Image Manipulation Image Magick

When to Use This Skill

1. Resize images (single or batch)
2. Get image dimensions and metadata
3. Convert between image formats
4. Create thumbnails
5. Process wallpapers for different screen sizes
6. Batch process multiple images with specific criteria

Prerequisites

1. ImageMagick installed on the system
2. Windows: PowerShell with ImageMagick available as magick (or at C:\Program Files\ImageMagick-*\magick.exe)
3. Linux/macOS: Bash with ImageMagick installed via package manager (apt, brew, etc.)

Core Capabilities

1. Image Information

1. Get image dimensions (width x height)
2. Retrieve detailed metadata (format, color space, etc.)
3. Identify image format

2. Image Resizing

1. Resize single images
2. Batch resize multiple images
3. Create thumbnails with specific dimensions
4. Maintain aspect ratios

3. Batch Processing

1. Process images based on dimensions
2. Filter and process specific file types
3. Apply transformations to multiple files

Usage Examples

Example 0: Resolve magick executable

# Prefer ImageMagick on PATH
$magick = (Get-Command magick -ErrorAction SilentlyContinue)?.Source

# Fallback: common install pattern under Program Files
if (-not $magick) {
    $magick = Get-ChildItem "C:\\Program Files\\ImageMagick-*\\magick.exe" -ErrorAction SilentlyContinue |
        Select-Object -First 1 -ExpandProperty FullName
}

if (-not $magick) {
    throw "ImageMagick not found. Install it and/or add 'magick' to PATH."
}

# Check if magick is available on PATH
if ! command -v magick &> /dev/null; then
    echo "ImageMagick not found. Install it using your package manager:"
    echo "  Ubuntu/Debian: sudo apt install imagemagick"
    echo "  macOS: brew install imagemagick"
    exit 1
fi

Example 1: Get Image Dimensions

# For a single image
& $magick identify -format "%wx%h" path/to/image.jpg

# For multiple images
Get-ChildItem "path/to/images/*" | ForEach-Object { 
    $dimensions = & $magick identify -format "%f: %wx%hn" $_.FullName
    Write-Host $dimensions 
}

# For a single image
magick identify -format "%wx%h" path/to/image.jpg

# For multiple images
for img in path/to/images/*; do
    magick identify -format "%f: %wx%h\n" "$img"
done

# Resize a single image
& $magick input.jpg -resize 427x240 output.jpg

# Batch resize images
Get-ChildItem "path/to/images/*" | ForEach-Object { 
    & $magick $_.FullName -resize 427x240 "path/to/output/thumb_$($_.Name)"
}

# Resize a single image
magick input.jpg -resize 427x240 output.jpg

# Batch resize images
for img in path/to/images/*; do
    filename=$(basename "$img")
    magick "$img" -resize 427x240 "path/to/output/thumb_$filename"
done

# Get verbose information about an image
& $magick identify -verbose path/to/image.jpg

# Get verbose information about an image
magick identify -verbose path/to/image.jpg

Get-ChildItem "path/to/images/*" | ForEach-Object { 
    $dimensions = & $magick identify -format "%w,%h" $_.FullName
    if ($dimensions) {
        $width,$height = $dimensions -split ','
        if ([int]$width -eq 2560 -or [int]$height -eq 1440) {
            Write-Host "Processing $($_.Name)"
            & $magick $_.FullName -resize 427x240 "path/to/output/thumb_$($_.Name)"
        }
    }
}

for img in path/to/images/*; do
    dimensions=$(magick identify -format "%w,%h" "$img")
    if [[ -n "$dimensions" ]]; then
        width=$(echo "$dimensions" | cut -d',' -f1)
        height=$(echo "$dimensions" | cut -d',' -f2)
        if [[ "$width" -eq 2560 || "$height" -eq 1440 ]]; then
            filename=$(basename "$img")
            echo "Processing $filename"
            magick "$img" -resize 427x240 "path/to/output/thumb_$filename"
        fi
    fi
done

1. Always quote file paths - Use quotes around file paths that might contain spaces
2. Use the & operator (PowerShell) - Invoke the magick executable using & in PowerShell
3. Store the path in a variable (PowerShell) - Assign the ImageMagick path to $magick for cleaner code
4. Wrap in loops - When processing multiple files, use ForEach-Object (PowerShell) or for loops (Bash)
5. Verify dimensions first - Check image dimensions before processing to avoid unnecessary operations
6. Use appropriate resize flags - Consider using ! to force exact dimensions or ^ for minimum dimensions

$magick = (Get-Command magick).Source

$dimensions = & $magick identify -format "%w,%h" $_.FullName
$width,$height = $dimensions -split ','

if ([int]$width -gt 1920) {
    & $magick $_.FullName -resize 1920x1080 $outputPath
}

& $magick $_.FullName -resize 427x240 "thumbnails/thumb_$($_.Name)"

command -v magick &> /dev/null || { echo "ImageMagick required"; exit 1; }

dimensions=$(magick identify -format "%w,%h" "$img")
width=$(echo "$dimensions" | cut -d',' -f1)
height=$(echo "$dimensions" | cut -d',' -f2)

if [[ "$width" -gt 1920 ]]; then
    magick "$img" -resize 1920x1080 "$outputPath"
fi

filename=$(basename "$img")
magick "$img" -resize 427x240 "thumbnails/thumb_$filename"

1. Large batch operations may be memory-intensive
2. Some complex operations may require additional ImageMagick delegates
3. On older Linux systems, use convert instead of magick` (ImageMagick 6.x vs 7.x)