ios：更改 UIImage 的颜色

ios: change the colors of a UIImage

提问by Youssef

I am working on an Iphone application.

我正在开发一个 Iphone 应用程序。

I have png pictures that represents symbols. symbols are all black with a transparent background.

我有代表符号的png图片。符号都是黑色的，背景是透明的。

Is there a way I can turn the black color into another one? What I'm looking for is something that can help me choose the color I want and when using the symbols (in a UIImage) I can make them appear the color of my choice.

有没有办法可以将黑色变成另一种颜色？我正在寻找的是可以帮助我选择我想要的颜色的东西，并且在使用符号时（在 UIImage 中）我可以让它们显示我选择的颜色。

I have searched around and found a framework called OpenCV that can manipulate images but I cant find out how to recolor the picture.

我四处搜索并找到了一个名为 OpenCV 的框架，它可以处理图像，但我无法找到如何重新着色图片。

Any help and suggestion is greatly appreciated.

非常感谢任何帮助和建议。

Thank you

谢谢

回答by skywinder

The easiest and shortest:

最简单和最短的：

Way to do that in case when you dealing with UIImageView:

在处理以下情况时的处理方法UIImageView：

Obj-C:

对象-C：

theImageView.image = [theImageView.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[theImageView setTintColor:[UIColor redColor]];

Swift:

迅速：

let theImageView = UIImageView(image: UIImage(named:"foo")!.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate))
theImageView.tintColor = UIColor.redColor()

回答by Arun

hi you want to change remove/ one specific color means use the below category....

嗨，您想更改删除/一种特定颜色意味着使用以下类别....

.h file:

.h 文件：

#import <UIKit/UIKit.h>

@interface UIImage (Color)

+ (UIImage*)setBackgroundImageByColor:(UIColor *)backgroundColor withFrame:(CGRect )rect;


+ (UIImage*) replaceColor:(UIColor*)color inImage:(UIImage*)image withTolerance:(float)tolerance;

+(UIImage *)changeWhiteColorTransparent: (UIImage *)image;

+(UIImage *)changeColorTo:(NSMutableArray*) array Transparent: (UIImage *)image;

//resizing Stuff...
+ (UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize;

@end

.m file

.m 文件

#import <QuartzCore/QuartzCore.h>
#import "UIImage+Color.h"

@implementation UIImage (Color)




+ (UIImage* )setBackgroundImageByColor:(UIColor *)backgroundColor withFrame:(CGRect )rect{

    // tcv - temporary colored view
    UIView *tcv = [[UIView alloc] initWithFrame:rect];
    [tcv setBackgroundColor:backgroundColor];


    // set up a graphics context of button's size
    CGSize gcSize = tcv.frame.size;
    UIGraphicsBeginImageContext(gcSize);
    // add tcv's layer to context
    [tcv.layer renderInContext:UIGraphicsGetCurrentContext()];
    // create background image now
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
     UIGraphicsEndImageContext();

     return image;
//    [tcv release];

}





+ (UIImage*) replaceColor:(UIColor*)color inImage:(UIImage*)image withTolerance:(float)tolerance {
    CGImageRef imageRef = [image CGImage];

    NSUInteger width = CGImageGetWidth(imageRef);
    NSUInteger height = CGImageGetHeight(imageRef);
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

    NSUInteger bytesPerPixel = 4;
    NSUInteger bytesPerRow = bytesPerPixel * width;
    NSUInteger bitsPerComponent = 8;
    NSUInteger bitmapByteCount = bytesPerRow * height;

    unsigned char *rawData = (unsigned char*) calloc(bitmapByteCount, sizeof(unsigned char));

    CGContextRef context = CGBitmapContextCreate(rawData, width, height,
                                                 bitsPerComponent, bytesPerRow, colorSpace,
                                                 kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
    CGColorSpaceRelease(colorSpace);

    CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);

    CGColorRef cgColor = [color CGColor];
    const CGFloat *components = CGColorGetComponents(cgColor);
    float r = components[0];
    float g = components[1];
    float b = components[2];
    //float a = components[3]; // not needed

    r = r * 255.0;
    g = g * 255.0;
    b = b * 255.0;

    const float redRange[2] = {
        MAX(r - (tolerance / 2.0), 0.0),
        MIN(r + (tolerance / 2.0), 255.0)
    };

    const float greenRange[2] = {
        MAX(g - (tolerance / 2.0), 0.0),
        MIN(g + (tolerance / 2.0), 255.0)
    };

    const float blueRange[2] = {
        MAX(b - (tolerance / 2.0), 0.0),
        MIN(b + (tolerance / 2.0), 255.0)
    };

    int byteIndex = 0;

    while (byteIndex < bitmapByteCount) {
        unsigned char red   = rawData[byteIndex];
        unsigned char green = rawData[byteIndex + 1];
        unsigned char blue  = rawData[byteIndex + 2];

        if (((red >= redRange[0]) && (red <= redRange[1])) &&
            ((green >= greenRange[0]) && (green <= greenRange[1])) &&
            ((blue >= blueRange[0]) && (blue <= blueRange[1]))) {
            // make the pixel transparent
            //
            rawData[byteIndex] = 0;
            rawData[byteIndex + 1] = 0;
            rawData[byteIndex + 2] = 0;
            rawData[byteIndex + 3] = 0;
        }

        byteIndex += 4;
    }

    UIImage *result = [UIImage imageWithCGImage:CGBitmapContextCreateImage(context)];

    CGContextRelease(context);
    free(rawData);

    return result;
}

+(UIImage *)changeWhiteColorTransparent: (UIImage *)image
{
    CGImageRef rawImageRef=image.CGImage;

    const float colorMasking[6] = {222, 255, 222, 255, 222, 255};

    UIGraphicsBeginImageContext(image.size);
    CGImageRef maskedImageRef=CGImageCreateWithMaskingColors(rawImageRef, colorMasking);
    {
        //if in iphone
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, image.size.height);
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0); 
    }

    CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, image.size.width, image.size.height), maskedImageRef);
    UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
    CGImageRelease(maskedImageRef);
    UIGraphicsEndImageContext();    
    return result;
}




+(UIImage *)changeColorTo:(NSMutableArray*) array Transparent: (UIImage *)image
{
    CGImageRef rawImageRef=image.CGImage;

//    const float colorMasking[6] = {222, 255, 222, 255, 222, 255};

     const float colorMasking[6] = {[[array objectAtIndex:0] floatValue], [[array objectAtIndex:1] floatValue], [[array objectAtIndex:2] floatValue], [[array objectAtIndex:3] floatValue], [[array objectAtIndex:4] floatValue], [[array objectAtIndex:5] floatValue]};


    UIGraphicsBeginImageContext(image.size);
    CGImageRef maskedImageRef=CGImageCreateWithMaskingColors(rawImageRef, colorMasking);
    {
        //if in iphone
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, image.size.height);
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0); 
    }

    CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, image.size.width, image.size.height), maskedImageRef);
    UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
    CGImageRelease(maskedImageRef);
    UIGraphicsEndImageContext();    
    return result;
}

+ (UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
    //UIGraphicsBeginImageContext(newSize);
    UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
    [image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();    
    UIGraphicsEndImageContext();
    return newImage;
}



@end

i changed the removed white color to transparent by this code....

我通过此代码将删除的白色更改为透明....

the call will be...

电话将是...

 self.rawImage.image=[UIImage changeWhiteColorTransparent:originalStateImage];

i hope this idea will help you....

我希望这个想法能帮助你......

回答by Arun

hi use this category file to change the image entire color....

嗨，使用此类别文件更改图像的整个颜色....

.h file:

.h 文件：

#import <UIKit/UIKit.h>

@interface UIImage (AddtionalFunctionalities)

//TintColor...
- (UIImage *)imageWithTint:(UIColor *)tintColor;
//scale and resize...
-(UIImage*)scaleToSize:(CGSize)size;

@end

.m file:

.m 文件：

#import "UIImage+AddtionalFunctionalities.h"

@implementation UIImage (AddtionalFunctionalities)


- (UIImage *)imageWithTint:(UIColor *)tintColor 
{
    // Begin drawing
    CGRect aRect = CGRectMake(0.f, 0.f, self.size.width, self.size.height);
    CGImageRef alphaMask;

    //
    // Compute mask flipping image
    //
    {
        UIGraphicsBeginImageContext(aRect.size);        
        CGContextRef c = UIGraphicsGetCurrentContext(); 

        // draw image
        CGContextTranslateCTM(c, 0, aRect.size.height);
        CGContextScaleCTM(c, 1.0, -1.0);
        [self drawInRect: aRect];

        alphaMask = CGBitmapContextCreateImage(c);

        UIGraphicsEndImageContext();
    }

    //
    UIGraphicsBeginImageContext(aRect.size);

    // Get the graphic context
    CGContextRef c = UIGraphicsGetCurrentContext(); 

    // Draw the image
    [self drawInRect:aRect];

    // Mask
    CGContextClipToMask(c, aRect, alphaMask);

    // Set the fill color space
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextSetFillColorSpace(c, colorSpace);

    // Set the fill color
    CGContextSetFillColorWithColor(c, tintColor.CGColor);

    UIRectFillUsingBlendMode(aRect, kCGBlendModeNormal);

    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();    

    // Release memory
    CGColorSpaceRelease(colorSpace);
    CGImageRelease(alphaMask);

    return img;
}


-(UIImage*)scaleToSize:(CGSize)size
{
    // Create a bitmap graphics context
    // This will also set it as the current context
    UIGraphicsBeginImageContext(size);

    // Draw the scaled image in the current context
    [self drawInRect:CGRectMake(0, 0, size.width, size.height)];

    // Create a new image from current context
    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

    // Pop the current context from the stack
    UIGraphicsEndImageContext();

    // Return our new scaled image
    return scaledImage;
}

@end

the method call will be :

方法调用将是：

 self.outputImage.image=[sourceImage imageWithTint:[UIColor redColor]];

if u want to use the image means use this:

如果你想使用图像意味着使用这个：

self.outputImage.image=[sourceImage imageWithTint:[UIColor colorWithPatternImage:[UIImage imageNamed: @"red.jpg"]]];

i hope this will help you...

我希望这能帮到您...

回答by Aks

Set the Image rendering mode then for color purpose use tintcolor property.

设置图像渲染模式，然后出于颜色目的使用 tintcolor 属性。

yourImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[yourImageView setTintColor:[UIColor redColor]];

yourImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[yourImageView setTintColor:[UIColor redColor]];

回答by Vasily Bodnarchuk

A very simple solution to change the color of the image. Idea: extensions for UIImage and UIImageView.

改变图像颜色的一个非常简单的解决方案。想法：UIImage 和 UIImageView 的扩展。

Swift 3, Xcode 8.1. https://stackoverflow.com/a/40884483/4488252

斯威夫特 3，Xcode 8.1。 https://stackoverflow.com/a/40884483/4488252

Code sample from my answer (link above):

我的答案中的代码示例（上面的链接）：

// use extension UIImage
newImageView = createNewImageView(x: 100)
newImageView.image =  UIImage(named: "Apple")?.imageWithColor(newColor: UIColor.blue)

// use extension UIImageView
newImageView = createNewImageView(x: 160)
newImageView.image =  UIImage(named: "Apple")
newImageView.imageColor = UIColor.green

回答by Mendy Barouk

For iOS 13.0

对于 iOS 13.0

Obj-C:

对象-C：

self.yourImageView.image = [self.yourImageView.image imageWithTintColor:[UIColor.redColor]];

Swift:

迅速：

yourImageView.image = yourImageView.image.withTintColor(UIColor.red);

If the image comes from the Asset Catalog, you can change the rendering in the Attribute Inspector

如果图像来自资产目录，您可以在 Attribute Inspector

回答by deimus

For playing with images using objective-c, mainly you have to use Quartz 2D/CoreGraphics framework. I suppose it will be the easiest way for you to accomplish your task.

对于使用objective-c 处理图像，主要你必须使用Quartz 2D/CoreGraphics 框架。我想这将是您完成任务的最简单方法。

The link to Quartz 2D guideline is here, the guideline is pretty comprehensive. Just have a look somewhere in filling the bitmap with color.

Quartz 2D 指南的链接在这里，该指南非常全面。只需看看用颜色填充位图的某个地方。

Also I've some records about the heavy image processing in my blog, you can have a look, it might be helpfull. http://levonp.blogspot.de/2012/05/quartz-getting-diff-images-of-two.html

另外我的博客里有一些关于重图处理的记录，你可以看看，它可能会有所帮助。 http://levonp.blogspot.de/2012/05/quartz-getting-diff-images-of-two.html

Of course you can do it also using more advanced stuffs like OpenGL, OpenCV, etc.

当然，您也可以使用更高级的东西，如 OpenGL、OpenCV 等来实现。

回答by Tomasz Szulc

You can create UIView which store UIImageView and change UIview background Color.

您可以创建存储 UIImageView 并更改 UIview 背景颜色的 UIView。

UIView *viewForImage = ....;
UIImageView *imageView = .....;
...

[viewForImage addSubview: imageView];
[self.view addSubview:viewForImage];
...

and then use for example

然后使用例如

[viewForImage setBackgroundColor: [UIColor redColor]];