改变图像中的颜色物镜c

Question

我有一个黑白图像，我想在objective-c中改变蓝色的黑色和黄色的白色（例如）。

我该怎么做？

谢谢

Answer 1

您可以使用核心图像来做到这一点。

UIImage *bwImage = ... // Get your image from somewhere 
CGImageRef bwCGImage = bwImage.CGImage; 
CIImage *bwCIImage = [CIImage imageWithCGImage:bwCGImage]; 

CIFilter *filter = [CIFilter filterWithName:@"CIHueAdjust"]; 

// Change the float value here to change the hue 
[filter setValue:[NSNumber numberWithFloat:0.5] forKey: @"inputAngle"]; 

// input black and white image 
[filter setValue:bwCIImage forKey:kCIInputImageKey]; 

// get output from filter 
CIImage *hueImage = [filter valueForKey:kCIOutputImageKey]; 

CIContext *context = [CIContext contextWithOptions:nil]; 

CGImageRef cgImage = [context createCGImage:hueImage 
           fromRect:[hueImage extent]]; 

UIImage *coloredImage = [UIImage imageWithCGImage:cgImage]; 
CGImageRelease(cgImage); 

更多信息请参阅文档：Core Image Filter Reference