### Install JuicyPixels-extra with Stack

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Use this command to install the library using Stack.

```bash
stack install JuicyPixels-extra
```

--------------------------------

### Minimal Image Processing Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

This snippet demonstrates a basic workflow: reading an image, resizing it using bilinear interpolation, and saving the result. Ensure you have an 'input.png' file and the necessary libraries installed.

```haskell
import Codec.Picture
import Codec.Picture.Extra

main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "input.png"
  let scaled = scaleBilinear 300 300 img
  savePngImage "output.png" (ImageRGB8 scaled)
```

--------------------------------

### Install JuicyPixels-extra with Cabal

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Use this command to install the library using Cabal.

```bash
cabal install JuicyPixels-extra
```

--------------------------------

### Minimal Image Resizing Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

A basic example demonstrating how to load, resize, and save an image using Codec.Picture.Extra.

```haskell
{-# LANGUAGE OverloadedStrings #-}

import Codec.Picture
import Codec.Picture.Extra

main :: IO ()
main = do
  -- Load image
  Right (ImageRGB8 img) <- readImage "input.png"
  
  -- Transform
  let result = scaleBilinear 300 300 img
  
  -- Save
  savePngImage "output.png" (ImageRGB8 result)
```

--------------------------------

### Type-Directed Operations Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Shows how to create a square image with type-specific padding colors for RGB8 and RGBA8 pixel types.

```haskell
-- Square with type-specific padding color
squareRGB :: Image PixelRGB8 -> Image PixelRGB8
squareRGB = square (PixelRGB8 0 0 0)  -- Black padding

squareRGBA :: Image PixelRGBA8 -> Image PixelRGBA8
squareRGBA = square (PixelRGBA8 0 0 0 0)  -- Transparent padding
```

--------------------------------

### Generic Image Processor Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Demonstrates a function that works with any pixel type and its usage with specific image types.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- A function that works with any pixel type
processImage :: (Pixel a) => Image a -> Image a
processImage = flipHorizontally . crop 10 10 100 100

-- Usage with specific types
main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "photo.png"
  let result = processImage img
  savePngImage "output.png" (ImageRGB8 result)
```

--------------------------------

### Handle DynamicImage with Pattern Matching

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Example demonstrating how to read an image into a DynamicImage and then pattern match to handle specific pixel types like ImageRGB8. It scales the image and saves it, or prints an error message for unsupported types or read failures.

```haskell
import Codec.Picture
import Codec.Picture.Extra

result <- readImage "photo.png"
case result of
  Right (ImageRGB8 img) -> do
    let scaled = scaleBilinear 300 300 img
    savePngImage "scaled.png" (ImageRGB8 scaled)
  Right other -> putStrLn "Unsupported pixel type"
  Left err -> putStrLn $ "Read error: " ++ err
```

--------------------------------

### Read and Scale Image with PixelRGB16

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Example of reading a high-resolution PNG image and scaling it using bilinear interpolation. Assumes the image is of type ImageRGB16.

```haskell
-- Used in Codec.Picture.Extra
Right (ImageRGB16 img) <- readImage "hires-photo.png"
let scaled = scaleBilinear 512 512 img
```

--------------------------------

### Image Usage Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Demonstrates loading an image, accessing its dimensions, and constructing a new image manually. The Image type is central to image processing operations.

```haskell
import Codec.Picture

-- Load an image
Right (ImageRGB8 img) <- readImage "photo.png"
-- Type of img: Image PixelRGB8

let w = imageWidth img    -- :: Int
let h = imageHeight img   -- :: Int

-- Construct an image manually
let newImg = generateImage (\x y -> PixelRGB8 x y 0) 100 100
-- Type of newImg: Image PixelRGB8
```

--------------------------------

### Example Usage of Safe Image Operations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Demonstrates how to use the safeScale function for image resizing and handles the case where scaling might fail due to invalid dimensions. Requires Codec.Picture and Codec.Picture.Extra.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Usage
main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "input.png"
  case safeScale 200 200 img of
    Just scaled -> savePngImage "output.png" (ImageRGB8 scaled)
    Nothing -> putStrLn "Invalid dimensions"
```

--------------------------------

### PixelRGB8 Usage Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Illustrates creating black, white, and red PixelRGB8 values and using them with the `square` function for padding. PixelRGB8 is suitable for general image manipulation tasks.

```haskell
let black = PixelRGB8 0 0 0
let white = PixelRGB8 255 255 255
let red = PixelRGB8 255 0 0

-- Used in Codec.Picture.Extra
Right (ImageRGB8 img) <- readImage "photo.png"
let padded = square (PixelRGB8 128 128 128) img  -- Pad with gray
```

--------------------------------

### Web API Endpoint for Generating Thumbnails

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

An example of a web API endpoint that generates a square thumbnail for an image, applying a background color and resizing. Returns the thumbnail as a PNG ByteString. Requires Codec.Picture and Codec.Picture.Extra.

```haskell
-- Handle thumbnail request
thumbnailEndpoint :: FilePath -> IO (Maybe ByteString)
thumbnailEndpoint path = do
  result <- readImage path
  case result of
    Right (ImageRGB8 img) -> do
      let thumb = square (PixelRGB8 200 200 200)
                . scaleBilinear 128 128
                $ img
      return $ Just (encodePng (ImageRGB8 thumb))
    _ -> return Nothing
```

--------------------------------

### Web API Endpoint for Image Resizing

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

An example of a web API endpoint that resizes an image to specified dimensions and returns the result as a PNG ByteString. Handles RGB8 images and returns Nothing on failure. Requires Codec.Picture and Codec.Picture.Extra.

```haskell
-- Example structure for web API that serves images
import Codec.Picture
import Codec.Picture.Extra

-- Handle image resize request
resizeEndpoint :: Int -> Int -> FilePath -> IO (Maybe ByteString)
resizeEndpoint w h path = do
  result <- readImage path
  case result of
    Right (ImageRGB8 img) -> do
      let scaled = scaleBilinear w h img
      return $ Just (encodePng (ImageRGB8 scaled))
    _ -> return Nothing
```

--------------------------------

### PixelRGBA8 Usage Example

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Shows the creation of transparent, opaque red, and semi-transparent PixelRGBA8 values. This type is used with functions like `trim` and `square` for image editing, particularly when alpha channels are involved.

```haskell
let transparent = PixelRGBA8 0 0 0 0
let opaque_red = PixelRGBA8 255 0 0 255
let semi_transparent = PixelRGBA8 255 255 255 128

-- Used in Codec.Picture.Extra
Right (ImageRGBA8 img) <- readImage "icon.png"
let trimmed = trim img  -- Removes transparent edges
let squared = square (PixelRGBA8 0 0 0 0) img  -- Pad with transparent pixels
```

--------------------------------

### Run Tests with Stack

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

To run the comprehensive tests included in the library, use the `stack test` command.

```bash
stack test
```

--------------------------------

### Import JuicyPixels Types

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

All core types are available from the Codec.Picture module.

```haskell
import Codec.Picture
```

--------------------------------

### Add JuicyPixels-extra to Stack project

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Add the library to your stack.yaml file for dependency management.

```yaml
extra-deps:
  - JuicyPixels-extra-0.6.0
```

--------------------------------

### Run Tests with Cabal

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

To run the comprehensive tests included in the library, use the `cabal test` command.

```bash
cabal test
```

--------------------------------

### Batch Image Resizing Workflow

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

This pattern shows how to resize multiple images in a directory using scaleBilinear. Ensure 'images' directory exists and 'resized' directory is writable.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import System.Directory (listDirectory)
import System.FilePath (takeFileName, replaceExtension)

resizeImages :: Int -> Int -> IO ()
resizeImages width height = do
  files <- listDirectory "images"
  mapM_ processFile files
  where
    processFile fname = do
      Right (ImageRGB8 img) <- readImage $ "images/" ++ fname
      let scaled = scaleBilinear width height img
      savePngImage ("resized/" ++ fname) (ImageRGB8 scaled)
```

--------------------------------

### Batch Trim and Resize PNG Images from Directory

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Processes all PNG images in an input directory by auto-trimming transparent edges and resizing them to specified dimensions. The processed images are saved to an output directory. This is useful for batch image preparation tasks.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import System.Directory (listDirectory)

-- Auto-trim all PNG images and resize to target size
trimAndResizeBatch :: 
  FilePath ->           -- Input directory
  FilePath ->           -- Output directory
  Int -> Int ->         -- Target dimensions
  IO ()
trimAndResizeBatch inDir outDir w h = do
  files <- filter (".png" `isSuffixOf`) <$> listDirectory inDir
  
  mapM_ processFile files
  where
    processFile fname = do
      let inPath = inDir ++ "/" ++ fname
      Right (ImageRGBA8 img) <- readImage inPath
      
      let trimmed = trim img
      let resized = scaleBilinear w h trimmed
      
      let outPath = outDir ++ "/" ++ fname
      savePngImage outPath (ImageRGBA8 resized)

isSuffixOf :: Eq a => [a] -> [a] -> Bool
isSuffixOf suffix str = suffix == reverse (take (length suffix) (reverse str))
```

--------------------------------

### Add JuicyPixels-extra to Cabal Project

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

To add JuicyPixels-extra to your Cabal project, include it in the `build-depends` section of your `.cabal` file.

```cabal
build-depends: JuicyPixels-extra >= 0.6 && < 0.7
```

--------------------------------

### Batch Process Icons with Auto-Trim and Resize

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Loads multiple icon images from specified file paths, applies auto-trimming and squaring, resizes them to 128x128, and arranges them into a single output image. This is ideal for creating sprite sheets or icon atlases.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Batch process icons with auto-trim
processIcons :: [FilePath] -> FilePath -> IO ()
processIcons inPaths outPath = do
  images <- mapM loadAndProcess inPaths
  savePngImage outPath (ImageRGBA8 (beside images))
  where
    loadAndProcess path = do
      Right (ImageRGBA8 img) <- readImage path
      return $ scaleBilinear 128 128 (trimAndSquare img)
```

--------------------------------

### Add JuicyPixels-extra to Stack Project

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

To add JuicyPixels-extra to your Stack project, include it in the `dependencies` section of your `package.yaml` file.

```yaml
dependencies:
  - JuicyPixels-extra >= 0.6.0
```

--------------------------------

### Chain Image Transformations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Demonstrates how to chain multiple image operations, such as scaling, rotating, and squaring, using function composition. This allows for complex image processing pipelines.

```haskell
import Codec.Picture
import Codec.Picture.Extra

Right (ImageRGB8 img) <- readImage "original.png"

-- Scale, then rotate, then add padding to square
let result = square (PixelRGB8 255 255 255) 
           . rotateRight90 
           . scaleBilinear 300 300 
           $ img

savePngImage "transformed.png" (ImageRGB8 result)
```

--------------------------------

### Batch Resize Images in a Directory

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Resizes all PNG images in a specified input directory to target dimensions and saves them to an output directory. It processes images sequentially and provides progress updates.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import System.Directory (listDirectory, createDirectoryIfMissing)
import System.FilePath (takeFileName, replaceExtension, (</>))
import Control.Monad (forM_)

-- Resize all PNG images in a directory
batchResizeDirectory :: 
  FilePath ->           -- Input directory
  FilePath ->           -- Output directory
  Int -> Int ->         -- Target width and height
  IO ()
batchResizeDirectory inDir outDir w h = do
  createDirectoryIfMissing True outDir
  files <- filter isPNG <$> listDirectory inDir
  
  forM_ (zip [1..] files) $ \(i, file) -> do
    putStrLn $ "[" ++ show i ++ "/" ++ show (length files) ++ "] " ++ file
    
    let inPath = inDir </> file
    let outPath = outDir </> file
    
    result <- readImage inPath
    case result of
      Right (ImageRGB8 img) -> do
        let scaled = scaleBilinear w h img
        savePngImage outPath (ImageRGB8 scaled)
      Right _ -> putStrLn $ "  Skipped (unsupported format)"
      Left err -> putStrLn $ "  Error: " ++ err

isPNG :: FilePath -> Bool
isPNG path = takeExtension path == ".png"

takeExtension :: FilePath -> String
takeExtension = reverse . takeWhile (/= '.') . reverse
```

--------------------------------

### Create a Contact Sheet

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Arranges multiple images into a flexible grid (contact sheet) with automatic sizing. Resizes images to a thumbnail width and arranges them per row. Requires helper `chunksOf`.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Data.List (nub)

-- Layout multiple images with automatic sizing
contactSheet :: 
  Int ->                    -- Desired thumbnail width
  Int ->                    -- Images per row
  [FilePath] ->             -- Input file paths
  FilePath ->               -- Output file path
  IO ()
contactSheet thumbWidth perRow paths outputPath = do
  -- Load and resize all images
  images <- loadImages paths
  
  let images' = map (scaleBilinear thumbWidth thumbWidth) images
  
  -- Group into rows
  let rows = chunksOf perRow images'
  
  -- Combine each row horizontally, then stack vertically
  let combined = below [beside row | row <- rows]
  
  savePngImage outputPath (ImageRGB8 combined)

loadImages :: [FilePath] -> IO [Image PixelRGB8]
loadImages paths = do
  results <- mapM readImage paths
  return [img | Right (ImageRGB8 img) <- results]

chunksOf :: Int -> [a] -> [[a]]
chunksOf _ [] = []
chunksOf n xs = take n xs : chunksOf n (drop n xs)
```

--------------------------------

### Create Side-by-Side Before/After Comparison Image

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Combines two images (representing 'before' and 'after' states) into a single image placed side-by-side. Both input images are scaled to 256x256 before being combined. Useful for visual comparisons.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Create side-by-side comparison image
beforeAfterComparison :: 
  Image PixelRGB8 ->     -- Before
  Image PixelRGB8 ->     -- After
  Image PixelRGB8        -- Side-by-side
beforeAfterComparison before after =
  beside [scaleBilinear 256 256 before, scaleBilinear 256 256 after]
```

--------------------------------

### Create an Image Grid

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Combines multiple images into a specified N×M grid. Loads images, resizes them, and arranges them using `beside` and `below` functions. Requires helper `chunksOf`.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Load all images and ensure consistent size
loadAndResize :: Int -> Int -> [FilePath] -> IO [Image PixelRGB8]
loadAndResize w h paths = do
  results <- mapM readImage paths
  return [scaleBilinear w h img | Right (ImageRGB8 img) <- results]

-- Create a 3×3 grid
createGrid :: [FilePath] -> IO ()
createGrid paths = do
  -- Load 9 images, resize to 128×128
  images <- loadAndResize 128 128 (take 9 paths)
  
  -- Split into rows of 3
  let [row1, row2, row3] = chunksOf 3 images
  
  -- Combine rows horizontally, then stack vertically
  let grid = below [beside row1, beside row2, beside row3]
  
  savePngImage "grid.png" (ImageRGB8 grid)

-- Helper function
chunksOf :: Int -> [a] -> [[a]]
chunksOf _ [] = []
chunksOf n xs = take n xs : chunksOf n (drop n xs)
```

--------------------------------

### Thumbnail Creation with Padding

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Generates a square thumbnail of a specified size with a custom background color using scaleBilinear and square. The square function adds padding to make the image square.

```haskell
import Codec.Picture
import Codec.Picture.Extra

makeThumbnail :: Int -> FilePath -> FilePath -> IO ()
makeThumbnail size inputPath outputPath = do
  Right (ImageRGB8 img) <- readImage inputPath
  let thumbnail = square (PixelRGB8 200 200 200) 
                . scaleBilinear size size 
                $ img
  savePngImage outputPath (ImageRGB8 thumbnail)
```

--------------------------------

### Generate Multiple Thumbnail Sizes

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Generates multiple thumbnail sizes for a given input image. Each thumbnail is saved with a suffix indicating its size and a '.png' extension.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import System.FilePath (replaceExtension)

-- Generate multiple thumbnail sizes from single image
generateThumbnails :: 
  FilePath ->           -- Input image path
  [(Int, String)] ->    -- [(size, suffix)] e.g. [(256, "256"), (128, "128")]
  IO ()
generateThumbnails inputPath sizeSpecs = do
  Right (ImageRGB8 img) <- readImage inputPath
  
  mapM_ (generateThumbnail img) sizeSpecs
  where
    generateThumbnail img (size, suffix) = do
      let scaled = scaleBilinear size size img
      let output = replaceExtension inputPath ("_" ++ suffix ++ ".png")
      savePngImage output (ImageRGB8 scaled)

-- Usage
main :: IO ()
main = generateThumbnails "photo.png"
  [ (512, "512")
  , (256, "256")
  , (128, "128")
  , (64,  "64")
  ]
```

--------------------------------

### Generic Pipeline Builder with Type Classes

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Build reusable transformation pipelines using type classes. This allows applying the same transformation logic to images of different pixel types.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Build reusable transformation pipelines
class Transformer a where
  transform :: Image a -> Image a

instance Transformer PixelRGB8 where
  transform =
    flipHorizontally
    . crop 50 50 300 300
    . scaleBilinear 400 400

-- Usage: apply same transform to any pixel type
applyTransform :: (Transformer a) => Image a -> Image a
applyTransform = transform
```

--------------------------------

### below

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Combines multiple images vertically, stacking them on top of each other. The resulting image's height is the sum of the input images' heights, and its width is the minimum of the input images' widths.

```APIDOC
## below

### Description
Combines multiple images vertically, stacking them on top of each other. The resulting image's height is the sum of the input images' heights, and its width is the minimum of the input images' widths.

### Signature
```haskell
below :: (Pixel a) => [Image a] -> Image a
```

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```haskell
import Codec.Picture
import Codec.Picture.Extra

Right (ImageRGB8 img1) <- readImage "photo1.png"
Right (ImageRGB8 img2) <- readImage "photo2.png"
Right (ImageRGB8 img3) <- readImage "photo3.png"

-- Create a vertical stack
let combined = below [img1, img2, img3]

savePngImage "strip-vertical.png" (ImageRGB8 combined)
```

### Response
#### Success Response (200)
`Image a` — A new image with the minimum width of all input images and combined height (sum of input heights).

#### Response Example
None
```

--------------------------------

### Resize Image with Bilinear Interpolation

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Loads an image, resizes it to specified dimensions using bilinear interpolation, and saves the result. Ensure the input image is in RGB8 format.

```haskell
import Codec.Picture
import Codec.Picture.Extra

main :: IO ()
main = do
  -- Load image
  result <- readImage "photo.png"
  case result of
    Right (ImageRGB8 img) -> do
      -- Resize to 400×300
      let resized = scaleBilinear 400 300 img
      -- Save result
      savePngImage "resized.png" (ImageRGB8 resized)
    Right other -> putStrLn "Unsupported format"
    Left err -> putStrLn $ "Error: " ++ err
```

--------------------------------

### Property-Based Testing for Image Rotations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Verify that rotating an image left by 90 degrees and then right by 90 degrees results in the original image. This snippet requires the Codec.Picture and Codec.Picture.Extra libraries.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Verify rotation properties
prop_rotateLeft90ThenRight90IsIdentity :: Image PixelRGB8 -> Bool
prop_rotateLeft90ThenRight90IsIdentity img =
  imagesEqual img (rotateRight90 (rotateLeft90 img))
```

--------------------------------

### Image Batching Utility Functions

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Utility functions for loading and saving multiple images at once. Use these for batch processing tasks where you need to read or write a list of image files.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Control.Monad (mapM)

-- Load multiple images at once
loadImages :: [FilePath] -> IO [Image PixelRGB8]
loadImages paths = do
  results <- mapM readImage paths
  return [img | Right (ImageRGB8 img) <- results]

-- Save multiple images
saveImages :: [(Image PixelRGB8, FilePath)] -> IO ()
saveImages = mapM_ (uncurry savePngImage)
```

--------------------------------

### Compare Images for Equality in Tests

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Compare two images for equality based on dimensions and pixel data. This is a fundamental utility for testing image processing functions.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Foreign.Storable (Storable)

-- Compare images for equality
imagesEqual :: 
  (Eq (PixelBaseComponent a), Storable (PixelBaseComponent a)) =>
  Image a ->
  Image a ->
  Bool
imagesEqual img1 img2 =
  (imageWidth img1 == imageWidth img2) &&
  (imageHeight img1 == imageHeight img2) &&
  (imageData img1 == imageData img2)

-- Test transformation preserves dimensions
assertDimensionsPreserved :: 
  (Image PixelRGB8 -> Image PixelRGB8) ->
  Image PixelRGB8 ->
  Bool
assertDimensionsPreserved transform img =
  let result = transform img
  in imageWidth img == imageWidth result &&
     imageHeight img == imageHeight result
```

--------------------------------

### Precompute Common Image Sizes with Caching

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Cache common image sizes to avoid recomputation. Use this pattern when multiple transformations require access to images of predefined, frequently used dimensions.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Data.Map (Map, fromList, lookup)
import Prelude hiding (lookup)

-- Cache common sizes to avoid recomputation
data ThumbnailCache = ThumbnailCache
  { thumb64 :: Image PixelRGB8
  , thumb128 :: Image PixelRGB8
  , thumb256 :: Image PixelRGB8
  , full :: Image PixelRGB8
  }

makeCache :: Image PixelRGB8 -> ThumbnailCache
makeCache img = ThumbnailCache
  {
  thumb64 = scaleBilinear 64 64 img
  , thumb128 = scaleBilinear 128 128 img
  , thumb256 = scaleBilinear 256 256 img
  , full = img
  }

getThumbnail :: Int -> ThumbnailCache -> Image PixelRGB8
getThumbnail size cache
  | size <= 64 = thumb64 cache
  | size <= 128 = thumb128 cache
  | size <= 256 = thumb256 cache
  | otherwise = full cache
```

--------------------------------

### Type-Safe Polymorphic Image Resizing

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Demonstrates a generic `resize` function using `scaleBilinear` that works with any `Pixel` type. A specialized `squareWithColor` wrapper is also shown.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Generic function that works with any pixel type
resize :: (Pixel a) => Int -> Int -> Image a -> Image a
resize = scaleBilinear

-- Specialized wrapper with compile-time padding color
squareWithColor :: (Pixel a) => a -> Image a -> Image a
squareWithColor = square

-- Usage
main = do
  Right (ImageRGB8 img) <- readImage "photo.png"
  let resized = resize 200 200 img  -- Type inferred as Image PixelRGB8
  savePngImage "out.png" (ImageRGB8 resized)
```

--------------------------------

### beside

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Combines multiple images horizontally, placing them side by side. The resulting image's width is the sum of the input images' widths, and its height is the minimum of the input images' heights.

```APIDOC
## beside

### Description
Combines multiple images horizontally, placing them side by side. The resulting image's width is the sum of the input images' widths, and its height is the minimum of the input images' heights.

### Signature
```haskell
beside :: (Pixel a) => [Image a] -> Image a
```

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```haskell
import Codec.Picture
import Codec.Picture.Extra

Right (ImageRGB8 img1) <- readImage "photo1.png"
Right (ImageRGB8 img2) <- readImage "photo2.png"
Right (ImageRGB8 img3) <- readImage "photo3.png"

-- Create a horizontal strip
let combined = beside [img1, img2, img3]

savePngImage "strip-horizontal.png" (ImageRGB8 combined)
```

### Response
#### Success Response (200)
`Image a` — A new image with combined width (sum of input widths) and the minimum height of all input images.

#### Response Example
None
```

--------------------------------

### Image Grid Assembly

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Assembles a grid of images from a list of file paths using beside and below. Assumes images are in RGB8 format. The helper function chunksOf divides a list into sublists of a given size.

```haskell
import Codec.Picture
import Codec.Picture.Extra

createGrid :: [FilePath] -> FilePath -> IO ()
createGrid paths outputPath = do
  images <- mapM loadRGB8 paths
  let rows = chunksOf 3 images
  let rowImages = map beside rows
  let grid = below rowImages
  savePngImage outputPath (ImageRGB8 grid)
  where
    loadRGB8 path = do
      Right (ImageRGB8 img) <- readImage path
      return img
    chunksOf _ [] = []
    chunksOf n xs = take n xs : chunksOf n (drop n xs)
```

--------------------------------

### Generate Comparison Strip of Progressive Image Scales

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Creates a horizontal strip of images, where each image is a scaled version of the input image at a specified size. This is useful for visualizing how an image looks at different resolutions.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Show image at different scales
progressiveScales :: 
  Image PixelRGB8 ->     -- Input image
  [Int] ->               -- Sizes to show (e.g., [50, 100, 200, 400])
  Image PixelRGB8        -- Comparison strip
progressiveScales img sizes =
  beside [scaleBilinear size size img | size <- sizes]
```

--------------------------------

### Trim Constraint

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/types.md

Additionally requires that components support equality testing for detecting fully transparent pixels.

```haskell
Pixel a,
Eq (PixelBaseComponent a)
```

--------------------------------

### Module Exports for Codec.Picture.Extra

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/README.md

This module exports nine functions for image manipulation. All functions are polymorphic over pixel types.

```haskell
module Codec.Picture.Extra
  ( scaleBilinear
  , crop
  , trim
  , flipHorizontally
  , flipVertically
  , rotateLeft90
  , rotateRight90
  , rotate180
  , beside
  , below
  , square
  ) where
```

--------------------------------

### Content-Aware Trimming and Squaring

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Trims fully transparent edges from an image using trim and then makes it square with padding using square. The padding color is fully transparent black.

```haskell
trimAndSquare :: Image PixelRGBA8 -> Image PixelRGBA8
trimAndSquare img =
  let trimmed = trim img
  in square (PixelRGBA8 0 0 0 0) trimmed
```

--------------------------------

### Create a 2x2 Grid of Rotated Image Variations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Generates a single image composed of a 2x2 grid, where each cell contains a version of the input image rotated by 0, 90, 180, and 270 degrees. The input image is first resized to 200x200.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Create 2×2 grid of rotated versions
rotatedGrid :: Image PixelRGB8 -> Image PixelRGB8
rotatedGrid img =
  let size = 200
      sized = scaleBilinear size size img
      rotated0 = sized
      rotated90 = rotateRight90 sized
      rotated180 = rotate180 sized
      rotated270 = rotateLeft90 sized
  in below
      [
        beside [rotated0, rotated90]
      ,
        beside [rotated180, rotated270]
      ]
```

--------------------------------

### Scale Image with Bilinear Interpolation

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Scales an image to specified dimensions using bilinear interpolation. Ensure the input image is loaded and the desired output path is available.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Load an image
Right (ImageRGB8 img) <- readImage "photo.png"

-- Scale down to 200x200 pixels
let scaled = scaleBilinear 200 200 img

-- Write the result
savePngImage "photo-scaled.png" (ImageRGB8 scaled)
```

--------------------------------

### Build Lazy Image Transformation Pipelines

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Build a transformation pipeline without executing until needed. This is useful for composing multiple image operations that will be applied lazily.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Build transformation pipeline without executing until needed
type ImageTransform = Image PixelRGB8 -> Image PixelRGB8

-- Compose multiple transformations
buildPipeline :: [ImageTransform] -> ImageTransform
buildPipeline = foldr (.) id

-- Usage
main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "input.png"
  
  let transforms = 
        [
        scaleBilinear 300 300
        , flipHorizontally
        , rotateRight90
        ]
  
  let pipeline = buildPipeline transforms
  let result = pipeline img  -- All transforms applied here
  
  savePngImage "output.png" (ImageRGB8 result)
```

--------------------------------

### Chain Image Transformations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Applies a sequence of image transformations (horizontal flip, crop, resize) to an image loaded from a file. Assumes the input image is in RGB8 format.

```haskell
import Codec.Picture
import Codec.Picture.Extra

main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "input.png"
  
  -- Apply multiple transformations
  let result = 
        flipHorizontally
        . crop 50 50 200 200
        . scaleBilinear 300 300
        $ img
  
  savePngImage "output.png" (ImageRGB8 result)
```

--------------------------------

### Image Mirroring Utility

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Mirrors an image horizontally using flipHorizontally. This is a simple utility function for creating a mirror image.

```haskell
-- Flip to mirror image
mirror :: Image PixelRGB8 -> Image PixelRGB8
mirror = flipHorizontally
```

--------------------------------

### Combine Images Vertically

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Use `below` to stack multiple images vertically. The combined image will have a height equal to the sum of the input images' heights and a width equal to the minimum width of all input images. Ensure all images share the same pixel type and that the input list is not empty.

```haskell
import Codec.Picture
import Codec.Picture.Extra

Right (ImageRGB8 img1) <- readImage "photo1.png"
Right (ImageRGB8 img2) <- readImage "photo2.png"
Right (ImageRGB8 img3) <- readImage "photo3.png"

-- Create a vertical stack
let combined = below [img1, img2, img3]

savePngImage "strip-vertical.png" (ImageRGB8 combined)
```

--------------------------------

### Property-Based Testing for Image Trimming

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Ensure that trimming an image either reduces its dimensions or keeps them the same. This snippet requires the Codec.Picture and Codec.Picture.Extra libraries.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Verify trimming reduces or maintains size
prop_trimReducesOrMaintainsSize :: Image PixelRGBA8 -> Bool
prop_trimReducesOrMaintainsSize img =
  let trimmed = trim img
  in imageWidth trimmed <= imageWidth img &&
     imageHeight trimmed <= imageHeight img
```

--------------------------------

### Chain Image Processing Operations

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Defines a pipeline of image transformations including padding, resizing, mirroring, and cropping. This demonstrates functional composition for image manipulation.

```haskell
import Codec.Picture
import Codec.Picture.Extra

pipeline :: Image PixelRGB8 -> Image PixelRGB8
pipeline = 
  square (PixelRGB8 255 255 255)      -- Pad to square
  . scaleBilinear 256 256             -- Resize
  . flipHorizontally                  -- Mirror
  . crop 50 50 300 300                -- Extract region

main = do
  Right (ImageRGB8 img) <- readImage "input.png"
  savePngImage "output.png" (ImageRGB8 (pipeline img))
```

--------------------------------

### Pad Images to Be Square

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Pads non-square images with a specified background color to make them square using the `square` function. Useful for creating uniform thumbnails for galleries.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Pad non-square image with background color
padToSquare :: PixelRGB8 -> Image PixelRGB8 -> Image PixelRGB8
padToSquare bgColor = square bgColor

-- Apply to multiple images
padImages :: [FilePath] -> PixelRGB8 -> IO [Image PixelRGB8]
padImages paths bgColor = do
  results <- mapM readImage paths
  let images = [img | Right (ImageRGB8 img) <- results]
  return [padToSquare bgColor img | img <- images]

-- Usage: Create uniform thumbnails for gallery
main :: IO ()
main = do
  images <- padImages ["img1.png", "img2.png"] (PixelRGB8 200 200 200)
  let thumbs = map (scaleBilinear 256 256) images
  savePngImage "thumbnails.png" (ImageRGB8 (beside thumbs))
```

--------------------------------

### Safe Image Scaling with Dimension Checks

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Provides a safe way to scale an image, returning Nothing if the target dimensions are non-positive. This prevents errors from invalid scaling operations. Requires Codec.Picture and Codec.Picture.Extra.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Guard against edge cases
safeScale :: Int -> Int -> Image PixelRGB8 -> Maybe (Image PixelRGB8)
safeScale w h img
  | w <= 0 || h <= 0 = Nothing
  | otherwise = Just (scaleBilinear w h img)
```

--------------------------------

### Manual Image Cropping with crop

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Use the crop function to extract a specific rectangular region from an image using explicit coordinates and dimensions. Boundaries are automatically clamped to the image limits.

```haskell
crop :: Pixel a => Int -> Int -> Int -> Int -> Image a -> Image a
```

--------------------------------

### Combine Images Horizontally

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Use `beside` to combine a list of images into a single horizontal strip. The resulting image's width is the sum of the input images' widths, and its height is the minimum height of all input images. All input images must have the same pixel type, and the list must not be empty.

```haskell
import Codec.Picture
import Codec.Picture.Extra

Right (ImageRGB8 img1) <- readImage "photo1.png"
Right (ImageRGB8 img2) <- readImage "photo2.png"
Right (ImageRGB8 img3) <- readImage "photo3.png"

-- Create a horizontal strip
let combined = beside [img1, img2, img3]

savePngImage "strip-horizontal.png" (ImageRGB8 combined)
```

--------------------------------

### Auto-Trim Transparent Edges and Pad to Square

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Removes transparent borders from an image and then pads it to make it a square. This is useful for preparing icons or images that need a uniform aspect ratio.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Remove transparent edges and pad to square
trimAndSquare :: Image PixelRGBA8 -> Image PixelRGBA8
trimAndSquare = square (PixelRGBA8 0 0 0 0) . trim
```

--------------------------------

### Process Image Safely with Error Handling

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Reads an image, scales it, and saves it, catching potential read or processing errors. Handles unsupported pixel formats and general exceptions.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Control.Exception (catch, SomeException)

processImage :: FilePath -> Int -> Int -> IO (Either String ()) 
processImage inputPath w h = catch go handleError
  where
    go = do
      result <- readImage inputPath
      case result of
        Right (ImageRGB8 img) -> do
          let scaled = scaleBilinear w h img
          savePngImage (outputPath inputPath) (ImageRGB8 scaled)
          return $ Right ()
        Right _ -> return $ Left "Unsupported pixel format"
        Left err -> return $ Left $ "Read error: " ++ err
    
    handleError :: SomeException -> IO (Either String ())
    handleError e = return $ Left $ "Exception: " ++ show e
    
    outputPath input = "output/" ++ dropExtension (takeFileName input) ++ ".png"
```

--------------------------------

### Convert Image to Square

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/api-reference.md

Use the `square` function to convert an image into a perfect square by adding filler pixels. It supports both RGB and RGBA images, allowing for solid color or transparent padding.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- With RGB images using black padding
Right (ImageRGB8 img) <- readImage "rectangular-photo.png"
let padded = square (PixelRGB8 0 0 0) img
savePngImage "square-photo.png" (ImageRGB8 padded)

-- With RGBA images using transparent padding
Right (ImageRGBA8 img2) <- readImage "icon.png"
let padded2 = square (PixelRGBA8 0 0 0 0) img2
savePngImage "square-icon.png" (ImageRGBA8 padded2)
```

--------------------------------

### Add Watermark to a Grid of Images

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Arranges a list of images into a grid with a specified number of images per row and applies a watermark to each image. Note: The provided `addWatermark` function is a placeholder and does not actually composite the watermark.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Add a watermark to a grid of images
watermarkGrid :: 
  Image PixelRGB8 ->     -- Watermark
  Int ->                 -- Images per row
  [Image PixelRGB8] ->   -- Input images
  Image PixelRGB8        -- Output grid
watermarkGrid watermark perRow images =
  let marked = map (addWatermark watermark) images
      rows = chunksOf perRow marked
  in below [beside row | row <- rows]

-- Overlay watermark in corner (simplified: not actually overlaying)
addWatermark :: Image PixelRGB8 -> Image PixelRGB8 -> Image PixelRGB8
addWatermark _ img = img  -- In real code, use compositing
```

--------------------------------

### Parallel Batch Image Processing with Worker Pool

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Processes a list of image input/output path pairs in parallel using a specified number of worker threads. This pattern is suitable for CPU-bound image processing tasks where concurrency can improve throughput.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import System.Directory (listDirectory)
import Control.Concurrent (forkIO, newEmptyMVar, takeMVar, putMVar)
import Control.Monad (replicateM_)

-- Process images in parallel with worker pool
batchResizeParallel ::
  Int ->                -- Number of worker threads
  [(FilePath, FilePath)] -> -- [(input, output)] pairs
  Int -> Int ->         -- Target dimensions
  IO ()
batchResizeParallel workers jobs w h = do
  -- Create job queue
  queue <- newMVar jobs
  
  -- Spawn workers
  mapM_ forkIO $ replicate workers (worker queue w h)
  
  -- Wait for all jobs to complete
  return ()

worker :: MVar [(FilePath, FilePath)] -> Int -> Int -> IO ()
worker queue w h = do
  job <- takeMVar queue
  case job of
    [] -> return ()  -- No more jobs
    ((inPath, outPath) : rest) -> do
      putMVar queue rest
      
      -- Process single image
      result <- readImage inPath
      case result of
        Right (ImageRGB8 img) -> do
          let scaled = scaleBilinear w h img
          savePngImage outPath (ImageRGB8 scaled)
        _ -> return ()
      
      -- Process next job
      worker queue w h
```

--------------------------------

### Safe Image Processing with Exception Handling

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Processes an image by resizing it, with robust error handling for file reading issues, unsupported formats, and general exceptions. Exits with failure code on error.

```haskell
import Codec.Picture
import Codec.Picture.Extra
import Control.Exception (catch, SomeException)
import System.Exit (exitFailure)

processImage :: FilePath -> IO ()
processImage path = catch go handleError
  where
    go = do
      result <- readImage path
      case result of
        Right (ImageRGB8 img) ->
          savePngImage "output.png" (ImageRGB8 (scaleBilinear 200 200 img))
        Right _ -> 
          putStrLn "Unsupported pixel format" >> exitFailure
        Left err ->
          putStrLn ("Read error: " ++ err) >> exitFailure
    
    handleError :: SomeException -> IO ()
    handleError e = putStrLn ("Exception: " ++ show e) >> exitFailure

main :: IO ()
main = processImage "input.png"
```

--------------------------------

### Vertical Image Composition with below

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/module-guide.md

Combines multiple images vertically, stacking them one below the other. The resulting image's width is determined by the minimum width of the input images.

```haskell
below :: Pixel a => [Image a] -> Image a
```

--------------------------------

### Type-Specific Padding Functions

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Define type-specific padding functions for different image pixel types. Use these when you need to pad images with a specific color that matches the image's pixel type.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Type-specific padding color selection
squareRGB :: Image PixelRGB8 -> Image PixelRGB8
squareRGB = square (PixelRGB8 0 0 0)  -- Black

squareRGBA :: Image PixelRGBA8 -> Image PixelRGBA8
squareRGBA = square (PixelRGBA8 0 0 0 0)  -- Transparent

squareWhiteRGB :: Image PixelRGB8 -> Image PixelRGB8
squareWhiteRGB = square (PixelRGB8 255 255 255)  -- White

-- Usage
main :: IO ()
main = do
  Right (ImageRGB8 img) <- readImage "photo.png"
  savePngImage "squared.png" (ImageRGB8 (squareRGB img))
```

--------------------------------

### Property-Based Testing for Image Flips and Rotation

Source: https://github.com/mrkkrp/juicypixels-extra/blob/master/_autodocs/examples-and-patterns.md

Check if flipping an image horizontally and then vertically is equivalent to rotating it by 180 degrees. This snippet requires the Codec.Picture and Codec.Picture.Extra libraries.

```haskell
import Codec.Picture
import Codec.Picture.Extra

-- Verify flip composition
prop_flipBothIsRotate180 :: Image PixelRGB8 -> Bool
prop_flipBothIsRotate180 img =
  imagesEqual (rotate180 img) (flipVertically (flipHorizontally img))
```