CoreImage 处理图片

标签：ios   coreimage 处理图片   

1.CoreImage 滤镜的使用(马赛克模糊)

- (void)hFilter {

    // 0. 导入CIImage图片

    CIImage *ciImage = [[CIImage alloc] initWithImage:[UIImage imageNamed:@"demo"]];

    // 1. 创建出Filter滤镜

    CIFilter *filter = [CIFilter filterWithName:@"CIPixellate"];

    [filter setValue:ciImage

              forKey:kCIInputImageKey];

    NSLog(@"%@", filter.attributes);

    [filter setDefaults];

    CIImage *outImage = [filter valueForKey:kCIOutputImageKey];

    // 2. 用CIContext将滤镜中的图片渲染出来

    CIContext *context = [CIContext contextWithOptions:nil];

    CGImageRef cgImage = [context createCGImage:outImage

                                       fromRect:[outImage extent]];

    // 3. 导出图片

    UIImage *showImage = [UIImage imageWithCGImage:cgImage];

    CGImageRelease(cgImage);

    // 4. 加载出来

    UIImageView *imageView = [[UIImageView alloc] initWithImage:showImage];

    imageView.center       = self.view.center;

    [self.view addSubview:imageView];

}

2.CoreImage 滤镜的组合

- (void)complexCoreImage {

    // 0. 导入CIImage图片

    CIImage *ciImage = [[CIImage alloc] initWithImage:[UIImage imageNamed:@"demo"]];

    // 1. 创建出Filter滤镜

    CIFilter *filterOne = [CIFilter filterWithName:@"CIPixellate"];

    [filterOne setValue:ciImage

              forKey:kCIInputImageKey];

    [filterOne setDefaults];

    CIImage *outImage = [filterOne valueForKey:kCIOutputImageKey];

    CIFilter *filterTwo = [CIFilter filterWithName:@"CIHueAdjust"];

    [filterTwo setValue:outImage

                 forKey:kCIInputImageKey];

    [filterTwo setDefaults];

    //默认为0,不设置不能改变，可以封装一个调用

    [filterTwo setValue:@(3.14)

                 forKey:kCIInputAngleKey];

    NSLog(@"%@",filterTwo.attributes);//可以看到一些参数 key

    CIImage *outputImage = [filterTwo valueForKey:kCIOutputImageKey];

    // 2. 用CIContext将滤镜中的图片渲染出来

    CIContext *context = [CIContext contextWithOptions:nil];

    CGImageRef cgImage = [context createCGImage:outputImage

                                       fromRect:[outImage extent]];

    // 3. 导出图片

    UIImage *showImage = [UIImage imageWithCGImage:cgImage];

    CGImageRelease(cgImage);

    // 4. 加载出来

    UIImageView *imageView = [[UIImageView alloc] initWithImage:showImage];

    imageView.center       = self.view.center;

    [self.view addSubview:imageView];

}

3.在 OpenGLES 下进行渲染

#import <GLKit/GLKit.h>

@interface ViewController ()

@property (nonatomic, strong) GLKView   *glkView; // 渲染用的buffer视图

@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:@"demo"];

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

    // 获取OpenGLES渲染的上下文

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

    // 创建出渲染的buffer

    _glkView = [[GLKView alloc] initWithFrame:rect

                                      context:eagContext];

    [_glkView bindDrawable];

    [self.view addSubview:_glkView];

    // 创建出CoreImage用的上下文

    _ciContext = [CIContext contextWithEAGLContext:eagContext

                                           options:@{kCIContextWorkingColorSpace : [NSNull null]}];

    // CoreImage相关设置

    _ciImage = [[CIImage alloc] initWithImage:showImage];

    _filter = [CIFilter filterWithName:@"CISepiaTone"];

    [_filter setValue:_ciImage forKey:kCIInputImageKey];

    [_filter setValue:@(0) forKey:kCIInputIntensityKey];

    // 开始渲染

    [_ciContext drawImage:[_filter outputImage]

                   inRect:CGRectMake(0, 0, _glkView.drawableWidth, _glkView.drawableHeight)

                 fromRect:[_ciImage extent]];

    [_glkView display];

    // 动态渲染

    UISlider *slider    = [[UISlider alloc] initWithFrame:CGRectMake(0, 400, 320, 20)];

    slider.minimumValue = 0.f;

    slider.maximumValue = 1.f;

    [slider addTarget:self action:@selector(sliderEvent:) forControlEvents:UIControlEventValueChanged];

    [self.view addSubview:slider];

}

- (void)sliderEvent:(UISlider *)slider {

    [_filter setValue:_ciImage forKey:kCIInputImageKey];

    [_filter setValue:@(slider.value)

               forKey:kCIInputIntensityKey];

    // 开始渲染

    [_ciContext drawImage:[_filter outputImage]

                   inRect:CGRectMake(0, 0, _glkView.drawableWidth, _glkView.drawableHeight)

                 fromRect:[_ciImage extent]];

    [_glkView display];

}

CoreImage 处理图片

标签：ios   coreimage 处理图片   

原文地址：http://blog.csdn.net/baitxaps/article/details/46918793