ffmpeg notes

How to normalize and then convert mono to stereo

ffmpeg -i audio.m4a -filter:a loudnorm audio1.m4a
ffmpeg -i audio1.m4a -af “pan=stereo|c0=c0|c1=c0” audio2.m4a

How to dump metadata

Try all of these to dump data from myfile.mov

ffprobe -show_entries 'stream_tags : format_tags' myfile.mov  
ffprobe -v quiet -print_format json -show_streams myfile.mov  
mdls myfile.mov  
mp4dump myfile.mov  
exiftool myfile.mov  
exiftool -v<level> myfile.mov  

<level> can be 1 through 5
mp4dump relies on the bento4 homebrew package
exiftool relies on the exiftool homebrew package

Loudness normalization

Normalize:

ffmpeg -i "IMG_0025.mov" -filter:a loudnorm output.mp4  

Then increase:

Source: https://trac.ffmpeg.org/wiki/AudioVolume

How to remove audio

Use the -an flag

How to re-compress video

Higher -crf numbers perform more compression:

ffmpeg -i input.mp4 -vcodec libx264 -crf 28 output.mp4  

source: https://unix.stackexchange.com/questions/28803/how-can-i-reduce-a-videos-size-with-ffmpeg

How to cut parts of video with no audio

See https://github.com/WyattBlue/auto-editor

How to speed up a video that doesn’t have audio

ffmpeg -i speedup.mov -filter:v "setpts=0.8*PTS" speedup2.mov   

How to speed up video and audio together without affecting voices

ffmpeg -i myvid.mp4 -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" myvid_faster.mp4  

Source: https://superuser.com/a/1394709/47546

How to create a video from images and audio

./ffmpeg -f image2 -framerate 25 -i scaled/frame%08d.png -i video/audio.mp3 -r 25 -vcodec libx264 -crf 16 video/upscaled.mp4  

Get the framerate from the original using ffprobe.
Source: https://www.youtube.com/watch?v=juuNQju0xv4
See sample project in ~/dev/upscale_video

How to get info about a video (metadata, framerate)

ffprobe myFile.mp4  

How to dump video as images

ffmpeg -i video/video.mp4 frames/frame%08d.png  

How to extract audio

ffmpeg -i video.mp4 audio.mp3  

How to convert video to animated gif

ffmpeg -i myFile.mp4 -r 8 myFile.gif  

How to splice video (tutorial, splice, slice)

https://osric.com/chris/accidental-developer/2012/04/using-ffmpeg-to-programmatically-slice-and-splice-video/

How to install ffmpeg on MacOS

brew install ffmpeg

How to install ffmpeg on AL2023

wget https://ffmpeg.org/releases/ffmpeg-7.0.tar.bz2  
tar -xjvf ffmpeg-7.0.tar.bz2  
cd ffmpeg-7.0  
./configure  
make  
sudo make install  
which ffmpeg  
ffmpeg --version