- Add abogen/domain/audio_buffer.py with core audio operations:
- create_silence(): create silence audio buffer
- mix_audio(): mix source into target buffer with auto-resize
- normalize_audio(): normalize to prevent clipping
- ensure_buffer_size(): extend buffer to minimum size
- concatenate_audio(): join multiple audio buffers
- audio_duration(): calculate duration from samples
- samples_for_duration(): calculate samples from duration
- SAMPLE_RATE constant (24000)
- Update abogen/pyqt/conversion.py:
- Import and use create_silence for chapter silence
- Use mix_audio for subtitle file mixing
- Use normalize_audio for clipping prevention
- Use create_silence for padding in subtitle processing
- Update abogen/webui/conversion_runner.py:
- Import and use create_silence in append_silence
- Replace np.zeros with domain function
- Add tests/test_audio_buffer.py with comprehensive unit tests
- Update chapter_overrides.py to return tuple matching original signature
- Import apply_chapter_overrides and merge_metadata from domain modules
- Remove old function bodies from conversion_runner.py
- Add tests/test_chapter_merge_normalize.py (19 tests)
- conversion_runner.py: 1677 → 1574 lines
- All tests pass
- Extract infer_provider_from_spec, supertonic_voice_from_spec, split_speaker_reference, formula_from_kokoro_entry, coerce_truthy to domain/voice_utils.py
- Add tests/test_voice_utils.py with 24 tests
- All tests match old behavior
- Extract build_title_intro_text and build_outro_text into domain/title_builder.py
- Uses metadata_helpers for metadata processing
- Remove _build_title_intro_text and _build_outro_text from conversion_runner.py
- Add tests/test_title_builder.py with 12 tests
- All tests match old behavior
- Remove _srt_time() and _ass_time() methods from ConversionThread
- Use _format_timestamp() from infrastructure/subtitle_writer.py instead
- Supports both SRT (ass=False) and ASS (ass=True) formats
- All existing tests pass
- Extract unified split pattern logic to domain/split_pattern.py
- Add get_split_pattern() function with language and subtitle_mode support
- Remove duplicated logic from pyqt/conversion.py
- Update pyqt/conversion.py to use domain.split_pattern.get_split_pattern
- Add tests/test_split_pattern.py with 20 tests covering English, CJK, Spanish, French, and pattern structure
- Extract SubtitleWriter classes (SrtWriter, AssWriter, VttWriter) to infrastructure/subtitle_writer.py
- Add create_subtitle_writer() factory function
- Remove old SubtitleWriter class and _format_timestamp from conversion_runner.py
- Use create_subtitle_writer() factory from infrastructure layer
- Add tests/test_subtitle_writer.py with 28 tests covering SrtWriter, AssWriter, VttWriter
- All tests match old _format_timestamp behavior
- Monkey-patch transformers.AlbertModel in plugins/kokoro/__init__.py before kokoro imports it
- Works with transformers 4.x (no-op) and 5.x (adds moved symbol)
- No pinning, forks, or extra files needed
- Add .gitattributes with text=auto eol=lf for all text file types
- Ensures consistent line endings across platforms
- Prevents future CRLF/LF diffs in pull requests
- Add .gitattributes with text=auto eol=lf for all text files
- Renormalize all files in index to LF line endings
- Fixes massive whitespace-only diffs between main and feature branch
- Create tests/plugins/ with auto-discovery fixtures and generic tests
- Add conftest.py with plugin_ids, loaded_plugin, host_context fixtures
- Add test_all_plugins.py with 3 test classes:
- TestAllPluginsManifest: validates manifest structure
- TestAllPluginsEngine: validates engine lifecycle contract
- TestAllPluginsCapabilities: validates capability implementation
- Update docs/testing.md with auto-discovery documentation
- Plugin-specific tests remain in tests/test_*_plugin.py for integration
New plugins in plugins/ are now automatically tested without manual test creation.
- Add to PluginManifest
- None = not declared (use VoiceLister fallback)
- () = explicitly no static voices
- Non-empty = static catalog available without Engine instantiation
- Update get_voices() to check manifest first, fall back to Engine
- Declare 54 Kokoro voices and 10 SuperTonic voices in manifests
- Remove hardcoded voice lists from engine.py files
- Engine.listVoices() now returns [] (manifest is source of truth)
- Clean up dead create_pipeline() kwargs (sample_rate, auto_download, total_steps)
- SuperTonic plugin uses internal defaults
- total_steps is per-request parameter via Pipeline.__call__() kwargs
- Add clear_preview_pipelines() for resource cleanup
- Fix test mocks to override listVoices()
- Update Architecture Amendment #1 doc
- Add 96 behavioral regression tests parametrized for both Kokoro and SuperTonic
- Remove legacy TTSBackendRegistry tests (13) from behavioral suite
- Remove mock-only capability tests (Preview, Streaming, Cancellation) not implemented by either plugin
- Fix get_voices() to pass required args to create_engine() + error handling
- All 598 tests pass
Task 1: Replace hardcoded VoiceLister bypass in get_voices()
- Use PluginManager → Engine → VoiceLister instead of direct imports
- No more hardcoded imports of plugins.kokoro.engine / plugins.supertonic.engine
Task 2: Remove SuperTonic Plugin dependency on legacy backend
- Create self-contained plugins/supertonic/pipeline.py
- Plugin no longer imports from abogen.tts_backends
Production code now has zero imports from:
- abogen.tts_backend
- abogen.tts_backend_registry
- abogen.tts_backends
- Add tests/contracts/engine_contract.py with shared Engine/Session tests
- TestKokoroEngineContract and TestSuperTonicEngineContract inherit from it
- Eliminates protocol test duplication between plugins
- Any new plugin just inherits EngineContractMixin to verify compliance
- Add PluginManager singleton for plugin discovery and engine caching
- Add CompatBackend adapter wrapping Engine/EngineSession into old create_backend() API
- Update tts_plugin/__init__.py with public exports
- Migrate preview.py and its test to use compat.create_backend
- Add integration and plugin manager contract tests
Implement first TTS plugin using new Plugin Architecture:
- plugins/kokoro/: Plugin package with manifest and entry point
- plugins/kokoro/engine.py: KokoroEngine and KokoroSession adapters
- Wraps existing KokoroBackend without modifying it
- Implements VoiceLister capability
- Satisfies Engine/EngineSession protocol
- Passes all 163 contract tests
Tests:
- Plugin loading through Plugin Loader
- Manifest validation
- Engine creation and lifecycle
- Session synthesis and dispose
- VoiceLister capability
15 new tests for Kokoro plugin.
Implement plugin loading and validation:
- loader.py: discover, import, validate plugins
- validate PLUGIN_MANIFEST, MODEL_REQUIREMENTS, create_engine
- validate api_version compatibility (major must match)
- validate capabilities (reject unknown)
- diagnostic messages for all error cases
- no partial registration after error
Test plugins:
- fake_plugin: minimal valid plugin for testing
- missing_manifest: no PLUGIN_MANIFEST
- invalid_api_version: major version mismatch
- invalid_capabilities: unknown capabilities
- missing_create_engine: no create_engine function
- import_error: raises ImportError during import
- missing_model_requirements: no MODEL_REQUIREMENTS
39 new tests covering all loader functionality.
Create public API structure for TTS Plugin Architecture:
- types.py: immutable value objects (AudioFormat, Duration, VoiceSelection, etc.)
- errors.py: EngineError hierarchy (7 typed exceptions)
- manifest.py: plugin manifest dataclasses (PluginManifest, EngineManifest, etc.)
- engine.py: Engine and EngineSession protocols
- capabilities.py: optional capability interfaces (VoiceLister, PreviewGenerator, etc.)
- host_context.py: HostContext and HttpClient protocol
- plugin.py: plugin contract (create_engine signature)
- __init__.py: public API exports
All interfaces are fully defined but contain no business logic.
API is frozen and ready for implementation in subsequent PRs.
- Add resolve_backend_for_voice() to TTSBackendRegistry
- Add module-level wrapper resolve_backend_for_voice()
- Simplify _infer_provider_from_spec() to use registry API
- Simplify _supertonic_voice_from_spec() to only normalize
- Add 11 test cases for the new method
Resolution rules:
1. Empty spec -> fallback
2. Kokoro formula (* or +) -> kokoro
3. Exact voice ID match -> backend id
4. Unknown voice -> fallback
Add TTSBackendRegistry.is_registered() and module-level
is_registered_backend() to validate backend IDs dynamically.
Replace all Category A hardcoded sets (validation-only) in
voice_profiles, api routes, conversion_runner, and form utils.
Make the Kokoro voice list an internal implementation detail of the
backend instead of a shared constant. The rest of the project already
accesses voices via get_metadata('kokoro').voices.
- Move VOICES_INTERNAL from constants.py to kokoro.py as _VOICES_INTERNAL
- Update tests to use get_metadata('kokoro').voices instead of importing
the constant directly
Replace direct VOICES_INTERNAL imports with get_metadata('kokoro').voices
from tts_backend_registry in all PyQt modules:
- abogen/pyqt/gui.py
- abogen/pyqt/predownload_gui.py
- abogen/pyqt/voice_formula_gui.py
- Add get_default_voice() helper to tts_backend_registry
- Replace all VOICES_INTERNAL imports in WebUI with get_metadata().voices
- Replace all DEFAULT_SUPERTONIC_VOICES imports in conversion_runner with get_metadata().voices
- Remove unused VOICES_INTERNAL import from voices.py
Core modules (voice_profiles, voice_formulas, voice_cache) already used
get_metadata(). This completes the WebUI migration.
Replace direct imports of VOICES_INTERNAL and DEFAULT_SUPERTONIC_VOICES
in voice_profiles, voice_formulas, and voice_cache with get_metadata()
from TTSBackendRegistry. Adds get_metadata() top-level function to
tts_backend_registry as symmetric counterpart to register_backend() and
create_backend().
Add voices field to TTSBackendMetadata so each backend's supported
voice list is part of its metadata rather than external constants.
- Add voices: tuple[str, ...] = () to TTSBackendMetadata
- Create _KOKORO_METADATA / _SUPERTONIC_METADATA as single source
of truth for both metadata property and registry registration
- Update KokoroBackend.get_available_voices() to use self.metadata.voices
- Update SupertonicBackend.get_available_voices() to use self.metadata.voices
- Add tests for voices field, metadata voice content, and unified instance identity
- Create KokoroBackend class implementing TTSBackend protocol
- Move all KPipeline interaction inside KokoroBackend
- Update LoadPipelineThread to create backend via create_backend()
- Update ConversionThread and VoicePreviewThread to accept backend
- Replace np_module/kpipeline_class parameters with single backend
- Add 24 unit tests for KokoroBackend
- KPipeline is now an internal implementation detail of KokoroBackend
Encapsulate SupertonicPipeline as an internal detail of
SupertonicBackend. The factory create_supertonic_backend() now
returns a SupertonicBackend instance instead of a raw
SupertonicPipeline, satisfying the TTSBackend protocol with
metadata, synthesize, get_available_voices, get_supported_formats,
and get_info methods. Backward-compatible __call__ delegates to
the internal pipeline.
Migrate all preview/debug/conversion pipeline creation to use
TTSBackendRegistry.create_backend() instead of direct imports:
- debug_tts_runner._load_pipeline(): Kokoro via registry
- preview.get_preview_pipeline(): Kokoro via registry
- preview.generate_preview_audio(): Supertonic via registry
- voice.get_preview_pipeline(): Kokoro via registry
- conversion_runner._load_pipeline(): both backends via registry
- conversion_runner inline pipeline creation: both via registry
- test: update mock to target tts_backend_registry.create_backend
- Add create_kokoro_backend() factory in kokoro.py
- Add create_supertonic_backend() factory in supertonic.py
- Auto-discover backend modules in __init__.py via pkgutil
- Both backends register themselves on import
- Tests verify registration and factory callables
- TTSBackendRegistry class with register(), list_backends(), get_metadata(), create_backend()
- Global registry singleton with register_backend() and create_backend() convenience functions
- Unit tests for registry operations
Moved SupertonicPipeline from abogen/tts_supertonic.py to
abogen/tts_backends/supertonic.py and load_numpy_kpipeline from
abogen/utils.py to abogen/tts_backends/kokoro.py.
Git correctly detects the Supertonic file as a rename (R),
preserving full commit history.
- New package: abogen/tts_backends/
- __init__.py (package marker)
- supertonic.py (SupertonicPipeline, moved from tts_supertonic.py)
- kokoro.py (load_numpy_kpipeline, moved from utils.py)
- abogen/utils.py: re-exports load_numpy_kpipeline for backward compat
- All imports updated to new canonical paths
- Create TTSBackend abstract base class with minimal contract
- Implement KokoroTTSBackend that maintains existing behavior
- Update conversion_runner.py to use new interface
- No behavioral changes, GUI unchanged, no new features
Artem Akymenko