General Troubleshooting

General FFmpeg Usage

Symptom	What to check
`Unknown encoder`	Use `ffmpeg -encoders` to confirm that the encoder was built
`Invalid data found when processing input`	Check file integrity and whether the detected container format is correct
`Could not find codec parameters`	Increase `-analyzeduration` and `-probesize`, or check whether the live stream contains complete headers
`Non-monotonous DTS`	Inspect input timestamps, concatenation, remuxing, and the capture clock
Output has no audio or subtitles	Use `ffprobe` and `-map` to select streams explicitly
Output file is too large	Adjust CRF, bitrate, resolution, or frame rate
Processing is slow	Check the encoding `preset`, software filters, I/O, and hardware acceleration status

Enable detailed logging:

ffmpeg -loglevel verbose -i input.mp4 <output-options> output.mp4

Save a complete log for issue reporting:

ffmpeg -report -i input.mp4 <output-options> output.mp4