ios - 在iOS中移动滑块时如何在图像上应用亮度，对比度， Gamma ？

嗨，我正在使用GPUImagefilters在图像上应用亮度。但是它不起作用。我在哪里都找不到这个问题。我的代码是这样的

- (void)viewDidLoad
{
self.slider.hidden=YES;
slider.minimumValue = 0.0;
slider.maximumValue = 1.0;
slider.value = 0.1;
}
- (IBAction)brightnessClicked:(id)sender
{
self.slider.hidden=NO;

}
- (IBAction)sliderMoved:(id)sender
{

image_p=[[GPUImagePicture alloc]initWithImage:image3];

GPUImageBrightnessFilter *filter1 = [[GPUImageBrightnessFilter alloc] init];

[image_p addTarget:filter1];

[image_p processImage];
[(GPUImageBrightnessFilter *)filter setBrightness:[(UISlider *)sender value]];

//    UIImageWriteToSavedPhotosAlbum([filter1 imageFromCurrentlyProcessedOutput], self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

//self.thirdImgView.image = [image3 brightness:(1+value-0.5)];
//    self.thirdImgView.image = ;

}

如果无法让GPUImagefilters告诉我任何其他方式。我尝试了更多方式，但是它不起作用，所以请任何人建议我该怎么做。

最佳答案

试试这些

-(void)viewDidLoad
{
   [sliderChange setMinimumValue:-0.5];

   [sliderChange setMaximumValue:0.5];

   [sliderChange setValue:0.0];

   brightnessFilter = [[GPUImageBrightnessFilter alloc] init];

}

-(IBAction)upDateSliderValue:(id)sender
{

   GPUImagePicture *fx_image;

   fx_image = [[GPUImagePicture alloc] initWithImage:originalImage];

   [brightnessFilter setBrightness:self.sliderChange.value];

   [fx_image addTarget:brightnessFilter];

   [fx_image processImage];

   UIImage *final_image = [brightnessFilter imageFromCurrentlyProcessedOutput];

   self.selectedImageView.image = final_image;

}