GPUImage使用几点总结
1.使用相机观察滤镜实时效果：
首先定义以下属性
@property (nonatomic, strong) GPUImageStillCamera* Camera;//相机
@property (nonatomic, strong) GPUImageView*GPUImgView;//拍照视图
@property (nonatomic, strong) GPUImageOutput<GPUImageInput>*Filter;//滤镜
在 viewdidlod中这样写_Camera = [[GPUImageStillCamera alloc]initWithSessionPreset:AVCaptureSessionPreset640x480 cameraPosition:AVCaptureDevicePositionBack];
_Camera.outputImageOrientation = UIInterfaceOrientationPortrait;
_GPUImgView = [[GPUImageView alloc]initWithFrame:CGRectMake(0, 64, self.view.bounds.size.width, self.view.bounds.size.width)];
_Filter = [[GPUImageHueFilter alloc] init];//你还可以更换其他滤镜如_Filter = [[GPUImageSketchFilter alloc] init];
[_Camera addTarget:_Filter];
[_Filter addTarget:_GPUImgView];
[self.view addSubview:_GPUImgView];
[_Camera startCameraCapture];
当你准备用collectionVIew来实现选择滤镜种类时 在collectionview代理中这样写-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
[_Camera removeAllTargets];
switch (indexPath.item) {
case 0: {
_Filter = [[GPUImageStretchDistortionFilter alloc]init];
}break;
case 1:
{
_Filter = [[GPUImageFilter alloc] initWithFragmentShaderFromFile:@"CustomFilter"];
}break;
case 2:{
_Filter = [[GPUImageSepiaFilter alloc] init];
}
break;
case 3:{
_Filter = [[GPUImageRGBClosingFilter alloc] initWithRadius:4];
}break;
case 4:{
_Filter = [[GPUImageGlassSphereFilter alloc] init];
[(GPUImageGlassSphereFilter *)_Filter setRadius:0.5];
GPUImageGaussianBlurFilter *gaussianBlur = [[GPUImageGaussianBlurFilter alloc] init];
[_Camera addTarget:gaussianBlur];
gaussianBlur.blurRadiusInPixels = 5.0;
GPUImageAlphaBlendFilter *blendFilter = [[GPUImageAlphaBlendFilter alloc] init];
blendFilter.mix = 1.0;
[gaussianBlur addTarget:blendFilter];
[_Filter addTarget:blendFilter];
[blendFilter addTarget:_mGPUImgView];
}break;
case 5:{
_Filter = [[GPUImageSoftEleganceFilter alloc] init];
}break;
case 6:{
_Filter = [[GPUImageMissEtikateFilter alloc] init];
}break;
case 7:{
_Filter = [[GPUImageAmatorkaFilter alloc] init];
}break;
case 8:{
_Filter = [[GPUImagePinchDistortionFilter alloc] init];
}break;
case 9:{
_Filter = [[GPUImageSwirlFilter alloc] init];
}break;
case 10:{
_Filter = [[GPUImageColorInvertFilter alloc] init];
}break;
case 11:{
_Filter = [[GPUImageSketchFilter alloc] init];
[(GPUImageSketchFilter *)_Filter setEdgeStrength:0.45];
}break;
default:
break;
}
[_Camera addTarget:_Filter];
[_Filter addTarget:_GPUImgView];
}
如果你要拍照请调用以下方法
-(void)takePhoto{
[_Camera capturePhotoAsJPEGProcessedUpToFilter:_Filter withCompletionHandler:^(NSData *processedJPEG, NSError *error){
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library writeImageDataToSavedPhotosAlbum:processedJPEG metadata:_mCamera.currentCaptureMetadata completionBlock:^(NSURL *assetURL, NSError *error2)
{
if (error2) {
NSLog(@"ERROR: the image failed to be written");
}
else {
NSLog(@"PHOTO SAVED - assetURL: %@", assetURL);
}
}];
}];
}
2.直接用滤镜美化图片：
_Filter = [[GPUImageFilter alloc] initWithFragmentShaderFromFile:@"CustomFilter"];
[_Filter forceProcessingAtSize:_photoImageview.frame.size];//设置渲染尺寸
[_Filter useNextFrameForImageCapture];
GPUImagePicture* stillImageSource = [[GPUImagePicture alloc]initWithImage:[UIImage imageNamed:@"IMGTEST.jpg"]];
[stillImageSource addTarget:_Filter];
[stillImageSource processImage];//渲染
UIImage*newImage = [_Filter imageFromCurrentFramebuffer];//得到渲染后图片
_photoImageview.image = newImage;