add image magick skill

skills/image-manipulation-image-magick/SKILL.md

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+---
+name: image-manipulation
+description: Process and manipulate images using ImageMagick. Supports resizing, format conversion, batch processing, and retrieving image metadata. Use when working with images, creating thumbnails, resizing wallpapers, or performing batch image operations.
+compatibility: Requires ImageMagick installed and available as `magick` on PATH. Cross-platform examples provided for PowerShell (Windows) and Bash (Linux/macOS).
+---
+
+# Image Manipulation with ImageMagick
+
+This skill enables image processing and manipulation tasks using ImageMagick
+across Windows, Linux, and macOS systems.
+
+## When to Use This Skill
+
+Use this skill when you need to:
+
+- Resize images (single or batch)
+- Get image dimensions and metadata
+- Convert between image formats
+- Create thumbnails
+- Process wallpapers for different screen sizes
+- Batch process multiple images with specific criteria
+
+## Prerequisites
+
+- ImageMagick installed on the system
+- **Windows**: PowerShell with ImageMagick available as `magick` (or at `C:\Program Files\ImageMagick-*\magick.exe`)
+- **Linux/macOS**: Bash with ImageMagick installed via package manager (`apt`, `brew`, etc.)
+
+## Core Capabilities
+
+### 1. Image Information
+
+- Get image dimensions (width x height)
+- Retrieve detailed metadata (format, color space, etc.)
+- Identify image format
+
+### 2. Image Resizing
+
+- Resize single images
+- Batch resize multiple images
+- Create thumbnails with specific dimensions
+- Maintain aspect ratios
+
+### 3. Batch Processing
+
+- Process images based on dimensions
+- Filter and process specific file types
+- Apply transformations to multiple files
+
+## Usage Examples
+
+### Example 0: Resolve `magick` executable
+
+**PowerShell (Windows):**
+```powershell
+# 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."
+}
+```
+
+**Bash (Linux/macOS):**
+```bash
+# 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
+
+**PowerShell (Windows):**
+```powershell
+# 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%h`n" $_.FullName
+    Write-Host $dimensions 
+}
+```
+
+**Bash (Linux/macOS):**
+```bash
+# For a single image
+magick identify -format "%wx%h" path/to/image.jpg
+
+# For multiple images
+for img in path/to/images/*; do
+    magick identify -format "%f: %wx%h\n" "$img"
+done
+```
+
+### Example 2: Resize Images
+
+**PowerShell (Windows):**
+```powershell
+# Resize a single image
+& $magick input.jpg -resize 427x240 output.jpg
+
+# Batch resize images
+Get-ChildItem "path/to/images/*" | ForEach-Object { 
+    & $magick $_.FullName -resize 427x240 "path/to/output/thumb_$($_.Name)"
+}
+```
+
+**Bash (Linux/macOS):**
+```bash
+# Resize a single image
+magick input.jpg -resize 427x240 output.jpg
+
+# Batch resize images
+for img in path/to/images/*; do
+    filename=$(basename "$img")
+    magick "$img" -resize 427x240 "path/to/output/thumb_$filename"
+done
+```
+
+### Example 3: Get Detailed Image Information
+
+**PowerShell (Windows):**
+```powershell
+# Get verbose information about an image
+& $magick identify -verbose path/to/image.jpg
+```
+
+**Bash (Linux/macOS):**
+```bash
+# Get verbose information about an image
+magick identify -verbose path/to/image.jpg
+```
+
+### Example 4: Process Images Based on Dimensions
+
+**PowerShell (Windows):**
+```powershell
+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 $_.FullName -resize 427x240 "path/to/output/thumb_$($_.Name)"
+        }
+    }
+}
+```
+
+**Bash (Linux/macOS):**
+```bash
+for img in path/to/images/*; do
+    dimensions=$(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_$filename"
+        fi
+    fi
+done
+```
+
+## Guidelines
+
+1. **Always quote file paths** - Use quotes around file paths that might contain spaces
+2. **Use the `&` operator (PowerShell)** - Invoke the magick executable using `&` in PowerShell
+3. **Store the path in a variable (PowerShell)** - Assign the ImageMagick path to `$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
+
+## Common Patterns
+
+### PowerShell Patterns
+
+#### Pattern: Store ImageMagick Path
+
+```powershell
+$magick = (Get-Command magick).Source
+```
+
+#### Pattern: Get Dimensions as Variables
+
+```powershell
+$dimensions = & $magick identify -format "%w,%h" $_.FullName
+$width,$height = $dimensions -split ','
+```
+
+#### Pattern: Conditional Processing
+
+```powershell
+if ([int]$width -gt 1920) {
+    & $magick $_.FullName -resize 1920x1080 $outputPath
+}
+```
+
+#### Pattern: Create Thumbnails
+
+```powershell
+& $magick $_.FullName -resize 427x240 "thumbnails/thumb_$($_.Name)"
+```
+
+### Bash Patterns
+
+#### Pattern: Check ImageMagick Installation
+
+```bash
+command -v magick &> /dev/null || { echo "ImageMagick required"; exit 1; }
+```
+
+#### Pattern: Get Dimensions as Variables
+
+```bash
+dimensions=$(magick identify -format "%w,%h" "$img")
+width=$(echo "$dimensions" | cut -d',' -f1)
+height=$(echo "$dimensions" | cut -d',' -f2)
+```
+
+#### Pattern: Conditional Processing
+
+```bash
+if [[ "$width" -gt 1920 ]]; then
+    magick "$img" -resize 1920x1080 "$outputPath"
+fi
+```
+
+#### Pattern: Create Thumbnails
+
+```bash
+filename=$(basename "$img")
+magick "$img" -resize 427x240 "thumbnails/thumb_$filename"
+```
+
+## Limitations
+
+- Large batch operations may be memory-intensive
+- Some complex operations may require additional ImageMagick delegates
+- On older Linux systems, use `convert` instead of `magick` (ImageMagick 6.x vs 7.x)