使用CoreImage教程
CoreImage包含有很多实用的滤镜,专业处理图片的库,为了能看到各种渲染效果,请使用如下图片素材.
现在可以开始教程了:
#define FIX_IMAGE(image) fixImageWidth(image, 320.f)
// 固定图片的宽度
UIImage * fixImageWidth(UIImage *image, CGFloat width)
{
float newHeight = image.size.height * (width / image.size.width);
CGSize size = CGSizeMake(width, newHeight);
UIGraphicsBeginImageContextWithOptions(size, NO, 0);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, 0.0, size.height);
CGContextScaleCTM(context, 1.0, -1.0);
CGContextSetBlendMode(context, kCGBlendModeCopy);
CGContextDrawImage(context, CGRectMake(0.0f, 0.0f, size.width, size.height),
image.CGImage);
UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageOut;
}
代码片段
// 将UIImage转换成CIImage
CIImage *ciImage = [[CIImage alloc] initWithImage:[UIImage imageNamed:@"1.jpg"]];
// 创建滤镜
CIFilter *filter = [CIFilter filterWithName:@"CIPhotoEffectMono"
keysAndValues:kCIInputImageKey, ciImage, nil];
[filter setDefaults];
// 获取绘制上下文
CIContext *context = [CIContext contextWithOptions:nil];
// 渲染并输出CIImage
CIImage *outputImage = [filter outputImage];
// 创建CGImage句柄
CGImageRef cgImage = [context createCGImage:outputImage
fromRect:[outputImage extent]];
// 获取图片
UIImage *showImage = [UIImage imageWithCGImage:cgImage];
// 释放CGImage句柄
CGImageRelease(cgImage);
// 显示图片
UIImageView *imageView = \
[[UIImageView alloc] initWithImage:FIX_IMAGE(showImage)];
[self.view addSubview:imageView];
代码片段
效果如下:
我们对操作进行简易的封装:
CIFilterEffect.h + CIFilterEffect.m
//
// CIFilterEffect.h
// CIFilter
//
// Created by YouXianMing on 14-5-9.
// Copyright (c) 2014年 Y.X. All rights reserved.
//
#import <Foundation/Foundation.h>
@interface CIFilterEffect : NSObject
@property (nonatomic, strong, readonly) UIImage *result;
- (instancetype)initWithImage:(UIImage *)image filterName:(NSString *)name;
@end//
// CIFilterEffect.m
// CIFilter
//
// Created by YouXianMing on 14-5-9.
// Copyright (c) 2014年 Y.X. All rights reserved.
//
#import "CIFilterEffect.h"
@interface CIFilterEffect ()
@property (nonatomic, strong, readwrite) UIImage *result;
@end
@implementation CIFilterEffect
- (instancetype)initWithImage:(UIImage *)image filterName:(NSString *)name
{
self = [super init];
if (self)
{
// 将UIImage转换成CIImage
CIImage *ciImage = [[CIImage alloc] initWithImage:image];
// 创建滤镜
CIFilter *filter = [CIFilter filterWithName:name
keysAndValues:kCIInputImageKey, ciImage, nil];
[filter setDefaults];
// 获取绘制上下文
CIContext *context = [CIContext contextWithOptions:nil];
// 渲染并输出CIImage
CIImage *outputImage = [filter outputImage];
// 创建CGImage句柄
CGImageRef cgImage = [context createCGImage:outputImage
fromRect:[outputImage extent]];
_result = [UIImage imageWithCGImage:cgImage];
// 释放CGImage句柄
CGImageRelease(cgImage);
}
return self;
}
@end我们来开始尝试其他的滤镜效果,我们可以尝试的至少有这些:
@"CILinearToSRGBToneCurve",
@"CIPhotoEffectChrome",
@"CIPhotoEffectFade",
@"CIPhotoEffectInstant",
@"CIPhotoEffectMono",
@"CIPhotoEffectNoir",
@"CIPhotoEffectProcess",
@"CIPhotoEffectTonal",
@"CIPhotoEffectTransfer",
@"CISRGBToneCurveToLinear",
@"CIVignetteEffect",
下面是所有渲染出来的图片,与上面提供的滤镜名字一一对应:
以下效果是需要进行一些配置才能达到的效果,这个就不开源了,你懂得:).
福利:
Core Image Filter Reference
CICategoryBlur
CICategoryColorAdjustment
CIColorClampCIColorControlsCIColorMatrixCIColorPolynomialCIExposureAdjustCIGammaAdjustCIHueAdjustCILinearToSRGBToneCurveCISRGBToneCurveToLinearCITemperatureAndTintCIToneCurveCIVibranceCIWhitePointAdjust
CICategoryColorEffect(我们刚刚用到的一些效果在这里哦)
CIColorCrossPolynomialCIColorCubeCIColorCubeWithColorSpaceCIColorInvertCIColorMapCIColorMonochromeCIColorPosterizeCIFalseColorCIMaskToAlphaCIMaximumComponentCIMinimumComponentCIPhotoEffectChromeCIPhotoEffectFadeCIPhotoEffectInstantCIPhotoEffectMonoCIPhotoEffectNoirCIPhotoEffectProcessCIPhotoEffectTonalCIPhotoEffectTransferCISepiaToneCIVignetteCIVignetteEffect
CICategoryCompositeOperation
CIAdditionCompositingCIColorBlendModeCIColorBurnBlendModeCIColorDodgeBlendModeCIDarkenBlendModeCIDifferenceBlendModeCIExclusionBlendModeCIHardLightBlendModeCIHueBlendModeCILightenBlendModeCILuminosityBlendModeCIMaximumCompositingCIMinimumCompositingCIMultiplyBlendModeCIMultiplyCompositingCIOverlayBlendModeCISaturationBlendModeCIScreenBlendModeCISoftLightBlendModeCISourceAtopCompositingCISourceInCompositingCISourceOutCompositingCISourceOverCompositing
CICategoryDistortionEffect
CIBumpDistortionCIBumpDistortionLinearCICircleSplashDistortionCICircularWrapCIDrosteCIDisplacementDistortionCIGlassDistortionCIGlassLozengeCIHoleDistortionCILightTunnelCIPinchDistortionCIStretchCropCITorusLensDistortionCITwirlDistortionCIVortexDistortion
CICategoryGenerator
CICheckerboardGeneratorCIConstantColorGeneratorCILenticularHaloGeneratorCIQRCodeGeneratorCIRandomGeneratorCIStarShineGeneratorCIStripesGeneratorCISunbeamsGenerator
CICategoryGeometryAdjustment
CIAffineTransformCICropCILanczosScaleTransformCIPerspectiveTransformCIPerspectiveTransformWithExtentCIStraightenFilter
CICategoryGradient
CICategoryHalftoneEffect
CICategoryReduction
CIAreaAverageCIAreaHistogramCIRowAverageCIColumnAverageCIHistogramDisplayFilterCIAreaMaximumCIAreaMinimumCIAreaMaximumAlphaCIAreaMinimumAlpha
CICategorySharpen
CICategoryStylize
CIBlendWithAlphaMaskCIBlendWithMaskCIBloomCIComicEffectCIConvolution3X3CIConvolution5X5CIConvolution7X7CIConvolution9HorizontalCIConvolution9VerticalCICrystallizeCIDepthOfFieldCIEdgesCIEdgeWorkCIGloomCIHeightFieldFromMaskCIHexagonalPixellateCIHighlightShadowAdjustCILineOverlayCIPixellateCIPointillizeCIShadedMaterialCISpotColorCISpotLight
CICategoryTileEffect
CIAffineClampCIAffineTileCIEightfoldReflectedTileCIFourfoldReflectedTileCIFourfoldRotatedTileCIFourfoldTranslatedTileCIGlideReflectedTileCIKaleidoscopeCIOpTileCIParallelogramTileCIPerspectiveTileCISixfoldReflectedTileCISixfoldRotatedTileCITriangleKaleidoscopeCITriangleTileCITwelvefoldReflectedTile
CICategoryTransition
CIBarsSwipeTransitionCICopyMachineTransitionCIDisintegrateWithMaskTransitionCIDissolveTransitionCIFlashTransitionCIModTransitionCIPageCurlTransitionCIPageCurlWithShadowTransitionCIRippleTransitionCISwipeTransition
时间： 2024-10-22 05:11:57