iOS 获取图片中的颜色-最有用最高效的方法

废话不多说，直接上代码。

创建一个UIImage的Category

#import <UIKit/UIKit.h>

@interface UIImage (ColorWithPicture)

- (UIColor*)colorWithPicture:(CGPoint)point;
@end

#import "UIImage+ColorWithPicture.h"
@implementation UIImage (ColorWithPicture)


- (UIColor *)colorWithPicture:(CGPoint)point {
    

    CFDataRef pixelData = CGDataProviderCopyData(CGImageGetDataProvider(self.CGImage));
    const UInt8 *data = CFDataGetBytePtr(pixelData);
    
    NSUInteger width = self.size.width;
    int pixelInfo = ((width * point.y) + point.x) * 4;
    
    CGFloat red   = (CGFloat)data[pixelInfo] / 255.0f;
    CGFloat green = (CGFloat)data[pixelInfo + 1] / 255.0f;
    CGFloat blue  = (CGFloat)data[pixelInfo + 2] / 255.0f;
    CGFloat alpha = (CGFloat)data[pixelInfo + 3] / 255.0f;
    
    return [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
}
@end

使用方法

UIImage *image = [UIImage imageNamed:@"image.png"];
self.view.backgroundColor = [image colorWithPicture:CGPointMake(1.0f, 1.0f)];