MP4 metadata (2025): inspect, edit, remove — safely

# 1) Remove global/container tags; keep audio/video unchanged
ffmpeg -i in.mp4 -map 0 -c copy -map_metadata -1 -movflags +faststart out_clean.mp4

# 2) Drop chapters and attached pictures (if present)
ffmpeg -i in.mp4 -map 0 -c copy -map_metadata -1 -map_chapters -1 -disposition:v:1 -attached_pic out_clean.mp4

# 3) Nuclear option with ExifTool (wipes many tags incl. XMP/GPS)
exiftool -all= -overwrite_original "out_clean.mp4"

# List everything with groups and duplicate tags
exiftool -G -a -s "input.mp4"

# Wipe all tags (keeps audio/video streams)
exiftool -all= -overwrite_original "input.mp4"

# Remove only GPS/date if needed
exiftool -GPS*= -CreateDate= -ModifyDate= -MediaCreateDate= -MediaModifyDate= "input.mp4"

name: sanitize-mp4
on:
  push:
    paths: ["media/**/*.mp4"]
jobs:
  clean:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Inspect
        run: |
          for f in media/**/*.mp4; do
            ffprobe -v quiet -print_format json -show_format -show_streams "$f" > "${f%.mp4}.json"
          done
      - name: Strip metadata
        run: |
          mkdir -p clean
          for f in media/**/*.mp4; do
            ffmpeg -i "$f" -map 0 -c copy -map_metadata -1 -map_chapters -1 -movflags +faststart "clean/${f##*/}"
          done
      - name: Verify
        run: |
          for f in clean/*.mp4; do
            mediainfo "$f" | tee "${f%.mp4}.info"
          done