FFmpeg cheat sheet

ffmpeg.md

Basic conversion

ffmpeg -i in.mp4 out.avi

Merging video and audio, without re-encoding

ffmpeg -i video.mp4 -i audio.wav -c:v copy -c:a copy output.mp4

Copying the audio without re-encoding

ffmpeg -i video.mp4 -i audio.wav -c copy output.mkv

Replacing audio stream

ffmpeg -i video.mp4 -i audio.wav -c:v copy -c:a aac -map 0:v:0 -map 1:a:0 output.mp4

Delay video

Delay video by 3.84 seconds:

ffmpeg -i in.mp4 -itsoffset 3.84 -i in.mp4 -map 1:v -map 0:a -vcodec copy -acodec copy out.mp4

Delay audio by 3.84 seconds:

ffmpeg -i in.mp4 -itsoffset 3.84 -i in.mp4 -map 0:v -map 1:a -vcodec copy -acodec copy out.mp4

Burn subtitles

Use the libass library (make sure your ffmpeg install has the library in the configuration --enable-libass).

First convert the subtitles to .ass format:

ffmpeg -i sub.srt sub.ass

Then add them using a video filter:

ffmpeg -i in.mp4 -vf ass=sub.ass out.mp4

Download "Transport Stream" video streams

1. Locate the playlist file, e.g. using Chrome > F12 > Network > Filter: m3u8
2. Download and concatenate the video fragments:

ffmpeg -i "path_to_playlist.m3u8" -c copy -bsf:a aac_adtstoasc out.mp4

If you get a "Protocol 'https not on whitelist 'file,crypto'!" error, add the protocol_whitelist option:

ffmpeg -protocol_whitelist "file,http,https,tcp,tls" -i "path_to_playlist.m3u8" -c copy -bsf:a aac_adtstoasc out.mp4

Create a video slideshow from images

Parameters: -r marks the image framerate (inverse time of each image); -vf fps=25 marks the true framerate of the output.

ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4

Extract images from a video

• Extract all frames: ffmpeg -i input.mp4 thumb%04d.jpg -hide_banner
• Extract a frame each second: ffmpeg -i input.mp4 -vf fps=1 thumb%04d.jpg -hide_banner
• Extract only one frame: ffmpeg -i input.mp4 -ss 00:00:10.000 -vframes 1 thumb.jpg

More information

https://devhints.io/ffmpeg