Ios 如何在不透明图像上用另一种颜色替换给定颜色
我想更改不透明图像的颜色。我的原始图像如下： 我想把图像转换成以下格式Ios 如何在不透明图像上用另一种颜色替换给定颜色,ios,objective-c,uiimageview,uiimage,Ios,Objective C,Uiimageview,Uiimage,我想更改不透明图像的颜色。我的原始图像如下： 我想把图像转换成以下格式 因此，基本上我想将图像中的红色颜色转换为黑色（任何其他颜色）颜色。添加以上两幅图像是为了更好地理解。您可以使用此图像。 theImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]; [theImageView setTintColor:[UIColor blackColor]]; 我觉得你的照片
因此，基本上我想将图像中的红色颜色转换为黑色（任何其他颜色）颜色。添加以上两幅图像是为了更好地理解。您可以使用此图像。
theImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[theImageView setTintColor:[UIColor blackColor]];
您可以使用此
theImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[theImageView setTintColor:[UIColor blackColor]];
cokeImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]; // yourimageviewname
[cokeImageView setTintColor:[UIColor blackColor]];
cokeImageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]; // yourimageviewname
[cokeImageView setTintColor:[UIColor blackColor]];
我看不到关于“副本”（这个问题不应该被标记为副本）的任何答案，这些副本可以让你用另一种颜色替换给定的颜色并处理不透明图像，因此我决定添加一个这样的答案。
我创建了一个
UIImage@implementation UIImage (UIImageColorReplacement)
-(UIImage*) imageByReplacingColor:(UIColor*)sourceColor withMinTolerance:(CGFloat)minTolerance withMaxTolerance:(CGFloat)maxTolerance withColor:(UIColor*)destinationColor {
// components of the source color
const CGFloat* sourceComponents = CGColorGetComponents(sourceColor.CGColor);
UInt8* source255Components = malloc(sizeof(UInt8)*4);
for (int i = 0; i < 4; i++) source255Components[i] = (UInt8)round(sourceComponents[i]*255.0);
// components of the destination color
const CGFloat* destinationComponents = CGColorGetComponents(destinationColor.CGColor);
UInt8* destination255Components = malloc(sizeof(UInt8)*4);
for (int i = 0; i < 4; i++) destination255Components[i] = (UInt8)round(destinationComponents[i]*255.0);
// raw image reference
CGImageRef rawImage = self.CGImage;
// image attributes
size_t width = CGImageGetWidth(rawImage);
size_t height = CGImageGetHeight(rawImage);
CGRect rect = {CGPointZero, {width, height}};
// bitmap format
size_t bitsPerComponent = 8;
size_t bytesPerRow = width*4;
CGBitmapInfo bitmapInfo = kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big;
// data pointer
UInt8* data = calloc(bytesPerRow, height);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
// create bitmap context
CGContextRef ctx = CGBitmapContextCreate(data, width, height, bitsPerComponent, bytesPerRow, colorSpace, bitmapInfo);
CGContextDrawImage(ctx, rect, rawImage);
// loop through each pixel's components
for (int byte = 0; byte < bytesPerRow*height; byte += 4) {
UInt8 r = data[byte];
UInt8 g = data[byte+1];
UInt8 b = data[byte+2];
// delta components
UInt8 dr = abs(r-source255Components[0]);
UInt8 dg = abs(g-source255Components[1]);
UInt8 db = abs(b-source255Components[2]);
// ratio of 'how far away' each component is from the source color
CGFloat ratio = (dr+dg+db)/(255.0*3.0);
if (ratio > maxTolerance) ratio = 1; // if ratio is too far away, set it to max.
if (ratio < minTolerance) ratio = 0; // if ratio isn't far enough away, set it to min.
// blend color components
data[byte] = (UInt8)round(ratio*r)+(UInt8)round((1.0-ratio)*destination255Components[0]);
data[byte+1] = (UInt8)round(ratio*g)+(UInt8)round((1.0-ratio)*destination255Components[1]);
data[byte+2] = (UInt8)round(ratio*b)+(UInt8)round((1.0-ratio)*destination255Components[2]);
}
// get image from context
CGImageRef img = CGBitmapContextCreateImage(ctx);
// clean up
CGContextRelease(ctx);
CGColorSpaceRelease(colorSpace);
free(data);
free(source255Components);
free(destination255Components);
UIImage* returnImage = [UIImage imageWithCGImage:img];
CGImageRelease(img);
return returnImage;
}
@end
minTolerancemaxToleranceUIImage* colaImage = [UIImage imageNamed:@"cola1.png"];
UIImage* blackColaImage = [colaImage imageByReplacingColor:[UIColor colorWithRed:1 green:0 blue:0 alpha:1] withMinTolerance:0.5 withMaxTolerance:0.6 withColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:1]];
UIImage* colaImage = [UIImage imageNamed:@"cola1.png"];
UIImage* blackColaImage = [colaImage imageByReplacingColor:[UIColor colorWithRed:1 green:0 blue:0 alpha:1] withMinTolerance:0.5 withMaxTolerance:0.6 withColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:1]];
结果是有点锯齿，但请记住，原始图像相当小。这将更好地用于更高分辨率的图像。您还可以使用公差来获得更好的结果 我看不到关于“副本”（这个问题不应该被标记为副本）的任何答案，这些副本可以让你用另一种颜色替换给定的颜色并处理不透明图像，因此我决定添加一个这样的答案。
我创建了一个
UIImage@implementation UIImage (UIImageColorReplacement)
-(UIImage*) imageByReplacingColor:(UIColor*)sourceColor withMinTolerance:(CGFloat)minTolerance withMaxTolerance:(CGFloat)maxTolerance withColor:(UIColor*)destinationColor {
// components of the source color
const CGFloat* sourceComponents = CGColorGetComponents(sourceColor.CGColor);
UInt8* source255Components = malloc(sizeof(UInt8)*4);
for (int i = 0; i < 4; i++) source255Components[i] = (UInt8)round(sourceComponents[i]*255.0);
// components of the destination color
const CGFloat* destinationComponents = CGColorGetComponents(destinationColor.CGColor);
UInt8* destination255Components = malloc(sizeof(UInt8)*4);
for (int i = 0; i < 4; i++) destination255Components[i] = (UInt8)round(destinationComponents[i]*255.0);
// raw image reference
CGImageRef rawImage = self.CGImage;
// image attributes
size_t width = CGImageGetWidth(rawImage);
size_t height = CGImageGetHeight(rawImage);
CGRect rect = {CGPointZero, {width, height}};
// bitmap format
size_t bitsPerComponent = 8;
size_t bytesPerRow = width*4;
CGBitmapInfo bitmapInfo = kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big;
// data pointer
UInt8* data = calloc(bytesPerRow, height);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
// create bitmap context
CGContextRef ctx = CGBitmapContextCreate(data, width, height, bitsPerComponent, bytesPerRow, colorSpace, bitmapInfo);
CGContextDrawImage(ctx, rect, rawImage);
// loop through each pixel's components
for (int byte = 0; byte < bytesPerRow*height; byte += 4) {
UInt8 r = data[byte];
UInt8 g = data[byte+1];
UInt8 b = data[byte+2];
// delta components
UInt8 dr = abs(r-source255Components[0]);
UInt8 dg = abs(g-source255Components[1]);
UInt8 db = abs(b-source255Components[2]);
// ratio of 'how far away' each component is from the source color
CGFloat ratio = (dr+dg+db)/(255.0*3.0);
if (ratio > maxTolerance) ratio = 1; // if ratio is too far away, set it to max.
if (ratio < minTolerance) ratio = 0; // if ratio isn't far enough away, set it to min.
// blend color components
data[byte] = (UInt8)round(ratio*r)+(UInt8)round((1.0-ratio)*destination255Components[0]);
data[byte+1] = (UInt8)round(ratio*g)+(UInt8)round((1.0-ratio)*destination255Components[1]);
data[byte+2] = (UInt8)round(ratio*b)+(UInt8)round((1.0-ratio)*destination255Components[2]);
}
// get image from context
CGImageRef img = CGBitmapContextCreateImage(ctx);
// clean up
CGContextRelease(ctx);
CGColorSpaceRelease(colorSpace);
free(data);
free(source255Components);
free(destination255Components);
UIImage* returnImage = [UIImage imageWithCGImage:img];
CGImageRelease(img);
return returnImage;
}
@end
minTolerancemaxToleranceUIImage* colaImage = [UIImage imageNamed:@"cola1.png"];
UIImage* blackColaImage = [colaImage imageByReplacingColor:[UIColor colorWithRed:1 green:0 blue:0 alpha:1] withMinTolerance:0.5 withMaxTolerance:0.6 withColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:1]];
UIImage* colaImage = [UIImage imageNamed:@"cola1.png"];
UIImage* blackColaImage = [colaImage imageByReplacingColor:[UIColor colorWithRed:1 green:0 blue:0 alpha:1] withMinTolerance:0.5 withMaxTolerance:0.6 withColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:1]];
结果是有点锯齿，但请记住，原始图像相当小。这将更好地用于更高分辨率的图像。您还可以使用公差来获得更好的结果 检查这个。。。。您只是将红色区域转换为黑色，还是将红色区域提取为新的黑色图像？我这样问是因为第二张图像没有显示出图像中的阴影first@Russell：我只想将红色区域转换为黑色。请检查此。。。。您只是将红色区域转换为黑色，还是将红色区域提取为新的黑色图像？我这样问是因为第二张图像没有显示出图像中的阴影first@Russell：我想简单地将红色区域转换为黑色。当我应用上述代码时，我的整个imageview将转换为黑色。首先工作，然后进行测试。在没有测试代码的情况下，不要给出否定标记。我总是使用这种方法。问题中的图像有白色背景，这只适用于透明PNG。您的图像中存在问题是的。MAC中支持PNG格式的实际方式在大多数情况下没有白色背景。图像应该是透明的，而不是白色背景。当我应用上面的代码时，我的整个图像视图被转换成黑色。首先，你测试它。在没有测试代码的情况下，不要给出否定标记。我总是使用这种方法。问题中的图像有白色背景，这只适用于透明PNG。您的图像中存在问题是的。MAC中支持PNG格式的实际方式在大多数情况下没有白色背景。图像应该是透明的，而不是白色背景。是的，这是我的测试代码，它正在工作。问题中的图像有白色背景，这将只在透明PNG上工作。这将显示为黑色，但实际上不会更改图像。是的，这是我的测试代码，它正在工作。问题中的图像有白色背景，这将只适用于透明PNG。这是显示为黑色，但实际上并没有改变图像。工程伟大！尝试了几个其他的解决方案，但这一个是正确的。你能用Swift 3重写它吗？肯定是最好的答案。我翻译成Swift 3作品很棒！尝试了几个其他的解决方案，但这一个是正确的。你能用Swift 3重写它吗？肯定是最好的答案。我翻译成Swift 3