Cover Art Embedding Skill

Concrete patterns for finding high-quality cover artwork, processing it for optimal size and format, and embedding it into audio and video files.

Artwork Sources

MusicBrainz Cover Art Archive (Primary)

MusicBrainz Cover Art Archive (CAA) is the authoritative source for album artwork.

Get Front Cover by Release MBID:

# Download front cover for a release
curl -s "https://coverartarchive.org/release/{mbid}/front" -o cover.jpg

# Example with real MBID
curl -s "https://coverartarchive.org/release/5c004fe3-6e96-3f43-9a85-16e5be8805fa/front" -o blue-cover.jpg

Check if Cover Exists:

# HEAD request to check without downloading
if curl -s -I "https://coverartarchive.org/release/${mbid}/front" | grep -q "200 OK"; then
  echo "Cover available"
else
  echo "No cover found"
fi

Get All Available Images:

# Get metadata for all images
curl -s "https://coverartarchive.org/release/${mbid}" | jq .

# Extract URLs for all front covers
curl -s "https://coverartarchive.org/release/${mbid}" | \
  jq -r '.images[] | select(.front == true) | .image'

# Download highest resolution front cover
url=$(curl -s "https://coverartarchive.org/release/${mbid}" | \
  jq -r '.images[] | select(.front == true) | .image' | head -1)
curl -s "$url" -o cover.jpg

fanart.tv API

fanart.tv provides high-quality artist images, album covers, and logos.

Get Artist Images:

# Requires API key from https://fanart.tv/get-an-api-key/
FANART_API_KEY="your-api-key"

# Get all artist artwork
curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}"

# Extract album cover URLs
curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}" | \
  jq -r '.albums."'"$album_mbid"'".albumcover[0].url'

# Extract artist background
curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}" | \
  jq -r '.artistbackground[0].url'

# Extract artist logo
curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}" | \
  jq -r '.hdmusiclogo[0].url'

Download Artwork:

# Download album cover
url=$(curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}" | \
  jq -r '.albums."'"$album_mbid"'".albumcover[0].url')
curl -s "$url" -o cover.jpg

Video Thumbnail Extraction

Extract cover artwork from video frames.

Using yt-dlp (if video was downloaded with thumbnail):

# Download video with thumbnail
yt-dlp --write-thumbnail --convert-thumbnails jpg "https://youtube.com/watch?v=..."

# Result: video.jpg alongside video.mp4

Using ffmpeg (extract from video):

# Extract single frame at specific time
ffmpeg -i input.mp4 -ss 00:00:10 -frames:v 1 -q:v 2 thumbnail.jpg

# Extract I-frame (best quality)
ffmpeg -i input.mp4 -vf "select=eq(pict_type\,I)" -frames:v 1 -q:v 2 thumbnail.jpg

# Extract frame at 25% into video
duration=$(ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 input.mp4)
timestamp=$(echo "$duration * 0.25" | bc)
ffmpeg -i input.mp4 -ss "$timestamp" -frames:v 1 -q:v 2 thumbnail.jpg

# Extract highest quality frame from first minute
ffmpeg -i input.mp4 -t 60 -vf "select=eq(pict_type\,I)" -vsync vfr -q:v 1 frames-%03d.jpg
# Then manually select best frame

Local Artwork Files

Scan for existing artwork in standard locations:

# Check for common filenames in album directory
for name in cover.jpg Cover.jpg folder.jpg Folder.jpg albumart.jpg AlbumArt.jpg; do
  if [ -f "$name" ]; then
    echo "Found: $name"
    break
  fi
done

# Search parent directory
if [ -f "../cover.jpg" ]; then
  cp "../cover.jpg" .
fi

# Find largest image file (likely the cover)
largest=$(find . -maxdepth 1 -type f \( -iname "*.jpg" -o -iname "*.png" \) -exec ls -s {} \; | \
  sort -rn | head -1 | awk '{print $2}')
echo "Largest image: $largest"

Image Processing

Resize for Mobile Optimization

Reduce image size for faster loading and smaller file sizes:

# Install ImageMagick
brew install imagemagick  # macOS
sudo apt install imagemagick  # Debian/Ubuntu

# Resize to 1200x1200 max (preserves aspect ratio)
convert input.jpg -resize 1200x1200 output.jpg

# Resize and optimize quality (85% JPEG quality)
convert input.jpg -resize 1200x1200 -quality 85 output.jpg

# Create thumbnail (300x300)
convert input.jpg -resize 300x300 thumbnail.jpg

# Batch resize all images in directory
for img in *.jpg; do
  convert "$img" -resize 1200x1200 -quality 85 "${img%.jpg}-resized.jpg"
done

Format Conversion

Convert between image formats:

# PNG to JPEG
convert input.png output.jpg

# WebP to JPEG
convert input.webp output.jpg

# JPEG to PNG (lossless)
convert input.jpg output.png

# Batch convert all PNG to JPEG
for img in *.png; do
  convert "$img" "${img%.png}.jpg"
done

Crop to Square

Crop non-square images to square aspect ratio:

# Center crop to square
convert input.jpg -gravity center -crop 1:1 +repage output.jpg

# Crop from top-left
convert input.jpg -crop 1200x1200+0+0 +repage output.jpg

# Smart crop (removes boring edges)
convert input.jpg -define trim:percent-background=0% -trim +repage -resize 1200x1200 output.jpg

Remove Metadata (Privacy)

Strip EXIF data before embedding:

# Remove all metadata
convert input.jpg -strip output.jpg

# Or use exiftool
exiftool -all= input.jpg

# Batch strip metadata
for img in *.jpg; do
  convert "$img" -strip "${img%.jpg}-clean.jpg"
done

Embedding Artwork

Opus Files (opustags)

# Embed cover art from JPEG file
opustags input.opus --set-cover cover.jpg -o output.opus

# In-place embedding
opustags -i input.opus --set-cover cover.jpg

# Verify embedding
opustags input.opus | grep -i picture

MP4 Files (ffmpeg)

# Embed cover as attached picture
ffmpeg -i input.mp4 -i cover.jpg \
  -map 0 -map 1 \
  -c copy \
  -disposition:v:1 attached_pic \
  output.mp4

# Embed with metadata
ffmpeg -i input.mp4 -i cover.jpg \
  -map 0 -map 1 \
  -c copy \
  -disposition:v:1 attached_pic \
  -metadata:s:v:1 title="Album cover" \
  -metadata:s:v:1 comment="Cover (front)" \
  output.mp4

# Verify embedding
ffprobe -v error -select_streams v -show_entries stream=codec_name,codec_type,disposition input.mp4

MP3 Files (ffmpeg)

# Embed cover with ID3v2.3
ffmpeg -i input.mp3 -i cover.jpg \
  -map 0 -map 1 \
  -c copy \
  -id3v2_version 3 \
  -metadata:s:v title="Album cover" \
  -metadata:s:v comment="Cover (front)" \
  output.mp3

# Verify embedding
ffmpeg -i input.mp3 -an -vcodec copy test-extracted-cover.jpg

FLAC Files (ffmpeg)

# Embed cover into FLAC
ffmpeg -i input.flac -i cover.jpg \
  -map 0 -map 1 \
  -c copy \
  -disposition:v:0 attached_pic \
  output.flac

# Using metaflac (alternative)
metaflac --import-picture-from=cover.jpg input.flac

Batch Embedding

Embed Same Cover into All Files

# Opus files in directory
for file in *.opus; do
  opustags -i "$file" --set-cover cover.jpg
  echo "Embedded: $file"
done

# MP3 files in directory
for file in *.mp3; do
  ffmpeg -i "$file" -i cover.jpg \
    -map 0 -map 1 -c copy \
    -id3v2_version 3 \
    -metadata:s:v title="Album cover" \
    "${file%.mp3}-covered.mp3"
  mv "${file%.mp3}-covered.mp3" "$file"
done

Embed Different Covers per Album

# Process album directories
for album_dir in */; do
  # Find cover in album directory
  cover=$(find "$album_dir" -maxdepth 1 -iname "cover.jpg" | head -1)

  if [ -n "$cover" ]; then
    # Embed into all Opus files in this album
    for file in "$album_dir"/*.opus; do
      opustags -i "$file" --set-cover "$cover"
    done
    echo "Processed: $album_dir"
  else
    echo "No cover found: $album_dir"
  fi
done

Download and Embed from MusicBrainz

#!/bin/bash
# Process all Opus files, download covers, embed

for file in *.opus; do
  # Extract artist and album from tags
  artist=$(opustags "$file" | grep "ARTIST=" | cut -d= -f2)
  album=$(opustags "$file" | grep "ALBUM=" | cut -d= -f2)

  # Query MusicBrainz for release MBID
  artist_enc=$(echo "$artist" | jq -sRr @uri)
  album_enc=$(echo "$album" | jq -sRr @uri)
  mbdata=$(curl -s "https://musicbrainz.org/ws/2/release/?query=artist:${artist_enc}%20AND%20release:${album_enc}&fmt=json" \
    -H "User-Agent: MediaCurator/1.0")

  mbid=$(echo "$mbdata" | jq -r '.releases[0].id')

  # Download cover
  if curl -s "https://coverartarchive.org/release/${mbid}/front" -o "/tmp/cover-${mbid}.jpg"; then
    # Embed cover
    opustags -i "$file" --set-cover "/tmp/cover-${mbid}.jpg"
    echo "Embedded cover: $file"
  else
    echo "No cover found: $file"
  fi

  # Rate limit
  sleep 1
done

Canonical Artwork Directory

From field testing: use a single

artwork/

directory for all artwork files, not scattered copies.

Directory Structure

artwork/
├── albums/
│   ├── blue.jpg
│   ├── court-and-spark.jpg
│   ├── hejira.jpg
│   └── clouds.jpg
├── artists/
│   ├── joni-mitchell-1970.jpg
│   ├── joni-mitchell-1976.jpg
│   └── joni-mitchell-2000.jpg
├── live/
│   ├── isle-of-wight-1970.jpg
│   └── carnegie-hall-1969.jpg
├── logos/
│   └── joni-mitchell-logo.png
├── promotional/
│   ├── blue-era-promo.jpg
│   └── court-and-spark-promo.jpg
└── ATTRIBUTION.md

Populate Artwork Directory

# Create structure
mkdir -p artwork/{albums,artists,live,logos,promotional}

# Download album covers
cd artwork/albums
curl -s "https://coverartarchive.org/release/{mbid}/front" -o blue.jpg
curl -s "https://coverartarchive.org/release/{mbid}/front" -o court-and-spark.jpg

# Download artist images from fanart.tv
cd ../artists
curl -s "https://fanart.tv/..." -o joni-mitchell-1970.jpg

# Extract video thumbnails
cd ../live
ffmpeg -i ../../video/isle-of-wight-1970.mp4 -ss 00:01:30 -frames:v 1 -q:v 2 isle-of-wight-1970.jpg

Embed from Canonical Directory

# Reference artwork by path
for file in music/Joni\ Mitchell/Blue/*.opus; do
  opustags -i "$file" --set-cover artwork/albums/blue.jpg
done

# Or create symlink in album directory
ln -s ../../artwork/albums/blue.jpg music/Joni\ Mitchell/Blue/cover.jpg

ATTRIBUTION.md

Record source and rights for all artwork:

# Artwork Attribution

## Albums

### blue.jpg
- Source: MusicBrainz Cover Art Archive
- URL: https://coverartarchive.org/release/5c004fe3-6e96-3f43-9a85-16e5be8805fa
- License: Public Domain
- Uploaded by: user123
- Date: 2015-03-20

### court-and-spark.jpg
- Source: fanart.tv
- URL: https://fanart.tv/music/...
- License: Fair Use
- Date: 2018-07-15

## Artists

### joni-mitchell-1970.jpg
- Source: Extracted from "Live at Isle of Wight 1970" video
- License: Fair Use
- Date: 2026-02-14

## Live

### isle-of-wight-1970.jpg
- Source: Video frame extraction (ffmpeg)
- Original video: Live at Isle of Wight 1970.mp4
- License: Fair Use
- Date: 2026-02-14

Extract Embedded Artwork

From Opus Files

# opustags does not support extraction, use ffmpeg
ffmpeg -i input.opus -an -vcodec copy cover.jpg

From MP4 Files

# Extract first attached picture
ffmpeg -i input.mp4 -map 0:v -map -0:V -c copy cover.jpg

# Extract all video streams (including artwork)
ffmpeg -i input.mp4 -map 0:v -c copy "stream-%d.jpg"

From MP3 Files

# Extract cover art
ffmpeg -i input.mp3 -an -vcodec copy cover.jpg

# Using id3v2 (alternative)
id3v2 -l input.mp3  # List frames
id3v2 --APIC input.mp3 > cover.jpg  # Extract

From FLAC Files

# Extract using metaflac
metaflac --export-picture-to=cover.jpg input.flac

# Or ffmpeg
ffmpeg -i input.flac -an -vcodec copy cover.jpg

Quality Checks

Verify Artwork is Embedded

# Opus
opustags input.opus | grep -i picture

# MP4
ffprobe -v error -select_streams v -show_entries stream=disposition:stream_tags input.mp4

# MP3
ffprobe -v error -show_entries format_tags input.mp3 | grep -i picture

# Or extract and check file size
ffmpeg -i input.mp3 -an -vcodec copy test.jpg
ls -lh test.jpg  # Should be >50KB for quality cover

Check Image Dimensions

# Using identify (ImageMagick)
identify cover.jpg

# Using ffprobe
ffprobe -v error -select_streams v:0 -show_entries stream=width,height cover.jpg

Verify File Size

# Check cover file size
ls -lh cover.jpg

# Ideal: 100KB - 500KB
# Too small (<50KB): low quality
# Too large (>1MB): unnecessary bloat

Troubleshooting

Cover Not Displaying in Media Player

# Check if cover is actually embedded
ffprobe -v error -show_entries format_tags input.mp3

# Re-embed with correct disposition
ffmpeg -i input.mp4 -i cover.jpg -map 0 -map 1 -c copy \
  -disposition:v:1 attached_pic \
  output.mp4

Image Format Not Supported

# Convert to JPEG
convert input.png output.jpg

# Re-embed converted image
opustags -i input.opus --set-cover output.jpg

Image Too Large (Slow Loading)

# Resize and optimize
convert cover.jpg -resize 1200x1200 -quality 85 cover-optimized.jpg

# Re-embed optimized image
opustags -i input.opus --set-cover cover-optimized.jpg

MusicBrainz Cover Not Available

# Try fanart.tv
curl -s "https://webservice.fanart.tv/v3/music/${mbid}?api_key=${FANART_API_KEY}" | \
  jq -r '.albums."'"$album_mbid"'".albumcover[0].url'

# Or Google Images (manual)
# Or extract from video if available

Complete Workflow Example

#!/bin/bash
# Download cover from MusicBrainz, process, and embed

file="$1"

# Get album MBID from existing tags
album=$(opustags "$file" | grep "ALBUM=" | cut -d= -f2)
artist=$(opustags "$file" | grep "ARTIST=" | cut -d= -f2)

# Query MusicBrainz
artist_enc=$(echo "$artist" | jq -sRr @uri)
album_enc=$(echo "$album" | jq -sRr @uri)
mbdata=$(curl -s "https://musicbrainz.org/ws/2/release/?query=artist:${artist_enc}%20AND%20release:${album_enc}&fmt=json" \
  -H "User-Agent: MediaCurator/1.0")

mbid=$(echo "$mbdata" | jq -r '.releases[0].id')

# Download cover
cover_url="https://coverartarchive.org/release/${mbid}/front"
curl -s "$cover_url" -o "/tmp/cover-${mbid}.jpg"

# Process: resize, optimize, strip metadata
convert "/tmp/cover-${mbid}.jpg" \
  -resize 1200x1200 \
  -quality 85 \
  -strip \
  "/tmp/cover-${mbid}-processed.jpg"

# Embed into file
opustags -i "$file" --set-cover "/tmp/cover-${mbid}-processed.jpg"

# Save to canonical directory
artist_safe=$(echo "$artist" | tr '/' '-')
album_safe=$(echo "$album" | tr '/' '-')
mkdir -p "artwork/albums"
cp "/tmp/cover-${mbid}-processed.jpg" "artwork/albums/${artist_safe}-${album_safe}.jpg"

# Update ATTRIBUTION.md
cat >> artwork/ATTRIBUTION.md <<EOF

### ${artist_safe}-${album_safe}.jpg
- Source: MusicBrainz Cover Art Archive
- URL: ${cover_url}
- MBID: ${mbid}
- Date: $(date +%Y-%m-%d)
EOF

echo "Cover embedded: $file"
echo "Saved to: artwork/albums/${artist_safe}-${album_safe}.jpg"

See Also

• Command:

  /tag-collection

• Skill:

  @metadata-tagging

• Agent:

  @Metadata Curator

• MusicBrainz CAA: https://coverartarchive.org/
• fanart.tv API: https://fanart.tv/api-docs/
• ImageMagick documentation: https://imagemagick.org/

References

• @$AIWG_ROOT/agentic/code/addons/aiwg-utils/rules/human-authorization.md — Seek explicit authorization before overwriting existing embedded artwork
• @$AIWG_ROOT/agentic/code/frameworks/media-curator/skills/metadata-tagging/SKILL.md — Metadata tagging skill used alongside cover art embedding for complete file tagging
• @$AIWG_ROOT/agentic/code/frameworks/media-curator/skills/tag-collection/SKILL.md — Tag collection skill that orchestrates metadata and artwork embedding together
• @$AIWG_ROOT/agentic/code/frameworks/media-curator/skills/integrity-verification/SKILL.md — Verify file integrity after embedding artwork