IOS CoreImage dynamic rendering (filter)

IOS CoreImage dynamic rendering (filter)

//

// ViewController. m

// CoreImageOfDong

//

// Created by Dong on 15/6/30.

// Copyright (c) 2015 xindong. All rights reserved.

//

# Import ViewController. h

# Import // Import this database

@ Interface ViewController ()

@ Property (nonatomic, strong) GLKView * glkView; // buffer view for rendering (similar to streaming media, real-time change)

@ Property (nonatomic, strong) CIFilter * filter;

@ Property (nonatomic, strong) CIImage * ciImage;

@ Property (nonatomic, strong) CIContext * ciContext;

@ End

 

@ Implementation ViewController

 

-(Void) viewDidLoad {

[Super viewDidLoad];

 

UIImage * showImage = [UIImage imageNamed: @demo1.jpg];

CGRect rect = CGRectMake (0, 0, showImage. size. width, showImage. size. height );

 

// Obtain the context of OpenGLES Rendering

EAGLContext * eagContext = [[EAGLContext alloc] initWithAPI: kEAGLRenderingAPIOpenGLES2];

 

// Create the rendered buffer

Self. glkView = [[GLKView alloc] initWithFrame: rect context: eagContext];

[Self. glkView bindDrawable]; // bind the drawing; otherwise, the screen is black at the beginning.

[Self. view addSubview: self. glkView];

 

// Create the context for CoreImage

Self. ciContext = [CIContext contextWithEAGLContext: eagContext options :@{ kCIContextWorkingColorSpace: [NSNull null]}];

 

// CoreImage settings

Self. ciImage = [[CIImage alloc] initWithImage: showImage];

Self. filter = [CIFilter filterWithName: @ CISepiaTone];

[Self. filter setValue: self. ciImage forKey: kCIInputImageKey];

[Self. filter setValue: @ (0) forKey: kCIInputIntensityKey];

 

// Start Rendering

[Self. ciContext drawImage: [self. filter valueForKey: kCIOutputImageKey] inRect: CGRectMake (0, 0, self. glkView. drawableWidth, self. glkView. drawableHeight) fromRect: [self. ciImage extent];

[Self. glkView display];

 

// Dynamic Rendering

UISlider * slider = [[UISlider alloc] initWithFrame: CGRectMake (30,500,200, 10)];

Slider. minimumValue = 0.f;

Slider. maximumValue = 10.f;

[Slider addTarget: self action: @ selector (changeColorValue :) forControlEvents: UIControlEventValueChanged];

[Self. view addSubview: slider];

}

-(Void) changeColorValue :( UISlider *) slider

{

[Self. filter setValue: self. ciImage forKey: kCIInputImageKey];

[Self. filter setValue: @ (slider. value) forKey: kCIInputIntensityKey];

// Start Rendering

[Self. ciContext drawImage: [self. filter valueForKey: kCIOutputImageKey] inRect: CGRectMake (0, 0, self. glkView. drawableWidth, self. glkView. drawableHeight) fromRect: [self. ciImage extent];

[Self. glkView display];

}