FFMpeg Cheatsheet

Source

Basic conversion

ffmpeg -i in.mp4 out.avi

See a List of Codecs

ffmpeg -codecs

Remux an MKV file into MP4

ffmpeg -i in.mkv -c:v copy -c:a copy out.mp4

High-quality encoding

Use the crf (Constant Rate Factor) parameter to control the output quality. The lower crf, the higher the quality (range: 0-51). The default value is 23, and visually lossless compression corresponds to -crf 18. Use the preset parameter to control the speed of the compression process. Additional info: https://trac.ffmpeg.org/wiki/Encode/H.264

ffmpeg -i in.mp4 -preset slower -crf 18 out.mp4

Trimming

Without re-encoding:

ffmpeg -ss [start] -i in.mp4 -t [duration] -c copy out.mp4

With re-encoding:

If you leave out the -c copy option, ffmpeg will automatically re-encode the output video and audio according to the format you chose. For high quality video and audio, read the x264 Encoding Guide and the AAC Encoding Guide, respectively.

For example:

ffmpeg -ss [start] -i in.mp4 -t [duration] -c:v libx264 -c:a aac -strict experimental -b:a 128k out.mp4

Mux video and audio from another video

To copy the video from in0.mp4 and audio from in1.mp4:

ffmpeg -i in0.mp4 -i in1.mp4 -c copy -map 0:0 -map 1:1 -shortest out.mp4

Concat demuxer

First, make a text file.

file 'in1.mp4'
file 'in2.mp4'
file 'in3.mp4'
file 'in4.mp4'

Then, run ffmpeg:

ffmpeg -f concat -i list.txt -c copy out.mp4

Delay audio/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

Extract the frames from a video

To extract all frames from between 1 and 5 seconds, and also between 11 and 15 seconds:

ffmpeg -i in.mp4 -vf select='between(t,1,5)+between(t,11,15)' -vsync 0 out%d.png

To extract one frame per second only:

ffmpeg -i in.mp4 -fps=1 -vsync 0 out%d.png

Rotate a video

Rotate 90 clockwise:

ffmpeg -i in.mov -vf "transpose=1" out.mov

For the transpose parameter you can pass:

0 = 90CounterCLockwise and Vertical Flip (default)
1 = 90Clockwise
2 = 90CounterClockwise
3 = 90Clockwise and Vertical Flip

Use -vf "transpose=2,transpose=2" for 180 degrees.

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

Mute some of the audio

To replace the first 90 seconds of audio with silence:

ffmpeg -i in.mp4 -vcodec copy -af "volume=enable='lte(t,90)':volume=0" out.mp4

To replace all audio between 1'20" and 1'30" with silence:

ffmpeg -i in.mp4 -vcodec copy -af "volume=enable='between(t,80,90)':volume=0" out.mp4

Deinterlace

Deinterlacing using “yet another deinterlacing filter”.

ffmpeg -i in.mp4 -vf yadif 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

Metadata: Change the title

ffmpeg -i in.mp4 -map_metadata -1 -metadata title="My Title" -c:v copy -c:a copy out.mp4

With yt-dlp, make a clip of a video

-ss is the start time, and -s is the duration. More info here.

# Using seconds
yt-dlp \
  -f 18 \
  --external-downloader ffmpeg \
  --external-downloader-args "ffmpeg_i:-ss 00:04:56.00 -t 5" \
  "https://www.youtube.com/watch?v=rSc9xYPMAQY"

# Using timestamp
yt-dlp \
  -f 18 \
  --external-downloader ffmpeg \
  --external-downloader-args "ffmpeg_i:-ss 00:04:56.00 -to 00:05:23.00" \
  "https://www.youtube.com/watch?v=rSc9xYPMAQY"

Creating Time-Lapse Videos

# Reduce to a smaller size (1080p) since
# "MPEG-1 does not support resolutions above 4095x4095"
for image in *.JPG; do ffmpeg -i $image -vf scale=1920:-1 ${image%.JPG}.PNG; done

# Create a movie!
ffmpeg -f image2 -pattern_type glob -i "*.PNG" output.mpg

# A lossless movie!
ffmpeg -pattern_type glob -i "*.PNG" -c:v mjpeg -qscale:v 0 output.mov

Convert FLAC to M4A

This is for macOS. You’ll need FFMpeg with this encoder. The ‘regular’ FFMPeg from HomeBrew will not work for reasons.

👉 Do not install fdk-aac-encoder to fix this issue!

brew tap homebrew-ffmpeg/ffmpeg

# or 'upgrade'. The "--HEAD" will fetch the latest release.
# Might save you trouble with ImageMagick versions.
brew install homebrew-ffmpeg/ffmpeg/ffmpeg --with-fdk-aac --HEAD

# Convert!
find . -name '*.flac' -exec sh -c 'ffmpeg -i "$1" -c:a libfdk_aac -b:a 320k "${1%.flac}.m4a"' _ {} \;

Problems

ImageMagick Version

Just install the latest ImageMagick and FFmpeg with --HEAD.

Could not find tag for codec h264 in stream #0 codec

FFmpeg is trying to transcode any cover art. To fix, just add a -c:v copy to the command above.

References