FFmpeg を使って動画ファイルをgifに変換する
概要
- 動画ファイルであるmovをgifに変換する方法をまとめる。
前提
- 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。
方法
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-1316.0.21.2.5) 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
