video-accessibility/backend/app/services
michael 54667fbcb8 fix: resolve audio/video sync issues in accessible video renderer
- Update _get_video_properties() to extract audio sample_rate, channels,
  and pix_fmt in addition to video properties
- Add _extract_segment_reencoded() for frame-accurate cuts using
  re-encoding instead of stream copy (fixes keyframe-only cut limitation)
- Add _create_freeze_segment_matched() to enforce source audio property
  matching (fixes silent pauses caused by sample rate mismatch)
- Update _render_pause_insert_method() to use new methods with uniform
  encoding parameters
- Add -video_track_timescale 90000 for consistent timebase across segments

Root causes fixed:
1. -c copy could only cut at keyframes, causing audio dropouts
2. Sample rate mismatch (48kHz source vs 44.1kHz MP3) caused silent
   freeze-frame segments when concatenated

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2025-12-26 12:05:32 -06:00
..
__pycache__ better tts config for worker 2025-10-08 18:47:28 -05:00
audit_logger.py initial commit 2025-08-24 16:28:33 -05:00
emailer.py initial commit 2025-08-24 16:28:33 -05:00
gcs.py initial commit 2025-08-24 16:28:33 -05:00
gemini.py feat: add accessible video (MP4 with embedded audio descriptions) 2025-12-26 11:06:41 -06:00
gemini_tts.py feat: add TTS settings panel with model, speed, and style options 2025-12-22 15:22:14 -06:00
microsoft_auth.py added MSAL microsoft authentication 2025-10-10 09:19:39 -05:00
secrets_manager.py initial commit 2025-08-24 16:28:33 -05:00
translate.py add support for non-English original video uploads 2025-12-22 10:33:58 -06:00
tts.py feat: add accessible video (MP4 with embedded audio descriptions) 2025-12-26 11:06:41 -06:00
validation.py initial commit 2025-08-24 16:28:33 -05:00
video_renderer.py fix: resolve audio/video sync issues in accessible video renderer 2025-12-26 12:05:32 -06:00
vtt_retimer.py feat: add accessible video (MP4 with embedded audio descriptions) 2025-12-26 11:06:41 -06:00
websocket.py wrote docker files and deployment instructions 2025-10-08 16:00:12 -05:00
websocket_publisher.py wrote docker files and deployment instructions 2025-10-08 16:00:12 -05:00