re:Inventの画像を簡単に掲載できるようにFFmpegを使って画像を一括で圧縮した件

# 初回のみ
brew install ffmpeg

# 対象ディレクトリに移動した後実行
cd target_directory
for f in **/*.JPG; do ffmpeg -i "$f"  -q:v 18  ./min."$f"; done

$ eza
Permissions Size User           Date Modified Name
.rw-r--r--@  25k morimorikochan  3 Dec 00:24  .DS_Store
.rw-r--r--@ 2.7M morimorikochan  3 Dec 00:04  IMG_0001.JPG
.rw-r--r--@ 2.8M morimorikochan  3 Dec 00:04  IMG_0002.JPG
.rw-r--r--@ 2.2M morimorikochan  3 Dec 00:04  IMG_0003.JPG
# ...多すぎるので省略
.rw-r--r--@ 2.5M morimorikochan  3 Dec 00:04  IMG_9997.JPG
.rw-r--r--@ 2.8M morimorikochan  3 Dec 00:04  IMG_9998.JPG
.rw-r--r--@ 2.5M morimorikochan  3 Dec 00:04  IMG_9999.JPG

$ for f in **/*.JPG; do ffmpeg -i "$f"  -q:v 18  ./min."$f"; done
for f in **/*.JPG; do ffmpeg -i "$f"  -q:v 18  ./min."$f"; done
ffmpeg version 7.1 Copyright (c) 2000-2024 the FFmpeg developers
  built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)
  configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/7.1_3 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --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-audiotoolbox --enable-neon
  libavutil      59. 39.100 / 59. 39.100
  libavcodec     61. 19.100 / 61. 19.100
  libavformat    61.  7.100 / 61.  7.100
  libavdevice    61.  3.100 / 61.  3.100
  libavfilter    10.  4.100 / 10.  4.100
  libswscale      8.  3.100 /  8.  3.100
  libswresample   5.  3.100 /  5.  3.100
  libpostproc    58.  3.100 / 58.  3.100
Input #0, image2, from 'IMG_0001.JPG':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 542210 kb/s
  Stream #0:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 4032x3024, 25 fps, 25 tbr, 25 tbn
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> mjpeg (native))
Press [q] to stop, [?] for help
Output #0, image2, to './min.IMG_0001.JPG':
  Metadata:
    encoder         : Lavf61.7.100
  Stream #0:0: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown, progressive), 4032x3024, q=2-31, 200 kb/s, 25 fps, 25 tbn
      Metadata:
        encoder         : Lavc61.19.100 mjpeg
      Side data:
        ICC Profile
        cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: N/A
[image2 @ 0x12a704da0] The specified filename './min.IMG_0001.JPG' does not contain an image sequence pattern or a pattern is invalid.
[image2 @ 0x12a704da0] Use a pattern such as %03d for an image sequence or use the -update option (with -frames:v 1 if needed) to write a single image.
[out#0/image2 @ 0x600003e8c000] video:190KiB audio:0KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
frame=    1 fps=0.0 q=18.0 Lsize=N/A time=00:00:00.04 bitrate=N/A speed=0.442x    

# ...繰り返し