Priority 2: FFmpeg Volume Control
- Moved volume processing from Go to FFmpeg -af volume filter
- Eliminated CPU-intensive per-sample processing loop
- Removed ~40 lines of hot-path audio processing code
- Reduced CPU usage during playback significantly
- Dynamic volume changes restart audio seamlessly
Changes:
- Build FFmpeg command with volume filter
- Remove per-sample int16 processing loop
- Remove encoding/binary import (no longer needed)
- Add restartAudio() for dynamic volume changes
- Volume changes >5% trigger audio restart with new filter
Priority 5: Adaptive Frame Timing
- Implemented drift correction for smooth video playback
- Frame dropping when >3 frames behind schedule
- Gradual catchup when moderately behind
- Maintains smooth playback under system load
Frame Timing Logic:
- Behind < 0: Sleep until next frame (ahead of schedule)
- Behind > 3 frames: Drop frame and resync (way behind)
- Behind > 0.5 frames: Catch up gradually (moderately behind)
- Otherwise: Maintain normal pace
Performance Improvements:
- Audio: No more per-chunk volume processing overhead
- Video: Adaptive timing handles temporary slowdowns
- CPU: Significant reduction in audio processing load
- Smoothness: Better handling of system hiccups
Testing Notes:
- Audio stuttering should be greatly reduced
- Volume changes have ~200ms glitch during restart
- Frame drops logged every 30 frames to avoid spam
- Works with all frame rates (24/30/60 fps)
Still TODO (Priority 3):
- Single FFmpeg process for perfect A/V sync
- Currently separate video/audio processes can drift
Refactoring:
- Create inspect_module.go (292 lines)
- Move showInspectView() and buildInspectView()
- Reduce main.go from 14,329 to 14,116 lines (-213 lines)
- Reduce main.go from 426KB to 420KB
This is the first step in modularizing main.go to improve:
- Windows build performance (currently 5+ minutes)
- Code maintainability and organization
- Following established pattern from author_module.go and subtitles_module.go
Remaining modules to extract:
- player, compare, thumb, filters, upscale, merge, convert, queue, benchmark
Convert Module:
- Add "Add All to Queue" button when multiple videos loaded
- Batch-add all loaded videos to queue with one click
- Remove confirmation dialogs for faster workflow
- Queue button updates immediately to show new count
- Button only visible when 2+ videos are loaded
Workflow improvements:
- No more clicking through videos one by one to queue
- No "OK" confirmation clicks required
- Queue count updates instantly in View Queue button
- Auto-starts queue after adding jobs
Player Module Drag and Drop:
- Add handleDrop case for player module
- Drag video files onto player to load them
- Works the same way as convert module
- Auto-probe and load first video file from drop
Author Module:
- Enable Author module button in main menu
- Add "author" to enabled modules list (line 1525)
- Module is now clickable and functional
Seeking Fixes:
- Remove debouncing delay for immediate response
- Progress bar now seeks instantly when clicked or dragged
- No more 150ms lag during playback navigation
Frame Stepping Fixes:
- Calculate current frame from time position (current * fps)
- Previously used frameN which resets to 0 on every seek
- Frame stepping now accurately moves ±1 frame from actual position
- Buttons now work correctly regardless of seek history
Technical Details:
- currentFrame = int(p.current * p.fps) instead of p.frameN
- Removed seekTimer and seekMutex debouncing logic
- Immediate Seek() call in slider.OnChanged for responsive UX
Frame Navigation:
- Add frame-by-frame stepping with Previous/Next frame buttons
- Implement StepFrame() method for precise frame control
- Auto-pause when frame stepping for accuracy
- Display real-time frame counter during playback
Responsive Scrubbing:
- Add 150ms debounce to progress bar seeking
- Prevents rapid FFmpeg restarts during drag operations
- Smoother user experience when scrubbing through video
Player Session Improvements:
- Track frame numbers accurately with frameFunc callback
- Add duration field for proper frame calculations
- Update frame counter in real-time during playback
- Display current frame number in UI (Frame: N)
UI Enhancements:
- Frame step buttons: ◀| (previous) and |▶ (next)
- Frame counter label with monospace styling
- Integrated into existing player controls layout
Technical Details:
- Frame calculation: targetFrame = currentFrame ± delta
- Time conversion: offset = frameNumber / fps
- Clamp frame numbers to valid range [0, maxFrame]
- Call frameFunc callback on each displayed frame
Foundation ready for future enhancements (keyboard shortcuts, etc.)
- Add authorClips, authorSubtitles, authorOutputType fields to appState
- Create authorClip struct for video clip management
- Implement drag-and-drop support for video clips and subtitles
- Add Settings tab with output type, region, aspect ratio options
- Create Video Clips tab with file management
- Add Subtitles tab for track management
- Prepare framework for DVD/ISO generation
- Update HandleAuthor to work with drag-and-drop system
- Add comprehensive file validation and error handling
- Support for multiple video clips compilation
- Ready for chapter detection and DVD authoring implementation
- Add VTPlayer interface with microsecond precision seeking
- Implement MPV controller for frame-accurate playback
- Add VLC backend support for cross-platform compatibility
- Create FFplay wrapper to bridge existing controller
- Add factory pattern for automatic backend selection
- Implement Fyne UI wrapper with real-time controls
- Add frame extraction capabilities for preview system
- Support preview mode for trim/upscale/filter modules
- Include working demo and implementation documentation
