FFmpeg を使って動画ファイルをgifに変換する


  • 動画ファイルであるmovをgifに変換する方法をまとめる。


  • Homebrewがインストールされ、brewコマンドが実行できる環境になっていること。


  1. 下記コマンドを実行してFFmpegをHomebrewでインストールする。

     brew install ffmpeg
  2. 下記コマンドを実行してmovをgifに変換する。

     ffmpeg -i movファイル名 生成されるgifファイル名
  3. ちなみに ffmpeg -hを実行するとコマンドの使い方を教えてくれる。

     $ ffmpeg -h
     ffmpeg version 5.1 Copyright (c) 2000-2022 the FFmpeg developers
       built with Apple clang version 13.1.6 (clang-1316.
       configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/5.1 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-neon
       libavutil      57. 28.100 / 57. 28.100
       libavcodec     59. 37.100 / 59. 37.100
       libavformat    59. 27.100 / 59. 27.100
       libavdevice    59.  7.100 / 59.  7.100
       libavfilter     8. 44.100 /  8. 44.100
       libswscale      6.  7.100 /  6.  7.100
       libswresample   4.  7.100 /  4.  7.100
       libpostproc    56.  6.100 / 56.  6.100
     Hyper fast Audio and Video encoder
     usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
     Getting help:
         -h      -- print basic options
         -h long -- print more options
         -h full -- print all options (including all format and codec specific options, very long)
         -h type=name -- print all options for the named decoder/encoder/demuxer/muxer/filter/bsf/protocol
         See man ffmpeg for detailed description of the options.
     Print help / information / capabilities:
     -L                  show license
     -h topic            show help
     -? topic            show help
     -help topic         show help
     --help topic        show help
     -version            show version
     -buildconf          show build configuration
     -formats            show available formats
     -muxers             show available muxers
     -demuxers           show available demuxers
     -devices            show available devices
     -codecs             show available codecs
     -decoders           show available decoders
     -encoders           show available encoders
     -bsfs               show available bit stream filters
     -protocols          show available protocols
     -filters            show available filters
     -pix_fmts           show available pixel formats
     -layouts            show standard channel layouts
     -sample_fmts        show available audio sample formats
     -dispositions       show available stream dispositions
     -colors             show available color names
     -sources device     list sources of the input device
     -sinks device       list sinks of the output device
     -hwaccels           show available HW acceleration methods
     Global options (affect whole program instead of just one file):
     -loglevel loglevel  set logging level
     -v loglevel         set logging level
     -report             generate a report
     -max_alloc bytes    set maximum size of a single allocated block
     -y                  overwrite output files
     -n                  never overwrite output files
     -ignore_unknown     Ignore unknown stream types
     -filter_threads     number of non-complex filter threads
     -filter_complex_threads  number of threads for -filter_complex
     -stats              print progress report during encoding
     -max_error_rate maximum error rate  ratio of decoding errors (0.0: no errors, 1.0: 100% errors) above which ffmpeg returns an error instead of success.
     -vol volume         change audio volume (256=normal)
     Per-file main options:
     -f fmt              force format
     -c codec            codec name
     -codec codec        codec name
     -pre preset         preset name
     -map_metadata outfile[,metadata]:infile[,metadata]  set metadata information of outfile from infile
     -t duration         record or transcode "duration" seconds of audio/video
     -to time_stop       record or transcode stop time
     -fs limit_size      set the limit file size in bytes
     -ss time_off        set the start time offset
     -sseof time_off     set the start time offset relative to EOF
     -seek_timestamp     enable/disable seeking by timestamp with -ss
     -timestamp time     set the recording timestamp ('now' to set the current time)
     -metadata string=string  add metadata
     -program title=string:st=number...  add program with specified streams
     -target type        specify target file type ("vcd", "svcd", "dvd", "dv" or "dv50" with optional prefixes "pal-", "ntsc-" or "film-")
     -apad               audio pad
     -frames number      set the number of frames to output
     -filter filter_graph  set stream filtergraph
     -filter_script filename  read stream filtergraph description from a file
     -reinit_filter      reinit filtergraph on input parameter changes
     -discard            discard
     -disposition        disposition
     Video options:
     -vframes number     set the number of video frames to output
     -r rate             set frame rate (Hz value, fraction or abbreviation)
     -fpsmax rate        set max frame rate (Hz value, fraction or abbreviation)
     -s size             set frame size (WxH or abbreviation)
     -aspect aspect      set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)
     -vn                 disable video
     -vcodec codec       force video codec ('copy' to copy stream)
     -timecode hh:mm:ss[:;.]ff  set initial TimeCode value.
     -pass n             select the pass number (1 to 3)
     -vf filter_graph    set video filters
     -ab bitrate         audio bitrate (please use -b:a)
     -b bitrate          video bitrate (please use -b:v)
     -dn                 disable data
     Audio options:
     -aframes number     set the number of audio frames to output
     -aq quality         set audio quality (codec-specific)
     -ar rate            set audio sampling rate (in Hz)
     -ac channels        set number of audio channels
     -an                 disable audio
     -acodec codec       force audio codec ('copy' to copy stream)
     -vol volume         change audio volume (256=normal)
     -af filter_graph    set audio filters
     Subtitle options:
     -s size             set frame size (WxH or abbreviation)
     -sn                 disable subtitle
     -scodec codec       force subtitle codec ('copy' to copy stream)
     -stag fourcc/tag    force subtitle tag/fourcc
     -fix_sub_duration   fix subtitles duration
     -canvas_size size   set canvas size (WxH or abbreviation)
     -spre preset        set the subtitle options to the indicated preset