ffmpeg
Table of Contents
Flags:
- -ss Start Timestamp
- -t duration
- -to End Timestamp
- -c Codec
c:vVideo Codecc:v copyDon't reencode the video
-map_metadata 0 -movflags use_metadata_tagsCopy all metadata
1. Convert all audio to mp3
for i in *.webm; do ffmpeg -i "$i" "${i%.*}.mp3"; done
2. Extract clip from audio/video file
ffmpeg -i input-file.webm -ss 00:31:04 -to 00:31:45 -c copy -map_metadata 0 clip-output.webm
ffmpeg -i [input_file] -ss [start_time] -t [duration] -c copy -map_metadata 0 [output_file]
3. Remove audio from video
ffmpeg -i $input_file -c copy -an $output_file
4. Add audio to image
image.jpg + music.mp3 = video.mp4
ffmpeg -loop 1 -i image.jpg -i music.mp3 -c:v libx264 -tune stillimage -c:a aac -b:a 192k -shortest -pix_fmt yuv420p video.mp4
5. Get media details
ffprobe -print_format json -show_format -show_streams [input_file] | less
6. Compress video
Just Re-encode with default CRF (23) and default codec (H264):
ffmpeg -i input.mp4 -map_metadata 0 -movflags use_metadata_tags output.mp4
Re-encode with codec H265 with default CRF (28) [But this sometimes gives problem with QuickTimePlayer in Mac]
ffmpeg -i input.mp4 -c:v libx265 -crf 28 -map_metadata 0 -movflags use_metadata_tags output.mp4
Uses
- H.265 format
- CRF (Constant Rate Factor) of 28 (Default for H.265)
Increasing CRF by 6 results to half of file size