如果我尝试测试这段代码，我的UIImage是零：
- (IBAction)sliderBrightness:(id)sender {
UIImage *inputImage = imgView.image;
GPUImageBrightnessFilter *stillImageFilter = [[GPUImageBrightnessFilter alloc] init];
GPUImagePicture *stillImageSource = [[GPUImagePicture alloc] initWithImage:inputImage];
[stillImageSource addTarget:stillImageFilter];
[stillImageFilter useNextFrameForImageCapture];
[stillImageSource processImage];
UIImage *currentFilteredVideoFrame = [stillImageFilter imageFromCurrentFramebuffer];
[self->imgView setImage:currentFilteredVideoFrame];
}
UPDATE:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
imgView.image = [info objectForKey:@"UIImagePickerControllerEditedImage"];
if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
toolbar.hidden = NO;
UIImage *image1 = imgView.image;
NSString *cachedFolderPath = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)[0];
NSString *cachedImagePath = [cachedFolderPath stringByAppendingPathComponent:@"image1.png"];
[UIImagePNGRepresentation(image1) writeToFile:cachedImagePath atomically:YES];
}
if (picker.sourceType == UIImagePickerControllerSourceTypePhotoLibrary) {
toolbar.hidden = NO;
UIImage *image1 = imgView.image;
NSString *cachedFolderPath = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)[0];
NSString *cachedImagePath = [cachedFolderPath stringByAppendingPathComponent:@"image1.png"];
[UIImagePNGRepresentation(image1) writeToFile:cachedImagePath atomically:YES];
}
if (picker.sourceType == UIImagePickerControllerSourceTypeSavedPhotosAlbum) {
toolbar.hidden = NO;
UIImage *image1 = imgView.image;
NSString *cachedFolderPath = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)[0];
NSString *cachedImagePath = [cachedFolderPath stringByAppendingPathComponent:@"image1.png"];
[UIImagePNGRepresentation(image1) writeToFile:cachedImagePath atomically:YES];
}
else{
toolbar.hidden = NO;
}
[self dismissViewControllerAnimated:YES completion:nil];
}
调试器（inputImage为nil）：
我希望有一个人可以帮助我 . 在此先感谢您的帮助 .
我正在使用xcode 5.1.1（iOS模拟器：iPhone 4英寸; 64位; iOS7.1）
1 回答
如果（正如您在评论中所述）问题是
inputImage为零，则问题是您发布的代码的外部问题 . 要么imgView本身为零，要么它指向尚未设置其图像的UIImageView实例 . 在线上放一个断点：并检查
imgView以确定哪些可能性是问题所在 .