CIImageとofImageの変換の練習

gistfile1.m

// CIImageとofImageのコンバートの練習 ===================

void saveCIImage(CIImage *ciImage) {
    NSBitmapImageRep* rep = [[NSBitmapImageRep alloc]
                             initWithCIImage:ciImage];
    NSData* PNGData = [rep representationUsingType:NSPNGFileType
                                        properties:nil];
    NSString *filepath = [NSString stringWithCString:ofToDataPath(ofGetTimestampString() + ".png").c_str() encoding:NSUTF8StringEncoding];
    [PNGData writeToFile:filepath  atomically:NO];
}

void convertTest(ofImage &src, ofImage &dst) {
    // ofImage -> CIImage
    unsigned char *pixels = src.getPixels();
    NSBitmapImageRep *rep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:&pixels pixelsWide:src.width pixelsHigh:src.height bitsPerSample:8 samplesPerPixel:3 hasAlpha:NO isPlanar:NO colorSpaceName:NSDeviceRGBColorSpace bitmapFormat:NSAlphaNonpremultipliedBitmapFormat bytesPerRow:3*src.width bitsPerPixel:24];
    CIImage *ciImage = [[CIImage alloc] initWithBitmapImageRep:rep];
    saveCIImage(ciImage);
    
    // CIImage -> ofImage
    CIContext *ciContext = [[CIContext alloc] init];
    CGImageRef cgimg = [ciContext createCGImage:ciImage fromRect:[ciImage extent]];
    
    NSUInteger width = CGImageGetWidth(cgimg);
    NSUInteger height = CGImageGetHeight(cgimg);
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    dst.setImageType(OF_IMAGE_COLOR_ALPHA); // なんか4チャンネルになっちゃうみたい
    unsigned char *rawData = dst.getPixels();//(unsigned char*)calloc(height*width*4, sizeof(unsigned char));
    NSUInteger bpp = 4;
    NSUInteger bpr = bpp * width;
    NSUInteger bpc = 8;
    CGContextRef cgContext = CGBitmapContextCreate(rawData, width, height, bpc, bpr, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
    CGColorSpaceRelease(colorSpace);
    
    CGContextDrawImage(cgContext, CGRectMake(0, 0, width, height), cgimg);
    CGContextRelease(cgContext);
    
    CGImageRelease(cgimg);
    
    dst.update();
}