UIImageColorPalette

UIImageColorPalette is a versatile utility for extracting the prominent colors from images in iOS. It efficiently identifies and provides the three most prevalent colors in a UIImage.

Table of Contents

• Installation
• Quick Start
• Examples
  • Example 1: Using a local image file
  • Example 2: Using a remote image URL
  • Example 3: Asynchronous retrieval
  • Example 4: Customizing the resize quality
• License

Installation

To install UIImageColorPalette, follow these steps:

1. Download: Download the UIImageColorPalette.h and UIImageColorPalette.m files.

2. Add to project: Integrate the downloaded files into your project.

3. Import the Class: Import the class wherever you want to use it:

#import "UIImageColorPalette.h"

Quick Start

Here are quick examples of how to use UIImageColorPalette to extract the color palette from an image:

Example 1: Using a local image file

// Load an image
NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"imageName" ofType:@"jpg"];
UIImage *image = [UIImage imageWithContentsOfFile:imagePath];

// Retrieve the color palette
UIImageColorPalette *palette = [image retrieveColorPaletteWithQuality:UIImageResizeQualityStandard];
if (palette) {
    NSLog(@"Color Palette: %@", palette);
} else {
    NSLog(@"Failed to retrieve color palette.");
}

// Set the background color of view
UIColor *backgroundColor = palette.primary;
self.view.backgroundColor = backgroundColor;

// Set the text color for a label
UIColor *textColor = palette.secondary;
myLabel.textColor = textColor;

Example 2: Using a remote image URL

// Load an image from a remote URL
NSURL *imageURL = [NSURL URLWithString:@"https://example.com/image.jpg"];
NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
UIImage *image = [UIImage imageWithData:imageData];

// Retrieve the color palette
UIImageColorPalette *palette = [image retrieveColorPaletteWithQuality:UIImageResizeQualityStandard];
if (palette) {
    NSLog(@"Color Palette: %@", palette);
} else {
    NSLog(@"Failed to retrieve color palette.");
}

Example 3: Asynchronous retrieval

// Load an image from a remote URL asynchronously
NSURL *imageURL = [NSURL URLWithString:@"https://example.com/image.jpg"];
dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0), ^{
    NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
    UIImage *image = [UIImage imageWithData:imageData];
    
    [image retrieveColorPaletteWithQuality:UIImageResizeQualityStandard completion:^(UIImageColorPalette *palette) {
        if (palette) {
            NSLog(@"Color Palette: %@", palette);
        } else {
            NSLog(@"Failed to retrieve color palette.");
        }
    }];
});

Example 4: Customizing the resize quality

You can use other presets besides UIImageResizeQualityStandard by using the following options:

• UIImageResizeQualityLow: Use low-quality resizing algorithm.
• UIImageResizeQualityMedium: Use medium-quality resizing algorithm.
• UIImageResizeQualityHigh: Use high-quality resizing algorithm.

// Load an image
NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"imageName" ofType:@"jpg"];
UIImage *image = [UIImage imageWithContentsOfFile:imagePath];

// Retrieve the color palette with custom resize quality
UIImageColorPalette *palette = [image retrieveColorPaletteWithQuality:UIImageResizeQualityHigh];
if (palette) {
    NSLog(@"Color Palette: %@", palette);
} else {
    NSLog(@"Failed to retrieve color palette.");
}

License

This project is licensed under the MIT License.