- Detect video codec using ffprobe instead of file extensions
- Auto-enable CUDA hwaccel for supported codecs when FFMPEG_PREFER_HARDWARE=true
- Skip probing for image formats to optimize performance
- Add comprehensive tests for hardware acceleration logic
Add FFMPEG_PREFER_HARDWARE env var to enable hardware acceleration
Use h264_nvenc and hevc_nvenc encoders when hardware preferred
Fall back to software encoders (libx264/libx265) when disabled
Add comprehensive tests for hardware/software encoding modes
Update README with new environment variable documentation
This enables GPU-accelerated video encoding for better performance on systems with NVIDIA GPUs.