我目前正在尝试使用 GPUImage 显示直方图。我目前有以下代码:
GPUImageOutput<GPUImageInput> *filter = [[GPUImageHistogramFilter alloc] initWithHistogramType:kGPUImageHistogramLuminance];
[self.stillCamera removeTarget:filter];
GPUImageGammaFilter *gammaFilter = [[GPUImageGammaFilter alloc] init];
[self.stillCamera addTarget:gammaFilter];
[gammaFilter addTarget:filter];
GPUImageHistogramGenerator *histogramGraph = [[GPUImageHistogramGenerator alloc] init];
[histogramGraph forceProcessingAtSize:CGSizeMake(500.0, 500)];
[filter addTarget:histogramGraph];
GPUImageAlphaBlendFilter *blendFilter = [[GPUImageAlphaBlendFilter alloc] init];
blendFilter.mix = 0.75;
[blendFilter forceProcessingAtSize:CGSizeMake(500, 500)];
[self.stillCamera addTarget:blendFilter];
[histogramGraph addTarget:blendFilter];
[blendFilter addTarget:previewView];
上面显示了在我的预览 View 上过度显示的直方图。 (但是它确实会闪烁,另一个问题,改天)
我想在 View 上特定位置的较小 View 上显示此直方图。我怎样才能做到这一点?
最佳答案
要在单独的 View 中显示直方图,您需要在主视图中添加另一个 GPUImageView
并将直方图过滤器指向它。以下是基于 SimpleImageFilter
示例的源代码。
- (void)loadView
{
CGRect mainScreenFrame = [[UIScreen mainScreen] applicationFrame];
GPUImageView *primaryView = [[GPUImageView alloc] initWithFrame:mainScreenFrame];
self.view = primaryView;
UIImage *inputImage = [UIImage imageNamed:@"WID-small.jpg"];
GPUImagePicture *sourcePicture = [[GPUImagePicture alloc] initWithImage:inputImage smoothlyScaleOutput:YES];
// Creating another view to show histogram
GPUImageView *histView = [[GPUImageView alloc] initWithFrame:CGRectMake(mainScreenFrame.size.width - 100, mainScreenFrame.size.height - 100, 100, 100)];
[primaryView addSubview:histView];
// Create histogram filter and generator and point it to histogram view
GPUImageOutput<GPUImageInput> *histFilter = [[GPUImageHistogramFilter alloc] initWithHistogramType:kGPUImageHistogramLuminance];
GPUImageOutput<GPUImageInput> *histGenerator = [[GPUImageHistogramGenerator alloc] init];
[histGenerator forceProcessingAtSize:histView.sizeInPixels];
[sourcePicture addTarget:histFilter];
[histFilter addTarget:histGenerator];
// Note target - hist view
[histGenerator addTarget:histView];
// Setup sepia filter just to show main picture
GPUImageOutput<GPUImageInput> *sepiaFilter = [[GPUImageSepiaFilter alloc] init];
[sepiaFilter forceProcessingAtSize:primaryView.sizeInPixels];
[sourcePicture addTarget:sepiaFilter];
// Note target - main view
[sepiaFilter addTarget:primaryView];
[sourcePicture processImage];
}
最终结果:
关于ios - GPUImage 在另一个 View 中显示直方图,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/29870565/