RootCommand Usageffmpegこのページの見出しffmpegInstall ArchUbuntusudo pacman -S ffmpegsudo apt install ffmpeg MP4 Manipulation with ffmpeg CommandDescriptionffmpeg -i input.mp4 -crf 30 output.mp4Compression. The higher the crf value, the higher the compression ratio.ffmpeg -i input.mp4 -an output.mp4Mute audio.