我正在尝试使用 Core Image 处理图像。我已经创建了 UIImage 类别来做到这一点。
我已经将 QuartzCore 和 CoreImage 框架添加到项目中,导入了 CoreImage/CoreImage.h 并使用了以下代码:
CIImage *inputImage = self.CIImage;
CIFilter *exposureAdjustmentFilter = [CIFilter filterWithName:@"CIExposureAdjust"];
[exposureAdjustmentFilter setDefaults];
[exposureAdjustmentFilter setValue:inputImage forKey:@"inputImage"];
[exposureAdjustmentFilter setValue:[NSNumber numberWithFloat:5.0f] forKey:@"inputEV"];
CIImage *outputImage = [exposureAdjustmentFilter valueForKey:@"outputImage"];
CIContext *myContext = [CIContext contextWithOptions:nil];
return [UIImage imageWithCGImage:[myContext createCGImage:outputImage fromRect:outputImage.extent]];
但我从过滤器中得到了nil输出图像。
我也尝试使用 CIHueAdjust 得到相同的结果。
比你提前
更新:我找到了解决方案。有必要分配新的 CIImage,而不仅仅是通过这种方式传递对 UIImage.CIImage 的引用:
CIImage *inputImage = [[CIImage alloc] initWithImage:self];
最佳答案
尝试以下代码:-
CIImage *inputImage = [[CIImage alloc] initWithImage:[UIImage imageNamed:@"old-country-rain.jpg"]];
CIFilter * controlsFilter = [CIFilter filterWithName:@"CIExposureAdjust"];
[controlsFilter setValue:inputImage forKey:kCIInputImageKey];
[controlsFilter setValue:[NSNumber numberWithFloat: 2.0f] forKey:@"inputEV"];
NSLog(@"%@",controlsFilter.attributes);
CIImage *displayImage = controlsFilter.outputImage;
UIImage *finalImage = [UIImage imageWithCIImage:displayImage];
CIContext *context = [CIContext contextWithOptions:nil];
if (displayImage == nil || finalImage == nil) {
// We did not get output image. Let's display the original image itself.
imageView.image = [UIImage imageNamed:@"old-country-rain.jpg"];
}else {
// We got output image. Display it.
imageView.image = [UIImage imageWithCGImage:[context createCGImage:displayImage fromRect:displayImage.extent]];
}
关于iphone - iOS - 无法使用 CIFilter 处理图像,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/8519302/