#pragma mark - #pragma mark - 缩放处理 + (UIImage *)scaleImage:(UIImage *)image withScale:(float)scale { UIGraphicsBeginImageContext(CGSizeMake(image.size.width * scale, image.size.height * scale)); [image drawInRect:CGRectMake(0, 0, image.size.width * scale, image.size.height * scale)]; UIImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return scaledImage; } + (UIImage *)scaleImage:(UIImage *)image toSize:(CGSize)size { UIGraphicsBeginImageContext(CGSizeMake(size.width, size.height)); [image drawInRect:CGRectMake(0, 0, size.width, size.height)]; UIImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return scaledImage; } #pragma mark - #pragma mark - 马赛克处理 static CGContextRef CreateRGBABitmapContext (CGImageRef inImage) { CGContextRef context = NULL; CGColorSpaceRef colorSpace; void *bitmapData; //内存空间的指针,该内存空间的大小等于图像使用RGB通道所占用的字节数。 int bitmapByteCount; int bitmapBytesPerRow; size_t pixelsWide = CGImageGetWidth(inImage); //获取横向的像素点的个数 size_t pixelsHigh = CGImageGetHeight(inImage); bitmapBytesPerRow = (pixelsWide * 4); //每一行的像素点占用的字节数,每个像素点的ARGB四个通道各占8个bit(0-255)的空间 bitmapByteCount = (bitmapBytesPerRow * pixelsHigh); //计算整张图占用的字节数 colorSpace = CGColorSpaceCreateDeviceRGB();//创建依赖于设备的RGB通道 //分配足够容纳图片字节数的内存空间 bitmapData = malloc( bitmapByteCount ); //创建CoreGraphic的图形上下文,该上下文描述了bitmaData指向的内存空间需要绘制的图像的一些绘制参数 context = CGBitmapContextCreate (bitmapData, pixelsWide, pixelsHigh, 8, bitmapBytesPerRow, colorSpace, kCGImageAlphaPremultipliedLast); //Core Foundation中通过含有Create、Alloc的方法名字创建的指针,需要使用CFRelease()函数释放 CGColorSpaceRelease( colorSpace ); return context; } static unsigned char *RequestImagePixelData(UIImage *inImage) { CGImageRef img = [inImage CGImage]; CGSize size = [inImage size]; //使用上面的函数创建上下文 CGContextRef cgctx = CreateRGBABitmapContext(img); CGRect rect = {{0,0},{size.width, size.height}}; //将目标图像绘制到指定的上下文,实际为上下文内的bitmapData。 CGContextDrawImage(cgctx, rect, img); unsigned char *data = CGBitmapContextGetData (cgctx); //释放上面的函数创建的上下文 CGContextRelease(cgctx); return data; } + (UIImage *)mosaicImage:(UIImage *)image withLevel:(int)level { unsigned char *imgPixel = RequestImagePixelData(image); CGImageRef inImageRef = [image CGImage]; GLuint width = CGImageGetWidth(inImageRef); GLuint height = CGImageGetHeight(inImageRef); unsigned char prev[4] = {0}; int bytewidth = width*4; int i,j; int val = level; for(i=0;i<height;i++) { if (((i+1)%val) == 0) { memcpy(imgPixel+bytewidth*i, imgPixel+bytewidth*(i-1), bytewidth); continue; } for(j=0;j<width;j++) { if (((j+1)%val) == 1) { memcpy(prev, imgPixel+bytewidth*i+j*4, 4); continue; } memcpy(imgPixel+bytewidth*i+j*4, prev, 4); } } NSInteger dataLength = width*height* 4; //下面的代码创建要输出的图像的相关参数 CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, imgPixel, dataLength, NULL); // prep the ingredients int bitsPerComponent = 8; int bitsPerPixel = 32; CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB(); CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault; CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault; //创建要输出的图像 CGImageRef imageRef = CGImageCreate(width, height, bitsPerComponent, bitsPerPixel, bytewidth, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent); UIImage *mosaicImage = [UIImage imageWithCGImage:imageRef scale:image.scale orientation:image.imageOrientation]; CFRelease(imageRef); CGColorSpaceRelease(colorSpaceRef); CGDataProviderRelease(provider); return mosaicImage; } #define kBitsPerComponent (8) #define kBitsPerPixel (32) #define kPixelChannelCount (4) /* *转换成马赛克,level代表一个点转为多少level*level的正方形 */ + (UIImage *)transToMosaicImage:(UIImage*)orginImage blockLevel:(NSUInteger)level { //获取BitmapData CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGImageRef imgRef = orginImage.CGImage; CGFloat width = CGImageGetWidth(imgRef); CGFloat height = CGImageGetHeight(imgRef); CGContextRef context = CGBitmapContextCreate (nil, width, height, kBitsPerComponent, //每个颜色值8bit width*kPixelChannelCount, //每一行的像素点占用的字节数,每个像素点的ARGB四个通道各占8个bit colorSpace, kCGImageAlphaPremultipliedLast); CGContextDrawImage(context, CGRectMake(0, 0, width, height), imgRef); unsigned char *bitmapData = CGBitmapContextGetData (context); //这里把BitmapData进行马赛克转换,就是用一个点的颜色填充一个level*level的正方形 unsigned char pixel[kPixelChannelCount] = {0}; NSUInteger index,preIndex; for (NSUInteger i = 0; i < height - 1 ; i++) { for (NSUInteger j = 0; j < width - 1; j++) { index = i * width + j; if (i % level == 0) { if (j % level == 0) { memcpy(pixel, bitmapData + kPixelChannelCount*index, kPixelChannelCount); }else{ memcpy(bitmapData + kPixelChannelCount*index, pixel, kPixelChannelCount); } } else { preIndex = (i-1)*width +j; memcpy(bitmapData + kPixelChannelCount*index, bitmapData + kPixelChannelCount*preIndex, kPixelChannelCount); } } } NSInteger dataLength = width*height* kPixelChannelCount; CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, bitmapData, dataLength, NULL); //创建要输出的图像 CGImageRef mosaicImageRef = CGImageCreate(width, height, kBitsPerComponent, kBitsPerPixel, width*kPixelChannelCount , colorSpace, kCGImageAlphaPremultipliedLast, provider, NULL, NO, kCGRenderingIntentDefault); CGContextRef outputContext = CGBitmapContextCreate(nil, width, height, kBitsPerComponent, width*kPixelChannelCount, colorSpace, kCGImageAlphaPremultipliedLast); CGContextDrawImage(outputContext, CGRectMake(0.0f, 0.0f, width, height), mosaicImageRef); CGImageRef resultImageRef = CGBitmapContextCreateImage(outputContext); UIImage *resultImage = nil; if([UIImage respondsToSelector:@selector(imageWithCGImage:scale:orientation:)]) { // float scale = [[UIScreen mainScreen] scale]; // resultImage = [UIImage imageWithCGImage:resultImageRef scale:scale orientation:UIImageOrientationUp]; resultImage = [UIImage imageWithCGImage:resultImageRef scale:orginImage.scale orientation:orginImage.imageOrientation]; } else { resultImage = [UIImage imageWithCGImage:resultImageRef]; } //释放 if(resultImageRef){ CFRelease(resultImageRef); } if(mosaicImageRef){ CFRelease(mosaicImageRef); } if(colorSpace){ CGColorSpaceRelease(colorSpace); } if(provider){ CGDataProviderRelease(provider); } if(context){ CGContextRelease(context); } if(outputContext){ CGContextRelease(outputContext); } // return [[resultImage retain] autorelease]; return resultImage; }
时间: 2024-10-05 13:55:17