: You can modify the content later using the "Edit" button in the input box or by accessing the temporary files directory through settings (if not saved in a project folder).',
             self,
         )
         self.previewInfoLabel.setWordWrap(True)
@@ -1182,8 +1175,7 @@ class HandlerDialog(QDialog):
         self.save_chapters_checkbox = QCheckBox(checkbox_text, self)
         self.save_chapters_checkbox.setChecked(self.save_chapters_separately)
         self.save_chapters_checkbox.stateChanged.connect(self.on_save_chapters_changed)
-        leftLayout.addWidget(self.save_chapters_checkbox)
+        leftLayout.addWidget(self.save_chapters_checkbox)        
-
         self.merge_chapters_checkbox = QCheckBox(
             "Create a merged version at the end", self
         )
@@ -1192,6 +1184,19 @@ class HandlerDialog(QDialog):
             self.on_merge_chapters_changed
         )
         leftLayout.addWidget(self.merge_chapters_checkbox)
+        
+        self.save_as_project_checkbox = QCheckBox(
+            "Save in a project folder with metadata", self
+        )
+        self.save_as_project_checkbox.setToolTip(
+            "Save the converted item in a project folder with metadata files. "
+            "(Useful if you want to work with converted items in the future.)"
+        )
+        self.save_as_project_checkbox.setChecked(self.save_as_project)
+        self.save_as_project_checkbox.stateChanged.connect(
+            self.on_save_as_project_changed
+        )
+        leftLayout.addWidget(self.save_as_project_checkbox)
 
         leftLayout.addWidget(buttons)
 
@@ -1489,8 +1494,13 @@ class HandlerDialog(QDialog):
             authors_text = ", ".join(self.book_metadata["authors"])
             html_content += f"<p style='text-align: center; font-style: italic;'>By {authors_text}</p>"
 
-        if self.book_metadata["publisher"]:
+        if self.book_metadata["publisher"] or self.book_metadata.get("publication_year"):
-            html_content += f"<p style='text-align: center;'>Published by {self.book_metadata['publisher']}</p>"
+            pub_info = []
+            if self.book_metadata["publisher"]:
+                pub_info.append(f"Published by {self.book_metadata['publisher']}")
+            if self.book_metadata.get("publication_year"):
+                pub_info.append(f"Year: {self.book_metadata['publication_year']}")
+            html_content += f"<p style='text-align: center;'>{' | '.join(pub_info)}</p>"
 
         html_content += "<hr/>"
 
@@ -1512,24 +1522,51 @@ class HandlerDialog(QDialog):
             "description": None,
             "cover_image": None,
             "publisher": None,
+            "publication_year": None,
         }
 
         if self.file_type == "epub":
-            title_items = self.book.get_metadata("DC", "title")
+            try:
-            if title_items:
+                title_items = self.book.get_metadata("DC", "title")
-                metadata["title"] = title_items[0][0]
+                if title_items and len(title_items) > 0:
+                    metadata["title"] = title_items[0][0]
+            except Exception as e:
+                logging.warning(f"Error extracting title metadata: {e}")
 
-            author_items = self.book.get_metadata("DC", "creator")
+            try:
-            if author_items:
+                author_items = self.book.get_metadata("DC", "creator")
-                metadata["authors"] = [author[0] for author in author_items]
+                if author_items:
+                    metadata["authors"] = [author[0] for author in author_items if len(author) > 0]
+            except Exception as e:
+                logging.warning(f"Error extracting author metadata: {e}")
 
-            desc_items = self.book.get_metadata("DC", "description")
+            try:
-            if desc_items:
+                desc_items = self.book.get_metadata("DC", "description")
-                metadata["description"] = desc_items[0][0]
+                if desc_items and len(desc_items) > 0:
+                    metadata["description"] = desc_items[0][0]
+            except Exception as e:
+                logging.warning(f"Error extracting description metadata: {e}")
 
-            publisher_items = self.book.get_metadata("DC", "publisher")
+            try:
-            if publisher_items:
+                publisher_items = self.book.get_metadata("DC", "publisher")
-                metadata["publisher"] = publisher_items[0][0]
+                if publisher_items and len(publisher_items) > 0:
+                    metadata["publisher"] = publisher_items[0][0]
+            except Exception as e:
+                logging.warning(f"Error extracting publisher metadata: {e}")
+                
+            # Try to extract publication year
+            try:
+                date_items = self.book.get_metadata("DC", "date")
+                if date_items and len(date_items) > 0:
+                    date_str = date_items[0][0]
+                    # Try to extract just the year from the date string
+                    year_match = re.search(r'\b(19|20)\d{2}\b', date_str)
+                    if year_match:
+                        metadata["publication_year"] = year_match.group(0)
+                    else:
+                        metadata["publication_year"] = date_str
+            except Exception as e:
+                logging.warning(f"Error extracting publication date metadata: {e}")
 
             for item in self.book.get_items_of_type(ebooklib.ITEM_COVER):
                 metadata["cover_image"] = item.get_content()
@@ -1559,6 +1596,18 @@ class HandlerDialog(QDialog):
                         metadata["description"] = f"Keywords: {keywords}"
 
                 metadata["publisher"] = pdf_info.get("creator", None)
+                
+                # Try to extract publication date from PDF metadata
+                if "creationDate" in pdf_info:
+                    date_str = pdf_info["creationDate"]
+                    year_match = re.search(r'D:(\d{4})', date_str)
+                    if year_match:
+                        metadata["publication_year"] = year_match.group(1)
+                elif "modDate" in pdf_info:
+                    date_str = pdf_info["modDate"]
+                    year_match = re.search(r'D:(\d{4})', date_str)
+                    if year_match:
+                        metadata["publication_year"] = year_match.group(1)
 
             if len(self.pdf_doc) > 0:
                 try:
@@ -1575,10 +1624,43 @@ class HandlerDialog(QDialog):
         else:
             return self._get_pdf_selected_text()
 
+    def _format_metadata_tags(self):
+        """Format metadata tags for insertion at the beginning of the text"""
+        import datetime
+        
+        metadata = self.book_metadata
+        filename = os.path.splitext(os.path.basename(self.book_path))[0]
+        current_year = str(datetime.datetime.now().year)
+        
+        # Get values with fallbacks
+        title = metadata.get("title") or filename
+        authors = metadata.get("authors") or ["Unknown"]
+        authors_text = ", ".join(authors)
+        album_artist = authors_text or "Unknown"
+        year = metadata.get("publication_year") or current_year  # Use publication year if available
+        
+        # Count chapters/pages
+        total_chapters = len(self.checked_chapters)
+        chapter_text = f"{total_chapters} {'Chapters' if self.file_type == 'epub' else 'Pages'}"
+        
+        # Format metadata tags
+        metadata_tags = [
+            f"<<METADATA_TITLE:{title}>>",
+            f"<<METADATA_ARTIST:{authors_text}>>",
+            f"<<METADATA_ALBUM:{title} ({chapter_text})>>",
+            f"<<METADATA_YEAR:{year}>>",
+            f"<<METADATA_ALBUM_ARTIST:{album_artist}>>"
+        ]
+        
+        return "\n".join(metadata_tags)
+
     def _get_epub_selected_text(self):
         all_checked_identifiers = set()
         chapter_texts = []
 
+        # Add metadata tags at the beginning
+        metadata_tags = self._format_metadata_tags()
+        
         item_order_counter = 0
         ordered_checked_items = []
 
@@ -1603,7 +1685,7 @@ class HandlerDialog(QDialog):
                 marker = f"<<CHAPTER_MARKER:{title}>>"
                 chapter_texts.append(marker + "\n" + text)
 
-        full_text = "\n\n".join(chapter_texts)
+        full_text = metadata_tags + "\n\n" + "\n\n".join(chapter_texts)
         return full_text, all_checked_identifiers
 
     def _get_pdf_selected_text(self):
@@ -1612,6 +1694,9 @@ class HandlerDialog(QDialog):
         section_titles = []
         all_content = []
 
+        # Add metadata tags at the beginning
+        metadata_tags = self._format_metadata_tags()
+
         pdf_has_no_bookmarks = (
             hasattr(self, "has_pdf_bookmarks") and not self.has_pdf_bookmarks
         )
@@ -1636,7 +1721,7 @@ class HandlerDialog(QDialog):
                     if text:
                         all_content.append(text)
                         included_text_ids.add(page_id)
-            return "\n\n".join(all_content), all_checked_identifiers
+            return metadata_tags + "\n\n" + "\n\n".join(all_content), all_checked_identifiers
 
         iterator = QTreeWidgetItemIterator(self.treeWidget)
         while iterator.value():
@@ -1694,7 +1779,7 @@ class HandlerDialog(QDialog):
                         included_text_ids.add(identifier)
             iterator += 1
 
-        return "\n\n".join([t[1] for t in section_titles]), all_checked_identifiers
+        return metadata_tags + "\n\n" + "\n\n".join([t[1] for t in section_titles]), all_checked_identifiers
 
     def on_save_chapters_changed(self, state):
         self.save_chapters_separately = bool(state)
@@ -1705,6 +1790,10 @@ class HandlerDialog(QDialog):
         self.merge_chapters_at_end = bool(state)
         HandlerDialog._merge_chapters_at_end = self.merge_chapters_at_end
 
+    def on_save_as_project_changed(self, state):
+        self.save_as_project = bool(state)
+        HandlerDialog._save_as_project = self.save_as_project
+
     def get_save_chapters_separately(self):
         return (
             self.save_chapters_separately
@@ -1715,6 +1804,9 @@ class HandlerDialog(QDialog):
     def get_merge_chapters_at_end(self):
         return self.merge_chapters_at_end
 
+    def get_save_as_project(self):
+        return self.save_as_project
+
     def on_tree_context_menu(self, pos):
         item = self.treeWidget.itemAt(pos)
         if (

abogen/conversion.py

@@ -4,13 +4,18 @@ import tempfile
 import time
 import chardet
 import charset_normalizer
+import hashlib  # For generating unique cache filenames
 from platformdirs import user_desktop_dir
 from PyQt5.QtCore import QThread, pyqtSignal, Qt
 from PyQt5.QtWidgets import QCheckBox, QVBoxLayout, QDialog, QLabel, QDialogButtonBox
 import soundfile as sf
-from utils import clean_text
+from utils import clean_text, create_process
 from constants import PROGRAM_NAME, LANGUAGE_DESCRIPTIONS, SAMPLE_VOICE_TEXTS
 from voice_formulas import get_new_voice
+import hf_tracker
+import static_ffmpeg
+import threading  # for efficient waiting
+import subprocess
 
 
 def get_sample_voice_text(lang_code):
@@ -128,6 +133,7 @@ class ConversionThread(QThread):
         use_gpu=True,
     ):  # Add use_gpu parameter
         super().__init__()
+        self._chapter_options_event = threading.Event()
         self.np = np_module
         self.KPipeline = kpipeline_class
         self.file_name = file_name
@@ -156,6 +162,7 @@ class ConversionThread(QThread):
             f"\nVoice: {self.voice}\nLanguage: {self.lang_code}\nSpeed: {self.speed}\nGPU: {self.use_gpu}\nFile: {self.file_name}\nSubtitle mode: {self.subtitle_mode}\nOutput format: {self.output_format}\nSave option: {self.save_option}\n"
         )
         try:
+            hf_tracker.set_log_callback(lambda msg: self.log_updated.emit(msg))
             # Show configuration
             self.log_updated.emit("Configuration:")
             # Use display_path for logs if available, otherwise use the actual file name
@@ -192,6 +199,9 @@ class ConversionThread(QThread):
                     self.log_updated.emit(
                         f"- Merge chapters at the end: {'Yes' if merge_at_end else 'No'}"
                     )
+                    # Display the separate chapters format if it's set
+                    separate_format = getattr(self, 'separate_chapters_format', 'wav')
+                    self.log_updated.emit(f"- Separate chapters format: {separate_format}")
 
             if self.save_option == "Choose output folder":
                 self.log_updated.emit(
@@ -216,12 +226,22 @@ class ConversionThread(QThread):
 
             # Clean up text using utility function
             text = clean_text(text)
+            
+            # Remove metadata markers from the text to be processed
+            metadata_pattern = r"<<METADATA_[^:]+:[^>]*>>"
+            text = re.sub(metadata_pattern, "", text)
 
             # --- Chapter splitting logic ---
             chapter_pattern = r"<<CHAPTER_MARKER:(.*?)>>"
             chapter_splits = list(re.finditer(chapter_pattern, text))
             chapters = []
             if chapter_splits:
+                # prepend Introduction for content before first marker
+                first_start = chapter_splits[0].start()
+                if first_start > 0:
+                    intro_text = text[:first_start].strip()
+                    if intro_text:
+                        chapters.append(("Introduction", intro_text))
                 for idx, match in enumerate(chapter_splits):
                     start = match.end()
                     end = (
@@ -252,18 +272,12 @@ class ConversionThread(QThread):
                 and not self.chapter_options_set
             ):
 
-                self.waiting_for_user_input = True
+                # Emit signal to main thread and wait
-                # Emit signal to main thread to show dialog
                 self.chapters_detected.emit(total_chapters)
-
+                self._chapter_options_event.wait()
-                # Wait for chapter options to be set
-                while self.waiting_for_user_input and not self.cancel_requested:
-                    time.sleep(0.1)
-
                 if self.cancel_requested:
                     self.conversion_finished.emit("Cancelled", None)
                     return
-
                 self.chapter_options_set = True
 
             # Log all detected chapters at the beginning
@@ -339,6 +353,12 @@ class ConversionThread(QThread):
             # Initialize current segment counter
             current_segment = 0
 
+            # Initialize chapter times
+            chapters_time = [
+                {"chapter": chapter[0], "start": 0.0, "end": 0.0}
+                for chapter in chapters
+            ]
+
             # Instead of processing the whole text, process by chapter
             for chapter_idx, (chapter_name, chapter_text) in enumerate(chapters, 1):
                 if total_chapters > 1:
@@ -354,6 +374,10 @@ class ConversionThread(QThread):
                 chapter_subtitle_entries = []
                 chapter_current_time = 0.0
 
+                # chapter start time
+                chapter_time = chapters_time[chapter_idx - 1]
+                chapter_time["start"] = current_time
+
                 # Set split_pattern to \n+ which will split on one or more newlines
                 split_pattern = r"\n+"
 
@@ -467,6 +491,9 @@ class ConversionThread(QThread):
                     # Update progress more frequently (after each result)
                     self.progress_updated.emit(percent, etr_str)
 
+                # Update chapter end time
+                chapter_time["end"] = current_time
+
                 # Save the individual chapter output if save_chapters_separately is enabled
                 if (
                     save_chapters_separately
@@ -483,15 +510,47 @@ class ConversionThread(QThread):
 
                     # Concatenate chapter audio and save
                     chapter_audio = self.np.concatenate(chapter_audio_segments)
+                    
+                    # Use separate_chapters_format
+                    separate_format = getattr(self, 'separate_chapters_format', 'wav')
+                    
                     chapter_out_path = os.path.join(
-                        chapters_out_dir, f"{chapter_filename}.{self.output_format}"
+                        chapters_out_dir, f"{chapter_filename}.{separate_format}"
-                    )
-                    sf.write(
-                        chapter_out_path,
-                        chapter_audio,
-                        24000,
-                        format=self.output_format,
                     )
+                    if separate_format == "opus":
+                        static_ffmpeg.add_paths()
+                        proc = create_process(
+                            [
+                                "ffmpeg",
+                                "-y",
+                                "-thread_queue_size", "32768", # Increased thread_queue_size for chapter opus
+                                "-f",
+                                "f32le",
+                                "-ar",
+                                "24000",
+                                "-ac",
+                                "1",
+                                "-i",
+                                "pipe:0",
+                                "-c:a",
+                                "libopus",
+                                "-b:a",
+                                "24000",
+                                chapter_out_path,
+                            ],
+                            stdin=subprocess.PIPE,
+                            text=False  # Ensure binary stdin for audio data
+                        )
+                        proc.stdin.write(chapter_audio.astype("float32").tobytes())
+                        proc.stdin.close()
+                        proc.wait()
+                    else:
+                        sf.write(
+                            chapter_out_path,
+                            chapter_audio,
+                            24000,
+                            format=separate_format,
+                        )
 
                     # Generate .srt subtitle file for chapter if not Disabled
                     if self.subtitle_mode != "Disabled" and chapter_subtitle_entries:
@@ -531,34 +590,74 @@ class ConversionThread(QThread):
                 or not self.save_chapters_separately
                 or getattr(self, "merge_chapters_at_end", True)
             )
+            
+            intended_output_format = self.output_format # Store the original choice
+
             if audio_segments and merge_chapters:
                 self.log_updated.emit("\nFinalizing audio file...\n")
-                audio = self.np.concatenate(audio_segments)
+                audio_data_np = self.np.concatenate(audio_segments)
+                
                 out_dir = parent_dir
-                # Use the same suffix as above
+                base_filepath_no_ext = os.path.join(out_dir, f"{base_name}{suffix}")
-                out_filename = f"{base_name}{suffix}.{self.output_format}"
+
-                out_path = os.path.join(out_dir, out_filename)
+                final_out_path = None
-                srt_path = os.path.splitext(out_path)[0] + ".srt"
+
-                sf.write(out_path, audio, 24000, format=self.output_format)
+                if intended_output_format == "m4b":
-                if self.subtitle_mode != "Disabled":
+                    final_out_path = self._generate_m4b_with_chapters(audio_data_np, chapters_time, base_filepath_no_ext)
-                    with open(
+                elif intended_output_format == "opus":
-                        srt_path, "w", encoding="utf-8", errors="replace"
+                    static_ffmpeg.add_paths()
-                    ) as srt_file:
+                    opus_out_path = f"{base_filepath_no_ext}.opus"
-                        for i, (start, end, text) in enumerate(subtitle_entries, 1):
+                    ffmpeg_cmd_opus = [
-                            srt_file.write(
+                        "ffmpeg", "-y",
-                                f"{i}\n{self._srt_time(start)} --> {self._srt_time(end)}\n{text}\n\n"
+                        "-thread_queue_size", "32768", # Increased thread_queue_size
-                            )
+                        "-f", "f32le", "-ar", "24000", "-ac", "1", "-i", "pipe:0",
-                    self.conversion_finished.emit(
+                        "-c:a", "libopus", "-b:a", "24000", # Original bitrate
-                        (
+                        opus_out_path,
-                            f"Audiobook saved to: {out_path}\n\nSubtitle saved to: {srt_path}",
+                    ]
-                            "green",
+                    try:
-                        ),
+                        process = create_process(ffmpeg_cmd_opus, stdin=subprocess.PIPE, text=False)  # Ensure binary stdin
-                        out_path,
+                        process.stdin.write(audio_data_np.astype("float32").tobytes())
-                    )
+                        process.stdin.close()
+                        if process.wait() == 0:
+                            final_out_path = opus_out_path
+                        else:
+                            self.log_updated.emit(("Opus conversion failed.", "red"))
+                            final_out_path = None 
+                    except Exception as e_opus:
+                        self.log_updated.emit((f"Error during Opus conversion: {str(e_opus)}", "red"))
+                        final_out_path = None
+                else: # For other formats like wav
+                    standard_out_path = f"{base_filepath_no_ext}.{intended_output_format}"
+                    try:
+                        sf.write(standard_out_path, audio_data_np, 24000, format=intended_output_format)
+                        final_out_path = standard_out_path
+                    except Exception as e_sf:
+                        self.log_updated.emit((f"Failed to write audio file {standard_out_path}: {str(e_sf)}", "red"))
+                        final_out_path = None
+
+                # Subtitle and final message logic
+                if final_out_path:
+                    if self.subtitle_mode != "Disabled":
+                        srt_path = os.path.splitext(final_out_path)[0] + ".srt"
+                        with open(srt_path, "w", encoding="utf-8", errors="replace") as srt_file:
+                            for i, (start, end, text) in enumerate(subtitle_entries, 1):
+                                srt_file.write(
+                                    f"{i}\n{self._srt_time(start)} --> {self._srt_time(end)}\n{text}\n\n"
+                                )
+                        self.conversion_finished.emit(
+                            (
+                                f"Audiobook saved to: {final_out_path}\n\nSubtitle saved to: {srt_path}",
+                                "green",
+                            ),
+                            final_out_path,
+                        )
+                    else:
+                        self.conversion_finished.emit(
+                            (f"Audiobook saved to: {final_out_path}", "green"), final_out_path
+                        )
                 else:
-                    self.conversion_finished.emit(
+                    self.log_updated.emit(("Audio generation failed (final_out_path was not set).", "red"))
-                        (f"Audiobook saved to: {out_path}", "green"), out_path
+                    self.conversion_finished.emit(("Audio generation failed.", "red"), None)
-                    )
             elif audio_segments and not merge_chapters:
                 self.conversion_finished.emit(
                     (
@@ -579,6 +678,151 @@ class ConversionThread(QThread):
         self.save_chapters_separately = options["save_chapters_separately"]
         self.merge_chapters_at_end = options["merge_chapters_at_end"]
         self.waiting_for_user_input = False
+        self._chapter_options_event.set()
+
+    def _generate_m4b_with_chapters(self, audio_data_np, chapters_time, base_filepath_no_ext):
+        final_wav_path = f"{base_filepath_no_ext}.wav"
+        
+        if not chapters_time or len(chapters_time) <= 1:
+            self.log_updated.emit(
+                (
+                    "File contains only one chapter or no chapters were detected. Audio will be saved as a standard .wav file instead.\n",
+                    "red",
+                )
+            )
+            try:
+                sf.write(final_wav_path, audio_data_np, 24000, format="wav")
+                return final_wav_path
+            except Exception as e_wav_single:
+                self.log_updated.emit((f"Failed to save single/no chapter audio as WAV: {str(e_wav_single)}", "red"))
+                return None
+
+        output_m4b_path = f"{base_filepath_no_ext}.m4b"
+        chapters_info_path = f"{base_filepath_no_ext}_chapters.txt"
+
+        try:
+            with open(chapters_info_path, "w", encoding="utf-8") as f:
+                f.write(";FFMETADATA1\n")
+                for chapter in chapters_time:
+                    f.write(f"[CHAPTER]\n")
+                    f.write(f"TIMEBASE=1/1000\n") # Using milliseconds for precision
+                    f.write(f"START={int(chapter['start']*1000)}\n")
+                    f.write(f"END={int(chapter['end']*1000)}\n")
+                    f.write(f"title={chapter['chapter']}\n\n")
+
+            static_ffmpeg.add_paths()
+            ffmpeg_cmd = [
+                "ffmpeg", "-y",
+                "-thread_queue_size", "32768", # Increased thread_queue_size
+                "-f", "f32le", "-ar", "24000", "-ac", "1", "-i", "pipe:0",
+                "-i", chapters_info_path,
+                "-map", "0:a",
+                "-map_metadata", "1", 
+                "-map_chapters", "1",
+                # Add metadata tags
+                "-metadata", "composer=Narrator",
+                "-metadata", "genre=Audiobook",
+                # Extract metadata from text markers if available
+                *self._extract_and_add_metadata_tags_to_ffmpeg_cmd(),
+                "-c:a", "aac",
+                "-q:a", "2", # Quality-based VBR for better quality control (lower = better, range 0.1-2)
+                "-movflags", "+faststart+use_metadata_tags",  # Added for better compatibility
+                output_m4b_path,
+            ]
+
+            self.log_updated.emit(f"Generating audio with chapters...\n")
+
+            process = create_process(ffmpeg_cmd, stdin=subprocess.PIPE, text=False)  # Ensure binary stdin
+            process.stdin.write(audio_data_np.astype("float32").tobytes())
+            process.stdin.close()
+            return_code = process.wait()
+
+            if return_code == 0:
+                return output_m4b_path
+            else:
+                self.log_updated.emit(
+                    (f"FFmpeg failed to create M4B (return code {return_code}).\n\nFalling back to WAV.\n", "red")
+                )
+                sf.write(final_wav_path, audio_data_np, 24000, format="wav")
+                return final_wav_path
+
+        except Exception as e:
+            self.log_updated.emit((f"Error during M4B generation: {str(e)}.\n\nFalling back to WAV.\n", "red"))
+            try:
+                sf.write(final_wav_path, audio_data_np, 24000, format="wav")
+                return final_wav_path
+            except Exception as e_wav_fallback:
+                self.log_updated.emit((f"Critical error: Failed to save fallback WAV: {str(e_wav_fallback)}\n", "red"))
+                return None
+        finally:
+            if os.path.exists(chapters_info_path):
+                try:
+                    os.remove(chapters_info_path)
+                except Exception as e_clean:
+                    self.log_updated.emit((f"Warning: Could not delete temporary chapter file {chapters_info_path}: {e_clean}", "orange"))
+
+    def _extract_and_add_metadata_tags_to_ffmpeg_cmd(self):
+        """Extract metadata tags from text content and add them to ffmpeg command"""
+        metadata_options = []
+        
+        # Get the input text (either direct or from file)
+        text = ""
+        if self.is_direct_text:
+            text = self.file_name
+        else:
+            try:
+                encoding = detect_encoding(self.file_name)
+                with open(self.file_name, "r", encoding=encoding, errors="replace") as file:
+                    text = file.read()
+            except Exception as e:
+                self.log_updated.emit(f"Warning: Could not read file for metadata extraction: {e}")
+                return []
+                
+        # Extract metadata tags using regex
+        title_match = re.search(r"<<METADATA_TITLE:([^>]*)>>", text)
+        artist_match = re.search(r"<<METADATA_ARTIST:([^>]*)>>", text) 
+        album_match = re.search(r"<<METADATA_ALBUM:([^>]*)>>", text)
+        year_match = re.search(r"<<METADATA_YEAR:([^>]*)>>", text)
+        album_artist_match = re.search(r"<<METADATA_ALBUM_ARTIST:([^>]*)>>", text)
+        
+        # Use display path or filename as fallback for title
+        filename = os.path.splitext(os.path.basename(self.display_path if self.display_path else self.file_name))[0]
+        
+        # Add title metadata
+        if title_match:
+            metadata_options.extend(["-metadata", f"title=Dinginliğin Gücü"])
+        else:
+            metadata_options.extend(["-metadata", f"title={filename}"])
+            
+        # Add artist metadata
+        if artist_match:
+            metadata_options.extend(["-metadata", f"artist={artist_match.group(1)}"])
+        else:
+            metadata_options.extend(["-metadata", f"artist=Unknown"])
+            
+        # Add album metadata
+        if album_match:
+            metadata_options.extend(["-metadata", f"album={album_match.group(1)}"])
+        else:
+            metadata_options.extend(["-metadata", f"album={filename}"])
+            
+        # Add year metadata
+        if year_match:
+            metadata_options.extend(["-metadata", f"date={year_match.group(1)}"])
+        else:
+            # Use current year if year is not specified
+            import datetime
+            current_year = datetime.datetime.now().year
+            metadata_options.extend(["-metadata", f"date={current_year}"])
+
+        # Add album artist metadata
+        if album_artist_match:
+            metadata_options.extend(["-metadata", f"album_artist={album_artist_match.group(1)}"])
+        else:
+            metadata_options.extend(["-metadata", f"album_artist=Unknown"])
+            
+        # Add these to ffmpeg command
+        return metadata_options
 
     def _srt_time(self, t):
         """Helper function to format time for SRT files"""
@@ -702,11 +946,32 @@ class VoicePreviewThread(QThread):
         self.voice = voice
         self.speed = speed
         self.use_gpu = use_gpu
+        
+        # Cache location for preview audio
+        self.cache_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME, "preview_cache")
+        os.makedirs(self.cache_dir, exist_ok=True)
+        
+        # Calculate cache path
+        self.cache_path = self._get_cache_path()
+
+    def _get_cache_path(self):
+        """Generate a unique filename for the voice with its parameters"""
+        # For a voice formula, use a hash of the formula
+        if "*" in self.voice:
+            voice_id = f"voice_formula_{hashlib.md5(self.voice.encode()).hexdigest()[:8]}"
+        else:
+            voice_id = self.voice
+            
+        # Create a unique filename based on voice_id, language, and speed
+        filename = f"{voice_id}_{self.lang_code}_{self.speed:.2f}.wav"
+        return os.path.join(self.cache_dir, filename)
 
     def run(self):
         print(
             f"\nVoice: {self.voice}\nLanguage: {self.lang_code}\nSpeed: {self.speed}\nGPU: {self.use_gpu}\n"
         )
+        
+        # Generate the preview and save to cache
         try:
             device = "cuda" if self.use_gpu else "cpu"
             tts = self.kpipeline_class(
@@ -725,15 +990,9 @@ class VoicePreviewThread(QThread):
                 audio_segments.append(result.audio)
             if audio_segments:
                 audio = self.np_module.concatenate(audio_segments)
-                # Create temp wav file in a folder in the system temp directory
+                # Save directly to the cache path
-                temp_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME)
+                sf.write(self.cache_path, audio, 24000)
-                os.makedirs(temp_dir, exist_ok=True)
+                self.temp_wav = self.cache_path
-                fd, temp_path = tempfile.mkstemp(
-                    prefix="abogen_", suffix=".wav", dir=temp_dir
-                )
-                os.close(fd)
-                sf.write(temp_path, audio, 24000)
-                self.temp_wav = temp_path
             self.finished.emit()
         except Exception as e:
             self.error.emit(f"Voice preview error: {str(e)}")
@@ -746,6 +1005,7 @@ class PlayAudioThread(QThread):
     def __init__(self, wav_path, parent=None):
         super().__init__(parent)
         self.wav_path = wav_path
+        self.is_canceled = False
 
     def run(self):
         try:
@@ -755,10 +1015,37 @@ class PlayAudioThread(QThread):
             pygame.mixer.init()
             pygame.mixer.music.load(self.wav_path)
             pygame.mixer.music.play()
-            # Wait until playback is finished
+            # Wait until playback is finished or canceled
-            while pygame.mixer.music.get_busy():
+            while pygame.mixer.music.get_busy() and not self.is_canceled:
-                _time.sleep(0.1)
+                _time.sleep(0.2)
-            pygame.mixer.music.unload()
+                
+            # Make sure to clean up regardless of how we exited the loop
+            try:
+                pygame.mixer.music.stop()
+                pygame.mixer.music.unload()
+                pygame.mixer.quit()  # Quit the mixer
+            except Exception:
+                # Ignore any errors during cleanup
+                pass
+                
             self.finished.emit()
         except Exception as e:
-            self.error.emit(f"Audio playback error: {str(e)}")
+            # Handle initialization errors separately to give better error messages
+            if "mixer not initialized" in str(e):
+                self.error.emit("Audio playback error: The audio system was not properly initialized")
+            else:
+                self.error.emit(f"Audio playback error: {str(e)}")
+            
+    def stop(self):
+        """Safely stop playback"""
+        self.is_canceled = True
+        # Try to stop pygame if it's running, but catch all exceptions
+        try:
+            import pygame
+            if pygame.mixer.get_init():
+                if pygame.mixer.music.get_busy():
+                    pygame.mixer.music.stop()
+                pygame.mixer.music.unload()
+        except Exception:
+            # Ignore all errors when stopping since mixer might not be initialized
+            pass

abogen/gui.py

@@ -4,6 +4,8 @@ import tempfile
 import platform
 import base64
 import re
+import hf_tracker
+import hashlib  # Added for cache path generation
 from PyQt5.QtWidgets import (
     QApplication,
     QWidget,
@@ -23,6 +25,7 @@ from PyQt5.QtWidgets import (
     QCheckBox,
     QMenu,
     QAction,
+    QActionGroup,
 )
 from PyQt5.QtCore import (
     Qt,
@@ -71,7 +74,6 @@ from constants import (
 )
 from threading import Thread
 from voice_formula_gui import VoiceFormulaDialog
-from platformdirs import user_desktop_dir
 from voice_profiles import load_profiles
 
 # Import ctypes for Windows-specific taskbar icon
@@ -79,6 +81,13 @@ if platform.system() == "Windows":
     import ctypes
 
 
+class ShowWarningSignalEmitter(QObject):  # New class to handle signal emission
+    show_warning_signal = pyqtSignal(str, str)
+
+    def emit(self, title, message):
+        self.show_warning_signal.emit(title, message)
+
+
 class ThreadSafeLogSignal(QObject):
     log_signal = pyqtSignal(object)
 
@@ -95,9 +104,9 @@ class IconProvider(QFileIconProvider):
 
 
 class InputBox(QLabel):
-    LABEL_CSS = """QLabel { border:2px dashed #aaa; border-radius:5px; padding:20px; background:#f5f9fc; min-height:100px; } QLabel:hover { background:#e5f1fa; border-color:#6ab0de; }"""
+    LABEL_CSS = """QLabel { border:2px dashed #aaa; border-radius:5px; padding:20px; background:rgba(0, 102, 255, 0.05); min-height:100px; } QLabel:hover { background:rgba(0, 102, 255, 0.1); border-color:#6ab0de; }"""
-    LABEL_CSS_ACTIVE = """QLabel { border:2px dashed #42ad4a; border-radius:5px; padding:20px; background:#e6f7e6;min-height:100px; } QLabel:hover { background:#e5f1fa; border-color:#6ab0de; }"""
+    LABEL_CSS_ACTIVE = """QLabel { border:2px dashed #42ad4a; border-radius:5px; padding:20px; background:rgba(66, 173, 73, 0.1);min-height:100px; } QLabel:hover { background:rgba(66, 173, 73, 0.15); border-color:#42ad4a; }"""
-    LABEL_CSS_ERROR = """QLabel { border:2px dashed #e74c3c; border-radius:5px; padding:20px; background:#ffeaea; min-height:100px; color:#c0392b; } QLabel:hover { background:#ffeaea; border-color:#e74c3c; }"""
+    LABEL_CSS_ERROR = """QLabel { border:2px dashed #e74c3c; border-radius:5px; padding:20px; background:rgba(232, 78, 60, 0.10); min-height:100px; color:#c0392b; } QLabel:hover { background:rgba(232, 78, 60, 0.15); border-color:#e74c3c; }"""
 
     def __init__(self, parent=None):
         super().__init__(parent)
@@ -129,6 +138,13 @@ class InputBox(QLabel):
         self.edit_btn.clicked.connect(self.on_edit_clicked)
         self.edit_btn.hide()
 
+        # Add Go to folder button
+        self.go_to_folder_btn = QPushButton("Go to folder", self)
+        self.go_to_folder_btn.setStyleSheet("QPushButton { padding: 6px 10px; }")
+        self.go_to_folder_btn.setToolTip("Open the folder that contains the converted file")
+        self.go_to_folder_btn.clicked.connect(self.on_go_to_folder_clicked)
+        self.go_to_folder_btn.hide()
+
     def resizeEvent(self, event):
         super().resizeEvent(event)
         margin = 12
@@ -139,6 +155,11 @@ class InputBox(QLabel):
         # Position textbox button at top left
         self.textbox_btn.move(margin, margin)
         self.edit_btn.move(margin, margin)
+        # Position go to folder button at bottom right
+        self.go_to_folder_btn.move(
+            self.width() - self.go_to_folder_btn.width(),
+            self.height() - self.go_to_folder_btn.height() - margin,
+        )
 
     def set_file_info(self, file_path):
         # get icon without resizing using custom provider
@@ -228,6 +249,7 @@ class InputBox(QLabel):
             should_show_edit = True
 
         self.edit_btn.setVisible(should_show_edit)
+        self.go_to_folder_btn.show()
 
     def set_error(self, message):
         self.setText(message)
@@ -250,6 +272,7 @@ class InputBox(QLabel):
         # Show textbox and hide edit when input is cleared
         self.textbox_btn.show()
         self.edit_btn.hide()
+        self.go_to_folder_btn.hide()
 
     def _human_readable_size(self, size, decimal_places=2):
         for unit in ["B", "KB", "MB", "GB", "TB"]:
@@ -290,8 +313,8 @@ class InputBox(QLabel):
                 )
                 win.selected_book_path = file_path
                 win.open_book_file(
-                    file_path
+                    file_path  # This will handle the dialog and setting file info
-                )  # This will handle the dialog and setting file info
+                )
                 event.acceptProposedAction()
             else:
                 self.set_error("Please drop a .txt, .epub, or .pdf file.")
@@ -320,6 +343,17 @@ class InputBox(QLabel):
             # For regular txt files
             win.open_textbox_dialog()
 
+    def on_go_to_folder_clicked(self):
+        win = self.window()
+        # win.selected_file holds the path to the text that is converted.
+        file_to_check = win.selected_file
+        
+        if file_to_check and os.path.exists(file_to_check) and os.path.isfile(file_to_check):
+            folder_path = os.path.dirname(file_to_check)
+            QDesktopServices.openUrl(QUrl.fromLocalFile(folder_path))
+        else:
+            QMessageBox.warning(win, "Error", "Converted file not found.")
+
 
 class TextboxDialog(QDialog):
     def __init__(self, parent=None):
@@ -328,7 +362,7 @@ class TextboxDialog(QDialog):
         self.setWindowFlags(
             Qt.Window | Qt.WindowCloseButtonHint | Qt.WindowMaximizeButtonHint
         )
-        self.resize(600, 400)
+        self.resize(700, 500)
 
         layout = QVBoxLayout(self)
 
@@ -358,6 +392,11 @@ class TextboxDialog(QDialog):
         self.save_as_button.clicked.connect(self.save_as_text)
         self.save_as_button.setToolTip("Save the current text to a file")
 
+        self.insert_chapter_btn = QPushButton("Insert Chapter Marker", self)
+        self.insert_chapter_btn.setToolTip("Insert a chapter marker at the cursor")
+        self.insert_chapter_btn.clicked.connect(self.insert_chapter_marker)
+        button_layout.addWidget(self.insert_chapter_btn)
+
         self.cancel_button = QPushButton("Cancel", self)
         self.cancel_button.clicked.connect(self.reject)
 
@@ -382,8 +421,14 @@ class TextboxDialog(QDialog):
         return self.text_edit.toPlainText()
 
     def handle_ok(self):
+        text = self.text_edit.toPlainText()
+        # Check if text is empty based on character count
+        if calculate_text_length(text) == 0:
+            QMessageBox.warning(self, "Textbox Error", "Text cannot be empty.")
+            return
+
         # If the text hasn't changed, treat as cancel
-        if self.text_edit.toPlainText() == self.original_text:
+        if text == self.original_text:
             self.reject()
         else:
             # Check if we need to warn about overwriting a non-temporary file
@@ -444,6 +489,14 @@ class TextboxDialog(QDialog):
         except Exception as e:
             QMessageBox.critical(self, "Save Error", f"Could not save file:\n{e}")
 
+    def insert_chapter_marker(self):
+        # Insert a fixed chapter marker without prompting
+        cursor = self.text_edit.textCursor()
+        cursor.insertText("<<CHAPTER_MARKER:Title>>")
+        self.text_edit.setTextCursor(cursor)
+        self.update_char_count()
+        self.text_edit.setFocus()
+
 
 class abogen(QWidget):
     def __init__(self):
@@ -476,6 +529,7 @@ class abogen(QWidget):
             "max_subtitle_words", 50
         )  # Default max words per subtitle
         self.selected_format = self.config.get("selected_format", "wav")
+        self.separate_chapters_format = self.config.get("separate_chapters_format", "wav")  # Format for individual chapter files
         self.use_gpu = self.config.get(
             "use_gpu", True  # Load GPU setting with default True
         )
@@ -487,6 +541,11 @@ class abogen(QWidget):
         self.log_signal = ThreadSafeLogSignal()
         self.log_signal.log_signal.connect(self._update_log_main_thread)
 
+        # Create warning signal emitter
+        self.warning_signal_emitter = ShowWarningSignalEmitter()
+        self.warning_signal_emitter.show_warning_signal.connect(self.show_model_download_warning)
+        hf_tracker.set_show_warning_signal_emitter(self.warning_signal_emitter)
+
         # Set application icon
         icon_path = get_resource_path("abogen.assets", "icon.ico")
         if icon_path:
@@ -538,6 +597,9 @@ class abogen(QWidget):
         if self.check_updates:
             QTimer.singleShot(1000, self.check_for_updates_startup)
 
+        # Set hf_tracker callbacks
+        hf_tracker.set_log_callback(self.update_log)
+
     def initUI(self):
         self.setWindowTitle(f"{PROGRAM_NAME} v{VERSION}")
         screen = QApplication.primaryScreen().geometry()
@@ -634,6 +696,7 @@ class abogen(QWidget):
         self.btn_preview.clicked.connect(self.preview_voice)
         voice_row.addWidget(self.btn_preview)
         self.preview_playing = False
+        self.play_audio_thread = None  # Keep track of audio playing thread
         voice_layout.addLayout(voice_row)
         controls_layout.addLayout(voice_layout)
         # Subtitle mode
@@ -673,10 +736,23 @@ class abogen(QWidget):
         self.format_combo.setStyleSheet(
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
-        format_options = ["wav", "flac", "mp3"]
+        # Add items with display labels and underlying keys
-        self.format_combo.addItems(format_options)
+        for key, label in [
-        self.format_combo.setCurrentText(self.selected_format)
+            ("wav", "wav"),
-        self.format_combo.currentTextChanged.connect(self.on_format_changed)
+            ("flac", "flac"),
+            ("mp3", "mp3"),
+            ("opus", "opus (best compression)"),
+            ("m4b", "m4b (with chapters)"),
+        ]:
+            self.format_combo.addItem(label, key)
+        # Initialize selection by matching saved key
+        idx = self.format_combo.findData(self.selected_format)
+        if idx >= 0:
+            self.format_combo.setCurrentIndex(idx)
+        # Map selection back to key on change
+        self.format_combo.currentIndexChanged.connect(
+            lambda i: self.on_format_changed(self.format_combo.itemData(i))
+        )
         format_layout.addWidget(self.format_combo)
         controls_layout.addLayout(format_layout)
         # Save location
@@ -831,9 +907,7 @@ class abogen(QWidget):
         )
         dialog.setWindowModality(Qt.NonModal)
         dialog.setModal(False)
-        dialog.show()
+        dialog.show()            # We'll handle the dialog result asynchronously
-
-        # We'll handle the dialog result asynchronously
         def on_dialog_finished(result):
             if result != QDialog.Accepted:
                 return False
@@ -848,6 +922,7 @@ class abogen(QWidget):
             self.selected_chapters = all_checked_hrefs
             self.save_chapters_separately = dialog.get_save_chapters_separately()
             self.merge_chapters_at_end = dialog.get_merge_chapters_at_end()
+            self.save_as_project = dialog.get_save_as_project()
 
             # Store if the PDF has bookmarks for button text display
             if book_path.lower().endswith(".pdf"):
@@ -856,10 +931,54 @@ class abogen(QWidget):
             # Use "abogen" prefix for temporary files
             # Extract base name without extension
             base_name = os.path.splitext(os.path.basename(book_path))[0]
-            temp_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME)
+            
-            os.makedirs(temp_dir, exist_ok=True)
+            if self.save_as_project:
+                # Get project directory from user
+                project_dir = QFileDialog.getExistingDirectory(
+                    self, "Select Project Folder", "", QFileDialog.ShowDirsOnly
+                )
+                if not project_dir:
+                    # User cancelled, fallback to temp
+                    self.save_as_project = False
+                    temp_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME)
+                else:
+                    # Create project folder structure
+                    project_name = f"{base_name}_project"
+                    project_dir = os.path.join(project_dir, project_name)
+                    temp_dir = os.path.join(project_dir, "text")
+                    os.makedirs(temp_dir, exist_ok=True)
+                    
+                    # Save metadata if available
+                    meta_dir = os.path.join(project_dir, "metadata")
+                    os.makedirs(meta_dir, exist_ok=True) # Save book metadata if available
+                    if hasattr(dialog, "book_metadata"):
+                        meta_path = os.path.join(meta_dir, "book_info.txt")
+                        with open(meta_path, "w", encoding="utf-8") as f:
+                            # Clean HTML tags from metadata
+                            title = re.sub(r'<[^>]+>', '', str(dialog.book_metadata.get('title', 'Unknown')))
+                            publisher = re.sub(r'<[^>]+>', '', str(dialog.book_metadata.get('publisher', 'Unknown')))
+                            authors = [re.sub(r'<[^>]+>', '', str(author)) for author in dialog.book_metadata.get('authors', ['Unknown'])]
+                            publication_year = re.sub(r'<[^>]+>', '', str(dialog.book_metadata.get('publication_year', 'Unknown')))
+                            
+                            f.write(f"Title: {title}\n")
+                            f.write(f"Authors: {', '.join(authors)}\n")
+                            f.write(f"Publisher: {publisher}\n")
+                            f.write(f"Publication Year: {publication_year}\n")
+                            if dialog.book_metadata.get('description'):
+                                description = re.sub(r'<[^>]+>', '', str(dialog.book_metadata.get('description')))
+                                f.write(f"\nDescription:\n{description}\n")
+                        
+                        # Save cover image if available
+                    if dialog.book_metadata.get("cover_image"):
+                        cover_path = os.path.join(meta_dir, "cover.png")
+                        with open(cover_path, "wb") as f:
+                            f.write(dialog.book_metadata["cover_image"])
+            else:
+                temp_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME)
+                os.makedirs(temp_dir, exist_ok=True)
+                
             fd, tmp = tempfile.mkstemp(
-                prefix=f"abogen_{base_name}_", suffix=".txt", dir=temp_dir
+                prefix=f"{base_name}_", suffix=".txt", dir=temp_dir
             )
             os.close(fd)
             with open(tmp, "w", encoding="utf-8") as f:
@@ -1097,12 +1216,20 @@ class abogen(QWidget):
         QApplication.processEvents()
 
     def update_progress(self, value, etr_str):  # Add etr_str parameter
+        # Ensure progress doesn't exceed 99%
+        if value >= 100:
+            value = 99
         self.progress_bar.setValue(value)
         self.progress_bar.setFormat("%p%")  # Keep format as percentage only
         self.etr_label.setText(
             f"Estimated time remaining: {etr_str}"
         )  # Update ETR label
         self.etr_label.show()  # Show only when estimate is ready
+
+        # Disable cancel button if progress is >= 98%
+        if value >= 98:
+            self.btn_cancel.setEnabled(False)
+
         self.progress_bar.repaint()
         QApplication.processEvents()
 
@@ -1200,6 +1327,8 @@ class abogen(QWidget):
             self.conversion_thread.replace_single_newlines = (
                 self.replace_single_newlines
             )
+            # Pass separate_chapters_format setting
+            self.conversion_thread.separate_chapters_format = self.separate_chapters_format
             # Pass chapter count for EPUB or PDF files
             if self.selected_file_type in ["epub", "pdf"] and hasattr(
                 self, "selected_chapters"
@@ -1413,27 +1542,121 @@ class abogen(QWidget):
                 "Open File Error", f"Could not open file:\n{e}"
             )
 
+    def _get_preview_cache_path(self):
+        """Generate the expected cache path for the current voice settings."""
+        speed = self.speed_slider.value() / 100.0
+        voice_to_cache = ""
+        lang_to_cache = ""
+
+        if self.mixed_voice_state:
+            components = [f"{name}*{weight}" for name, weight in self.mixed_voice_state]
+            voice_formula = " + ".join(filter(None, components))
+            voice_to_cache = voice_formula
+            if self.selected_profile_name:
+                from voice_profiles import load_profiles
+                entry = load_profiles().get(self.selected_profile_name, {})
+                lang_to_cache = entry.get("language")
+            else:
+                lang_to_cache = self.selected_lang
+            if not lang_to_cache and self.mixed_voice_state:
+                lang_to_cache = (
+                    self.mixed_voice_state[0][0][0]
+                    if self.mixed_voice_state and self.mixed_voice_state[0][0]
+                    else None
+                )
+        elif self.selected_voice:
+            lang_to_cache = self.selected_voice[0]
+            voice_to_cache = self.selected_voice
+        else:  # No voice or profile selected
+            return None
+
+        if not lang_to_cache or not voice_to_cache:  # Not enough info
+            return None
+
+        cache_dir = os.path.join(tempfile.gettempdir(), PROGRAM_NAME, "preview_cache")
+        
+        if "*" in voice_to_cache:  # Voice formula
+            voice_id = f"voice_formula_{hashlib.md5(voice_to_cache.encode()).hexdigest()[:8]}"
+        else:  # Single voice
+            voice_id = voice_to_cache
+            
+        filename = f"{voice_id}_{lang_to_cache}_{speed:.2f}.wav"
+        return os.path.join(cache_dir, filename)
+
     def preview_voice(self):
         if self.preview_playing:
             try:
-                import pygame
+                if self.play_audio_thread and self.play_audio_thread.isRunning():
-
+                    # Call the stop method on PlayAudioThread to safely handle stopping
-                pygame.mixer.music.stop()
+                    self.play_audio_thread.stop()
-            except Exception:
+                    self.play_audio_thread.wait(500)  # Wait a bit
-                pass
+            except Exception as e:
+                print(f"Error stopping preview audio: {e}")
             self._preview_cleanup()
             return
 
         if hasattr(self, "preview_thread") and self.preview_thread.isRunning():
             return
 
+        # Check for cache first
+        cached_path = self._get_preview_cache_path()
+        if cached_path and os.path.exists(cached_path):
+            print(f"Cache hit for {cached_path}")
+            self.btn_preview.setEnabled(False)  # Disable button briefly
+            self.voice_combo.setEnabled(False)
+            self.btn_voice_formula_mixer.setEnabled(False)
+            self.btn_start.setEnabled(False)
+            
+            # Directly play from cache
+            self.preview_playing = True
+            self.btn_preview.setIcon(self.stop_icon)
+            self.btn_preview.setToolTip("Stop preview")
+            self.btn_preview.setEnabled(True)
+
+            def cleanup_cached_play():
+                self._preview_cleanup()
+
+            try:
+                # Ensure pygame mixer is initialized for the audio thread
+                import pygame
+                if not pygame.mixer.get_init():
+                    pygame.mixer.init()
+
+                self.play_audio_thread = PlayAudioThread(cached_path)
+                self.play_audio_thread.finished.connect(cleanup_cached_play)
+                self.play_audio_thread.error.connect(
+                    lambda msg: (self._show_preview_error_box(msg), cleanup_cached_play())
+                )
+                self.play_audio_thread.start()
+            except Exception as e:
+                self._show_error_message_box(
+                    "Preview Error", f"Could not play cached preview audio:\n{e}"
+                )
+                cleanup_cached_play()
+            return
+
+        # If no cache hit, proceed to load pipeline and generate
         self.btn_preview.setEnabled(False)
         self.btn_preview.setToolTip("Loading...")
         self.voice_combo.setEnabled(False)
         self.btn_voice_formula_mixer.setEnabled(False)  # Disable mixer button
         self.btn_start.setEnabled(False)  # Disable start button during preview
-        # start loading animation
+
-        self.loading_movie.start()
+        # Start loading animation - ensure signal connection is always active
+        if hasattr(self, "loading_movie"):
+            # Disconnect previous connections to avoid multiple connections
+            try:
+                self.loading_movie.frameChanged.disconnect()
+            except TypeError:
+                pass  # Ignore error if not connected
+
+            # Reconnect the signal
+            self.loading_movie.frameChanged.connect(
+                lambda: self.btn_preview.setIcon(
+                    QIcon(self.loading_movie.currentPixmap())
+                )
+            )
+            self.loading_movie.start()
 
         def pipeline_loaded_callback(np_module, kpipeline_class, error):
             self._on_pipeline_loaded_for_preview(np_module, kpipeline_class, error)
@@ -1462,14 +1685,14 @@ class abogen(QWidget):
             # Build voice formula string
             components = [f"{name}*{weight}" for name, weight in self.mixed_voice_state]
             voice = " + ".join(filter(None, components))
-            # determine language: use profile setting if available, else first voice code
+            # determine language: use profile setting, else explicit mixer selection, else fallback to first voice code
             if self.selected_profile_name:
                 from voice_profiles import load_profiles
 
                 entry = load_profiles().get(self.selected_profile_name, {})
                 lang = entry.get("language")
             else:
-                lang = None
+                lang = self.selected_lang
             if not lang and self.mixed_voice_state:
                 lang = (
                     self.mixed_voice_state[0][0][0]
@@ -1484,48 +1707,66 @@ class abogen(QWidget):
         gpu_msg, gpu_ok = get_gpu_acceleration(self.use_gpu)
 
         self.preview_thread = VoicePreviewThread(
-            np_module, kpipeline_class, lang, voice, speed, gpu_ok 
+            np_module, kpipeline_class, lang, voice, speed, gpu_ok
         )
         self.preview_thread.finished.connect(self._play_preview_audio)
         self.preview_thread.error.connect(self._preview_error)
         self.preview_thread.start()
 
-    def _play_preview_audio(self):
+    def _play_preview_audio(self, from_cache=True):  # from_cache default is now False
-        temp_wav = self.preview_thread.temp_wav
+        # If preview_thread is the source, get temp_wav from it
-        if not temp_wav:
+        if hasattr(self, 'preview_thread') and not from_cache:
-            self.loading_movie.stop()
+            temp_wav = self.preview_thread.temp_wav
+        elif from_cache:  # This case is now handled before calling _play_preview_audio
+            cached_path = self._get_preview_cache_path()
+            if cached_path and os.path.exists(cached_path):
+                temp_wav = cached_path
+            else:  # Should not happen if cache check was done
+                self._show_error_message_box("Preview Error", "Cache file expected but not found.")
+                self._preview_cleanup()
+                return
+        else:  # Should have temp_wav from preview_thread or handled by cache check
+            self._show_error_message_box("Preview Error", "Preview audio path not found.")
+            self._preview_cleanup()
+            return
 
+        if not temp_wav:
+            if hasattr(self, 'loading_movie'): self.loading_movie.stop()
             self._show_error_message_box(
                 "Preview Error", "Preview error: No audio generated."
             )
-            self.btn_preview.setIcon(self.play_icon)
+            self._preview_cleanup()
-            self.btn_preview.setToolTip("Preview selected voice")
-            self.btn_preview.setEnabled(True)
-            self.voice_combo.setEnabled(True)
-            self.btn_voice_formula_mixer.setEnabled(True)  # Re-enable mixer button
-            self.btn_start.setEnabled(True)
             return
+            
         # stop loading animation, switch to stop icon
-        self.loading_movie.stop()
+        if hasattr(self, 'loading_movie'): self.loading_movie.stop()
         self.preview_playing = True
         self.btn_preview.setIcon(self.stop_icon)
         self.btn_preview.setToolTip("Stop preview")
         self.btn_preview.setEnabled(True)
 
         def cleanup():
-            try:
+            # Only remove if not from cache AND it's a temp file from VoicePreviewThread
-                os.remove(temp_wav)
+            if not from_cache and hasattr(self, 'preview_thread') and hasattr(self.preview_thread, 'temp_wav') and self.preview_thread.temp_wav == temp_wav:
-            except Exception:
+                try:
-                pass
+                    if os.path.exists(temp_wav):  # Ensure it exists before trying to remove
+                        os.remove(temp_wav)
+                except Exception:
+                    pass
             self._preview_cleanup()
 
         try:
-            self.audio_thread = PlayAudioThread(temp_wav)
+            # Ensure pygame mixer is initialized for the audio thread
-            self.audio_thread.finished.connect(cleanup)
+            import pygame
-            self.audio_thread.error.connect(
+            if not pygame.mixer.get_init():
+                pygame.mixer.init()
+
+            self.play_audio_thread = PlayAudioThread(temp_wav)
+            self.play_audio_thread.finished.connect(cleanup)
+            self.play_audio_thread.error.connect(
                 lambda msg: (self._show_preview_error_box(msg), cleanup())
             )
-            self.audio_thread.start()
+            self.play_audio_thread.start()
         except Exception as e:
             self._show_error_message_box(
                 "Preview Error", f"Could not play preview audio:\n{e}"
@@ -1548,12 +1789,12 @@ class abogen(QWidget):
 
     def _preview_cleanup(self):
         self.preview_playing = False
-        self.loading_movie.stop()
+        if hasattr(self, 'loading_movie'): self.loading_movie.stop()
         try:
-            self.loading_movie.frameChanged.disconnect()
+            if hasattr(self, 'loading_movie'): self.loading_movie.frameChanged.disconnect()
         except Exception:
             pass  # Ignore error if not connected
-        self.btn_preview.setIcon(self.play_icon) 
+        self.btn_preview.setIcon(self.play_icon)
         self.btn_preview.setToolTip("Preview selected voice")
         self.btn_preview.setEnabled(True)
         self.voice_combo.setEnabled(True)
@@ -1683,13 +1924,32 @@ class abogen(QWidget):
         max_words_action = QAction("Configure max words per subtitle", self)
         max_words_action.triggered.connect(self.set_max_subtitle_words)
         menu.addAction(max_words_action)
+        
+        # Add separate chapters format option
+        separate_chapters_format_menu = QMenu("Separate chapters audio format", self)
+        separate_chapters_format_menu.setToolTip("Choose the format for individual chapter files")
+        
+        format_group = QActionGroup(self)
+        format_group.setExclusive(True)
+        
+        for format_option in ["wav", "mp3", "flac", "opus"]:
+            format_action = QAction(format_option, self)
+            format_action.setCheckable(True)
+            format_action.setChecked(self.separate_chapters_format == format_option)
+            format_action.triggered.connect(lambda checked, fmt=format_option: self.set_separate_chapters_format(fmt))
+            format_group.addAction(format_action)
+            separate_chapters_format_menu.addAction(format_action)
+            
+        menu.addMenu(separate_chapters_format_menu)
 
-        # Add seperator
+        # Add separator
         menu.addSeparator()
 
-        # Add shortcut to desktop (Windows only)
+        # Add shortcut to desktop (Windows or Linux)
-        if platform.system() == "Windows":
+        if platform.system() == "Windows" or platform.system() == "Linux":
-            add_shortcut_action = QAction("Create desktop shortcut", self)
+            # Use extended label on Linux
+            label = "Create desktop shortcut and install" if platform.system() == "Linux" else "Create desktop shortcut"
+            add_shortcut_action = QAction(label, self)
             add_shortcut_action.triggered.connect(self.add_shortcut_to_desktop)
             menu.addAction(add_shortcut_action)
 
@@ -1704,7 +1964,7 @@ class abogen(QWidget):
         menu.addAction(open_temp_action)
 
         # Add clear temporary files option
-        clear_temp_action = QAction("Clear all temporary files", self)
+        clear_temp_action = QAction("Clear temporary files", self)
         clear_temp_action.triggered.connect(self.clear_temp_files)
         menu.addAction(clear_temp_action)
 
@@ -1762,62 +2022,133 @@ class abogen(QWidget):
 
     def add_shortcut_to_desktop(self):
         """Create a desktop shortcut to this program using PowerShell."""
-        import sys, subprocess
+        import sys
-        from PyQt5.QtWidgets import QMessageBox
+        from platformdirs import user_desktop_dir
+        from utils import create_process
 
         try:
-            # where to put the .lnk
+            if platform.system() == "Windows":
-            desktop = user_desktop_dir()
+                # where to put the .lnk
-            shortcut_path = os.path.join(desktop, "abogen.lnk")
+                desktop = user_desktop_dir()
+                shortcut_path = os.path.join(desktop, "abogen.lnk")
 
-            # target exe
+                # target exe
-            python_dir = os.path.dirname(sys.executable)
+                python_dir = os.path.dirname(sys.executable)
-            target = os.path.join(python_dir, "Scripts", "abogen.exe")
+                target = os.path.join(python_dir, "Scripts", "abogen.exe")
-            if not os.path.exists(target):
+                if not os.path.exists(target):
-                QMessageBox.critical(
+                    QMessageBox.critical(
-                    self, "Shortcut Error", f"Could not find abogen.exe at:\n{target}"
+                        self, "Shortcut Error", f"Could not find abogen.exe at:\n{target}"
+                    )
+                    return
+
+                # icon (fallback to exe if missing)
+                icon = get_resource_path("abogen.assets", "icon.ico")
+                if not icon or not os.path.exists(icon):
+                    icon = target            # Create a more direct PowerShell command
+                shortcut_ps = shortcut_path.replace("'", "''").replace("\\", "\\\\")
+                target_ps = target.replace("'", "''").replace("\\", "\\\\")
+                workdir_ps = os.path.dirname(target).replace("'", "''").replace("\\", "\\\\")
+                icon_ps = icon.replace("'", "''").replace("\\", "\\\\")
+                  # Create PowerShell script as a single line with no line breaks (more reliable)
+                ps_cmd = f"$s=New-Object -ComObject WScript.Shell; $lnk=$s.CreateShortcut('{shortcut_ps}'); $lnk.TargetPath='{target_ps}'; $lnk.WorkingDirectory='{workdir_ps}'; $lnk.IconLocation='{icon_ps}'; $lnk.Save()"
+            
+                # Run PowerShell with the command directly
+                proc = create_process("powershell -NoProfile -ExecutionPolicy Bypass -Command \"" + ps_cmd + "\"")
+                proc.wait()
+            
+                if proc.returncode == 0:
+                    QMessageBox.information(
+                        self,
+                        "Shortcut Created",
+                        f"Shortcut created on desktop:\n{shortcut_path}",
+                    )
+                else:
+                    QMessageBox.critical(
+                        self,
+                        "Shortcut Error",
+                        f"PowerShell failed with exit code: {proc.returncode}"
+                    )
+            elif platform.system() == "Linux":
+                desktop = user_desktop_dir()
+                if not desktop or not os.path.isdir(desktop):
+                    QMessageBox.critical(self, "Shortcut Error", "Could not determine desktop directory.")
+                    return
+
+                shortcut_path = os.path.join(desktop, "abogen.desktop")
+
+                import shutil
+                found = shutil.which("abogen")
+                if found:
+                    target = found
+                else:
+                    local_bin = os.path.expanduser("~/.local/bin/abogen")
+                    if os.path.exists(local_bin):
+                        target = local_bin
+                    else:
+                        python_dir = os.path.dirname(sys.executable)
+                        target = os.path.join(python_dir, "bin", "abogen")
+                        if not os.path.exists(target):
+                            target_fallback = os.path.join(python_dir, "abogen")
+                            if os.path.exists(target_fallback):
+                                target = target_fallback
+                            else:
+                                QMessageBox.critical(self, "Shortcut Error", "Could not find abogen executable in PATH or common installation directories.")
+                                return
+
+                icon_path = get_resource_path("abogen.assets", "icon.png")
+
+                desktop_entry_content = f"""[Desktop Entry]
+Version={VERSION}
+Name={PROGRAM_NAME}
+Comment={PROGRAM_DESCRIPTION}
+Exec={target}
+Icon={icon_path}
+Terminal=false
+Type=Application
+Categories=AudioVideo;Audio;Utility;
+"""
+                with open(shortcut_path, "w", encoding="utf-8") as f:
+                    f.write(desktop_entry_content)
+
+                os.chmod(shortcut_path, 0o755)
+
+                QMessageBox.information(
+                    self,
+                    "Shortcut Created",
+                    f"Shortcut created on desktop:\n{shortcut_path}",
                 )
-                return
 
-            # icon (fallback to exe if missing)
+                # Offer installation for current user under ~/.local/share/applications
-            icon = get_resource_path("abogen.assets", "icon.ico")
+                reply = QMessageBox.question(
-            if not icon or not os.path.exists(icon):
+                    self,
-                icon = target
+                    "Install Application Entry",
+                    "Install application entry for current user?",
+                    QMessageBox.Yes | QMessageBox.No,
+                )
+                if reply == QMessageBox.Yes:
+                    import shutil
+                    user_app_dir = os.path.expanduser("~/.local/share/applications")
+                    os.makedirs(user_app_dir, exist_ok=True)
+                    user_entry = os.path.join(user_app_dir, "abogen.desktop")
+                    try:
+                        shutil.copyfile(shortcut_path, user_entry)
+                        os.chmod(user_entry, 0o644)
+                        QMessageBox.information(
+                            self,
+                            "Installation Complete",
+                            f"Desktop entry installed to {user_entry}",
+                        )
+                    except Exception as e:
+                        QMessageBox.warning(
+                            self,
+                            "Install Error",
+                            f"Could not install entry:\n{e}",
+                        )
+            else:
+                QMessageBox.information(
+                    self, "Unsupported OS", "Desktop shortcut creation is not supported on this operating system."
+                )
 
-            # PowerShell command to make the shortcut
-            ps_cmd = r"""
-                    $s = New-Object -ComObject WScript.Shell
-                    $lnk = $s.CreateShortcut('{lnk}')
-                    $lnk.TargetPath = '{tgt}'
-                    $lnk.WorkingDirectory = '{cwd}'
-                    $lnk.IconLocation = '{ico}'
-                    $lnk.Save()
-                    """.format(
-                lnk=shortcut_path.replace("'", "''"),
-                tgt=target.replace("'", "''"),
-                cwd=os.path.dirname(target).replace("'", "''"),
-                ico=icon.replace("'", "''"),
-            ).strip()
-
-            subprocess.run(
-                ["powershell", "-NoProfile", "-Command", ps_cmd],
-                check=True,
-                stdout=subprocess.PIPE,
-                stderr=subprocess.PIPE,
-            )
-
-            QMessageBox.information(
-                self,
-                "Shortcut Created",
-                f"Shortcut created on desktop:\n{shortcut_path}",
-            )
-
-        except subprocess.CalledProcessError as e:
-            QMessageBox.critical(
-                self,
-                "Shortcut Error",
-                f"PowerShell failed:\n{e.stderr.decode(errors='ignore')}",
-            )
         except Exception as e:
             QMessageBox.critical(
                 self, "Shortcut Error", f"Could not create shortcut:\n{e}"
@@ -1829,6 +2160,7 @@ class abogen(QWidget):
 
     def show_voice_formula_dialog(self):
         from voice_profiles import load_profiles
+
         profiles = load_profiles()
         initial_state = None
         selected_profile = self.selected_profile_name
@@ -2010,7 +2342,7 @@ class abogen(QWidget):
             pass
 
     def clear_temp_files(self):
-        """Clear all temporary files created by the program."""
+        """Clear temporary files created by the program."""
         import glob
 
         try:
@@ -2024,25 +2356,49 @@ class abogen(QWidget):
             # Count the files
             file_count = len(temp_files)
 
-            if file_count == 0:
+            # Check for preview cache files
+            preview_cache_dir = os.path.join(temp_dir, "preview_cache")
+            preview_files = []
+            if os.path.exists(preview_cache_dir):
+                preview_pattern = os.path.join(preview_cache_dir, "*.wav")
+                preview_files = glob.glob(preview_pattern)
+            
+            preview_count = len(preview_files)
+            
+            if file_count == 0 and preview_count == 0:
                 QMessageBox.information(
                     self, "No Temporary Files", "No temporary files were found."
                 )
                 return
 
-            # Confirm with the user
+            # Create a custom message box with checkbox
-            confirm = QMessageBox.question(
+            msg_box = QMessageBox(self)
-                self,
+            msg_box.setIcon(QMessageBox.Question)
-                "Clear Temporary Files",
+            msg_box.setWindowTitle("Clear Temporary Files")
-                f"Found {file_count} temporary file{'s' if file_count != 1 else ''} in the {PROGRAM_NAME} temp folder.\n"
+            
-                "Do you want to delete them?",
+            msg_text = f"Found {file_count} temporary file{'s' if file_count != 1 else ''} in the {PROGRAM_NAME} temp folder."
-                QMessageBox.Yes | QMessageBox.No,
+            if preview_count > 0:
-            )
+                msg_text += f"\nAlso found {preview_count} preview cache file{'s' if preview_count != 1 else ''}."
-
+                
-            if confirm != QMessageBox.Yes:
+            msg_box.setText(msg_text + "\nDo you want to delete them?")
+            
+            # Add checkbox for preview cache
+            preview_cache_checkbox = QCheckBox("Clean preview cache", msg_box)
+            preview_cache_checkbox.setChecked(False)
+            # Only enable checkbox if preview files exist
+            preview_cache_checkbox.setEnabled(preview_count > 0)
+            
+            # Add the checkbox to the layout
+            msg_box.setCheckBox(preview_cache_checkbox)
+            
+            # Add buttons
+            msg_box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+            msg_box.setDefaultButton(QMessageBox.Yes)
+            
+            if msg_box.exec_() != QMessageBox.Yes:
                 return
 
-            # Delete the files
+            # Delete the text files
             deleted_count = 0
             for file_path in temp_files:
                 try:
@@ -2050,12 +2406,25 @@ class abogen(QWidget):
                     deleted_count += 1
                 except Exception as e:
                     print(f"Error deleting {file_path}: {e}")
+            
+            # Delete preview cache files if checkbox is checked
+            deleted_preview_count = 0
+            if preview_cache_checkbox.isChecked() and preview_count > 0:
+                for file_path in preview_files:
+                    try:
+                        os.remove(file_path)
+                        deleted_preview_count += 1
+                    except Exception as e:
+                        print(f"Error deleting preview cache {file_path}: {e}")
 
+            # Build result message
+            result_msg = f"Successfully deleted {deleted_count} temporary file{'s' if deleted_count != 1 else ''}."
+            if preview_cache_checkbox.isChecked() and deleted_preview_count > 0:
+                result_msg += f"\nAlso deleted {deleted_preview_count} preview cache file{'s' if deleted_preview_count != 1 else ''}."
+                
             # Show results
             QMessageBox.information(
-                self,
+                self, "Temporary Files Cleared", result_msg
-                "Temporary Files Cleared",
-                f"Successfully deleted {deleted_count} temporary file{'s' if deleted_count != 1 else ''}.",
             )
 
             # If currently selected file is in the temp directory, clear the UI
@@ -2099,3 +2468,13 @@ class abogen(QWidget):
                 "Setting Saved",
                 f"Maximum words per subtitle set to {value}.",
             )
+
+    def set_separate_chapters_format(self, fmt):
+        """Set the format for separate chapters audio files."""
+        self.separate_chapters_format = fmt
+        self.config["separate_chapters_format"] = fmt
+        save_config(self.config)
+
+    def show_model_download_warning(self, title, message):
+        QMessageBox.information(self, title, message)
+

abogen/hf_tracker.py

@@ -0,0 +1,36 @@
+log_callback = None
+show_warning_signal_emitter = None  # Renamed for clarity
+
+def set_log_callback(cb):
+    global log_callback
+    log_callback = cb
+
+def set_show_warning_signal_emitter(emitter):  # Renamed for clarity
+    global show_warning_signal_emitter
+    show_warning_signal_emitter = emitter
+
+from huggingface_hub import hf_hub_download
+
+def tracked_hf_hub_download(*args, **kwargs):
+    try:
+        local_kwargs = dict(kwargs)
+        local_kwargs["local_files_only"] = True
+        hf_hub_download(*args, **local_kwargs)
+    except Exception:
+        repo_id = kwargs.get("repo_id", "<unknown repo>")
+        filename = kwargs.get("filename", "<unknown file>")
+        if filename.endswith(".pth"):
+            msg = f"\nDownloading model '{filename}' from Hugging Face ({repo_id}). This may take a while. Please wait..."
+            if show_warning_signal_emitter:  # Check if the emitter is set
+                show_warning_signal_emitter.emit("Downloading Model", f"Downloading model '{filename}' from Hugging Face repository '{repo_id}'. This may take a while, please wait.")
+        else:
+            msg = f"\nDownloading '{filename}' from Hugging Face ({repo_id}). Please wait..."
+        if log_callback:
+            print(msg, flush=True)
+            log_callback(msg)
+        else:
+            print(msg, flush=True)
+    return hf_hub_download(*args, **kwargs)
+
+import huggingface_hub
+huggingface_hub.hf_hub_download = tracked_hf_hub_download

abogen/is_nvidia.py

@@ -0,0 +1,16 @@
+import gpustat
+
+def check():
+    try:
+        stats = gpustat.new_query()
+    except Exception:
+        return False
+
+    for gpu in stats.gpus:
+        print(gpu.name)
+        if 'nvidia' in gpu.name.lower():
+            return True
+    return False
+
+if __name__ == "__main__":
+    print(check())

abogen/main.py

@@ -10,6 +10,10 @@ from gui import abogen
 from utils import get_resource_path
 from constants import PROGRAM_NAME, VERSION
 
+# Set environment variables for AMD ROCm
+os.environ["MIOPEN_FIND_MODE"] = "FAST"
+os.environ["MIOPEN_CONV_PRECISE_ROCM_TUNING"] = "0"
+
 # Ensure sys.stdout and sys.stderr are valid in GUI mode
 if sys.stdout is None:
     sys.stdout = open(os.devnull, "w")
@@ -48,6 +52,13 @@ def main():
     if icon_path:
         app.setWindowIcon(QIcon(icon_path))
 
+    # Set the .desktop name on Linux
+    if platform.system() == "Linux":
+        try:
+            app.setDesktopFileName("abogen.desktop")
+        except AttributeError:
+            pass
+
     ex = abogen()
     ex.show()
     sys.exit(app.exec_())

abogen/utils.py

@@ -1,4 +1,5 @@
 import os
+import sys
 import json
 import warnings
 import platform
@@ -66,10 +67,20 @@ def get_version():
 
 # Define config path
 def get_user_config_path():
-    if os.name == "nt":
+    from platformdirs import user_config_dir
-        config_dir = os.path.join(os.environ["APPDATA"], "abogen")
+
+    # TODO Config directory is changed for Linux and MacOS. But if old config exists, it will be used.
+    # On non‑Windows, prefer ~/.config/abogen if it already exists
+    if platform.system() != "Windows":
+        custom_dir = os.path.join(os.path.expanduser("~"), ".config", "abogen")
+        if os.path.exists(custom_dir):
+            config_dir = custom_dir
+        else:
+            config_dir = user_config_dir("abogen", appauthor=False, roaming=True)
     else:
-        config_dir = os.path.join(os.path.expanduser("~"), ".config", "abogen")
+        # Windows and fallback case
+        config_dir = user_config_dir("abogen", appauthor=False, roaming=True)
+
     os.makedirs(config_dir, exist_ok=True)
     return os.path.join(config_dir, "config.json")
 
@@ -92,6 +103,89 @@ def clean_text(text, *args, **kwargs):
     return text
 
 
+default_encoding = sys.getfilesystemencoding()
+
+def create_process(cmd, stdin=None, text=True, capture_output=False):
+    import logging
+    logger = logging.getLogger(__name__)
+    
+    # Configure root logger to output to console if not already configured
+    root = logging.getLogger()
+    if not root.handlers:
+        handler = logging.StreamHandler(sys.stdout)
+        formatter = logging.Formatter('%(message)s')
+        handler.setFormatter(formatter)
+        root.addHandler(handler)
+        root.setLevel(logging.INFO)
+    
+    # Determine shell usage: use shell only for string commands
+    use_shell = isinstance(cmd, str)
+    kwargs = {
+        "shell": use_shell,
+        "stdout": subprocess.PIPE,
+        "stderr": subprocess.STDOUT,
+        "bufsize": 1,  # Line buffered
+    }
+
+    if text:
+        # Configure for text I/O
+        kwargs["text"] = True
+        kwargs["encoding"] = default_encoding
+        kwargs["errors"] = "replace"
+    else:
+        # Configure for binary I/O
+        kwargs["text"] = False
+        # For binary mode, 'encoding' and 'errors' arguments must not be passed to Popen
+        kwargs["bufsize"] = 0  # Use unbuffered mode for binary data
+
+    if stdin is not None:
+        kwargs["stdin"] = stdin
+
+    if platform.system() == "Windows":
+        startupinfo = subprocess.STARTUPINFO()
+        startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
+        startupinfo.wShowWindow = subprocess.SW_HIDE
+        kwargs.update(
+            {"startupinfo": startupinfo, "creationflags": subprocess.CREATE_NO_WINDOW}
+        )
+
+    # Print the command being executed
+    print(f"Executing: {cmd if isinstance(cmd, str) else ' '.join(cmd)}")
+    
+    proc = subprocess.Popen(cmd, **kwargs)
+    
+    # Stream output to console in real-time if not capturing
+    if proc.stdout and not capture_output:
+        def _stream_output(stream):
+            if text:
+                # For text mode, read character by character for real-time output
+                while True:
+                    char = stream.read(1)
+                    if not char:
+                        break
+                    # Direct write to stdout for immediate feedback
+                    sys.stdout.write(char)
+                    sys.stdout.flush()
+            else:
+                # For binary mode, read small chunks
+                while True:
+                    chunk = stream.read(1)  # Read byte by byte for real-time output
+                    if not chunk:
+                        break
+                    try:
+                        # Try to decode binary data for display
+                        sys.stdout.write(chunk.decode(default_encoding, errors='replace'))
+                        sys.stdout.flush()
+                    except Exception:
+                        pass
+            stream.close()
+        
+        # Start a daemon thread to handle output streaming
+        Thread(target=_stream_output, args=(proc.stdout,), daemon=True).start()
+
+    return proc
+
+
 def load_config():
     try:
         with open(get_user_config_path(), "r", encoding="utf-8") as f:
@@ -109,10 +203,16 @@ def save_config(config):
 
 
 def calculate_text_length(text):
-    # Remove double newlines (replace them with single newlines)
+    # Ignore chapter markers
-    cleaned_text = text.replace("\n\n", "")
+    text = re.sub(r"<<CHAPTER_MARKER:.*?>>", "", text)
+    # Ignore metadata patterns
+    text = re.sub(r"<<METADATA_[^:]+:[^>]*>>", "", text)
+    # Ignore newlines
+    text = text.replace("\n", "")
+    # Ignore leading/trailing spaces
+    text = text.strip()
     # Calculate character count
-    char_count = len(cleaned_text)
+    char_count = len(text)
     return char_count
 
 
@@ -131,35 +231,26 @@ def prevent_sleep_start():
     system = platform.system()
     if system == "Windows":
         import ctypes
-
         ctypes.windll.kernel32.SetThreadExecutionState(
             0x80000000 | 0x00000001 | 0x00000040
-        )  # ES_CONTINUOUS | ES_SYSTEM_REQUIRED | ES_AWAYMODE_REQUIRED
+        )
     elif system == "Darwin":
-        _sleep_procs["Darwin"] = subprocess.Popen(["caffeinate"])
+        _sleep_procs["Darwin"] = create_process(["caffeinate"])
     elif system == "Linux":
-        try:
+        # use a sleep that never exits so inhibition stays active
-            _sleep_procs["Linux"] = subprocess.Popen(
+        _sleep_procs["Linux"] = create_process([
-                [
+            "systemd-inhibit",
-                    "systemd-inhibit",
+            "--what=handle-lid-switch:sleep",
-                    "--what=sleep",
+            "--mode=block",
-                    "--why=TextToAudiobook conversion",
+            "sleep",
-                    "sleep",
+            "infinity",
-                    "999999",
+        ])
-                ]
-            )
-        except Exception:
-            try:
-                subprocess.Popen(["xdg-screensaver", "reset"])
-            except Exception:
-                pass
 
 
 def prevent_sleep_end():
     system = platform.system()
     if system == "Windows":
         import ctypes
-
         ctypes.windll.kernel32.SetThreadExecutionState(0x80000000)  # ES_CONTINUOUS
     elif system in ("Darwin", "Linux") and _sleep_procs[system]:
         try:

abogen/voice_formula_gui.py

@@ -47,7 +47,7 @@ VOICE_MIXER_WIDTH = 100
 SLIDER_WIDTH = 32
 MIN_WINDOW_WIDTH = 600
 MIN_WINDOW_HEIGHT = 400
-INITIAL_WINDOW_WIDTH = 1000
+INITIAL_WINDOW_WIDTH = 1200
 INITIAL_WINDOW_HEIGHT = 500
 
 # Language options for the language selector loaded from constants
@@ -264,14 +264,12 @@ class HoverLabel(QLabel):
         self.voice_name = voice_name
         self.setMouseTracking(True)
         self.setStyleSheet(
-            "background-color: #e0e0e0; border-radius: 4px; padding: 3px 6px 3px 6px; margin: 2px;"
+            "background-color: rgba(140, 140, 140, 0.15); border-radius: 4px; padding: 3px 6px 3px 6px; margin: 2px;"
         )
 
         # Create delete button
         self.delete_button = QPushButton("×", self)
         self.delete_button.setFixedSize(16, 16)
-        self.delete_button = QPushButton("×", self)
-        self.delete_button.setFixedSize(16, 16)
         self.delete_button.setStyleSheet(
             """
             QPushButton {
@@ -310,6 +308,12 @@ class HoverLabel(QLabel):
 class VoiceFormulaDialog(QDialog):
     def __init__(self, parent=None, initial_state=None, selected_profile=None):
         super().__init__(parent)
+        # Store original profile/mix state for restoration on cancel
+        self._original_profile_name = None
+        self._original_mixed_voice_state = None
+        if parent is not None:
+            self._original_profile_name = getattr(parent, "selected_profile_name", None)
+            self._original_mixed_voice_state = getattr(parent, "mixed_voice_state", None)
         profiles = load_profiles()
         self._virtual_new_profile = False
         if not profiles:
@@ -413,6 +417,11 @@ class VoiceFormulaDialog(QDialog):
             self.language_combo.setCurrentIndex(idx)
         self.language_combo.currentIndexChanged.connect(self.mark_profile_modified)
         header_row.addWidget(self.language_combo)
+        # Preview current voice mix using main window's preview
+        self.btn_preview_mix = QPushButton("Preview", self)
+        self.btn_preview_mix.setToolTip("Preview current voice mix")
+        self.btn_preview_mix.clicked.connect(self.preview_current_mix)
+        header_row.addWidget(self.btn_preview_mix)
         mixer_layout.addLayout(header_row)
 
         # Error message
@@ -708,6 +717,9 @@ class VoiceFormulaDialog(QDialog):
         ]
 
         total = sum(w for _, w in selected)
+        # disable Preview if no voices selected, but don't enable while loading
+        if not getattr(self, "_loading", False):
+            self.btn_preview_mix.setEnabled(total > 0)
 
         if total > 0:
             self.error_label.hide()
@@ -726,7 +738,7 @@ class VoiceFormulaDialog(QDialog):
                 percentage = weight / total * 100
                 # Make the voice name bold and include percentage
                 voice_label = HoverLabel(
-                    f'<b><span style="color:#1976d2">{name}: {percentage:.1f}%</span></b>',
+                    f'<b><span style="color:#007dff">{name}: {percentage:.1f}%</span></b>',
                     name,
                 )
                 voice_label.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
@@ -908,6 +920,13 @@ class VoiceFormulaDialog(QDialog):
         super().accept()
 
     def reject(self):
+        # Restore parent's profile/mix state on cancel
+        parent = self.parent()
+        if parent is not None:
+            if hasattr(self, "_original_profile_name"):
+                parent.selected_profile_name = self._original_profile_name
+            if hasattr(self, "_original_mixed_voice_state"):
+                parent.mixed_voice_state = self._original_mixed_voice_state
         # Prompt to save if unsaved changes, then check for zero-weight error after save
         if self._has_unsaved_changes():
             if not self._prompt_save_changes():
@@ -917,6 +936,13 @@ class VoiceFormulaDialog(QDialog):
         super().reject()
 
     def closeEvent(self, event):
+        # Restore parent's profile/mix state on close
+        parent = self.parent()
+        if parent is not None:
+            if hasattr(self, "_original_profile_name"):
+                parent.selected_profile_name = self._original_profile_name
+            if hasattr(self, "_original_mixed_voice_state"):
+                parent.mixed_voice_state = self._original_mixed_voice_state
         # Prompt to save if unsaved changes, then check for zero-weight error after save
         if self._has_unsaved_changes():
             if not self._prompt_save_changes():
@@ -943,6 +969,7 @@ class VoiceFormulaDialog(QDialog):
 
     def new_profile(self):
         import re
+
         while True:
             name, ok = QInputDialog.getText(self, "New Profile", "Enter profile name:")
             if not ok or not name:
@@ -950,8 +977,12 @@ class VoiceFormulaDialog(QDialog):
             name = name.strip()  # Remove leading/trailing spaces
             if not name:
                 continue
-            if not re.match(r'^[\w\- ]+$', name):
+            if not re.match(r"^[\w\- ]+$", name):
-                QMessageBox.warning(self, "Invalid Name", "Profile name can only contain letters, numbers, spaces, underscores, and hyphens.")
+                QMessageBox.warning(
+                    self,
+                    "Invalid Name",
+                    "Profile name can only contain letters, numbers, spaces, underscores, and hyphens.",
+                )
                 continue
             profiles = load_profiles()
             # Remove 'New profile' placeholder if not persisted in JSON
@@ -1173,13 +1204,16 @@ class VoiceFormulaDialog(QDialog):
     def rename_profile(self, item):
         name = item.text().lstrip("*")
         # block if profile has unsaved changes and it's not a virtual New profile
-        if self._profile_dirty.get(name, False) and not (self._virtual_new_profile and name == "New profile"):
+        if self._profile_dirty.get(name, False) and not (
+            self._virtual_new_profile and name == "New profile"
+        ):
             QMessageBox.warning(
                 self, "Unsaved Changes", "Please save the profile before renaming."
             )
             return
         old = item.text().lstrip("*")
         import re
+
         while True:
             new, ok = QInputDialog.getText(
                 self, "Rename Profile", f"Profile name:", text=old
@@ -1189,15 +1223,19 @@ class VoiceFormulaDialog(QDialog):
             new = new.strip()  # Remove leading/trailing spaces
             if not new:
                 continue
-            if not re.match(r'^[\w\- ]+$', new):
+            if not re.match(r"^[\w\- ]+$", new):
-                QMessageBox.warning(self, "Invalid Name", "Profile name can only contain letters, numbers, spaces, underscores, and hyphens.")
+                QMessageBox.warning(
+                    self,
+                    "Invalid Name",
+                    "Profile name can only contain letters, numbers, spaces, underscores, and hyphens.",
+                )
                 continue
-            
+
             profiles = load_profiles()
             if new in profiles:
                 QMessageBox.warning(self, "Duplicate Name", "Profile already exists.")
                 continue
-                
+
             # Special case for renaming the virtual "New profile"
             if self._virtual_new_profile and name == "New profile":
                 # Create the profile with the new name
@@ -1206,12 +1244,12 @@ class VoiceFormulaDialog(QDialog):
                     "language": self.language_combo.currentData(),
                 }
                 save_profiles(profiles)
-                
+
                 # Update tracking properties
                 self._virtual_new_profile = False
                 self._profile_dirty.pop("New profile", None)
                 self._profile_dirty[new] = False
-                
+
                 # Update the current profile name
                 self.current_profile = new
                 item.setText(new)
@@ -1220,11 +1258,11 @@ class VoiceFormulaDialog(QDialog):
                 profiles[new] = profiles.pop(old)
                 save_profiles(profiles)
                 item.setText(new)
-                
+
                 # Update the current profile name if it was renamed
                 if self.current_profile == old:
                     self.current_profile = new
-            
+
             parent = self.parent()
             if hasattr(parent, "populate_profiles_in_voice_combo"):
                 parent.populate_profiles_in_voice_combo()
@@ -1306,10 +1344,16 @@ class VoiceFormulaDialog(QDialog):
             item = self.profile_list.item(i)
             name = item.text().lstrip("*")
             if self._virtual_new_profile and name == "New profile":
-                item.setBackground(QColor("#fff59d"))  # yellow
+                color = QColor("#ffff00")  # yellow
+                color.setAlpha(64)  # Set transparency
+                item.setBackground(color)
             elif item.text().startswith("*"):
-                item.setBackground(QColor("#fff59d"))  # yellow
+                color = QColor("#ffff00")  # yellow
+                color.setAlpha(64)  # Set transparency
+                item.setBackground(color)
             else:
+                item.setBackground(self.profile_list.palette().base().color()) # Use default list item background
+
                 weights = profiles.get(name, {}).get("voices", [])
                 # Defensive: only sum if weights is a list of (voice, weight) pairs
                 total = 0
@@ -1322,7 +1366,45 @@ class VoiceFormulaDialog(QDialog):
                         ):
                             total += entry[1]
                 if total == 0:
-                    item.setBackground(QColor("#ffcdd2"))  # light red
+                    color = QColor("#ff0000")  # red
-                else:
+                    color.setAlpha(64)  # Set transparency
-                    item.setBackground(QColor("white"))
+                    item.setBackground(color)
         self.update_profile_save_buttons()
+
+    def preview_current_mix(self):
+        # Disable preview until playback completes
+        self.btn_preview_mix.setEnabled(False)
+        self.btn_preview_mix.setText("Loading...")
+        self._loading = True
+        parent = self.parent()
+        if parent and hasattr(parent, "preview_voice"):
+            # Apply mixed voices and selected language
+            parent.mixed_voice_state = self.get_selected_voices()
+            parent.selected_profile_name = None
+            lang = self.language_combo.currentData()
+            parent.selected_lang = lang
+            parent.subtitle_combo.setEnabled(
+                lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
+            )
+            # Reset start flag and trigger preview
+            self._started = False
+            parent.preview_voice()
+            # Poll preview_playing: wait for start then end
+            self._preview_poll_timer = QTimer(self)
+            self._preview_poll_timer.timeout.connect(self._check_preview_done)
+            self._preview_poll_timer.start(200)
+
+    def _check_preview_done(self):
+        parent = self.parent()
+        if parent and hasattr(parent, "preview_playing"):
+            # Mark when playback starts
+            if parent.preview_playing:
+                self._started = True
+                # Update button text to "Playing..." when playback starts
+                self.btn_preview_mix.setText("Playing...")
+            # Once started and then stopped, re-enable
+            elif getattr(self, "_started", False):
+                self.btn_preview_mix.setEnabled(True)
+                self.btn_preview_mix.setText("Preview")
+                self._loading = False
+                self._preview_poll_timer.stop()

abogen/voice_profiles.py

@@ -1,6 +1,6 @@
 import os
 import json
-from utils import get_user_config_path, get_resource_path
+from utils import get_user_config_path
 
 
 def _get_profiles_path():

pyproject.toml

@@ -22,7 +22,8 @@ dependencies = [
     "soundfile>=0.13.1",
     "pygame>=2.6.1",
     "charset_normalizer>=3.4.1",
-    "chardet>=5.2.0"
+    "chardet>=5.2.0",
+    "static_ffmpeg>=2.13"
 ]
 
 classifiers = [