How to change the skin color of face from the source image in ios?

MY code: How to manage RGB value for differet shades of face,and how to apply? this code will change the color of face along with hair,but i want 1.only face to be colored excluding hair.

    -(void)changeSkinColorValue:(float)value WithImage:(UIImage*)needToModified
    {

        CGContextRef ctx;

        CGImageRef imageRef = needToModified.CGImage;
        NSUInteger width = CGImageGetWidth(imageRef);
        NSUInteger height = CGImageGetHeight(imageRef);
        CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
        //unsigned char *rawData = malloc(firstImageV.image.size.height * firstImageV.image.size.width * 10);

        CFMutableDataRef m_DataRef = CFDataCreateMutableCopy(0, 0,CGDataProviderCopyData(CGImageGetDataProvider(firstImageV.image.CGImage)));
        UInt8 *rawData = (UInt8 *) CFDataGetMutableBytePtr(m_DataRef);
        int length = CFDataGetLength(m_DataRef);
        NSUInteger bytesPerPixel = 4;
        NSUInteger bytesPerRow = bytesPerPixel * firstImageV.image.size.width;
        NSUInteger bitsPerComponent = 8;

                CGContextRef context1 = CGBitmapContextCreate(rawData, firstImageV.image.size.width, firstImageV.image.size.height, bitsPerComponent, bytesPerRow, colorSpace,                     kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
        CGColorSpaceRelease(colorSpace);

        CGContextDrawImage(context1, CGRectMake(0, 0, firstImageV.image.size.width, firstImageV.image.size.height), imageRef);

        NSLog(@"%d::%d",width,height);


       // for(int ii = 0 ; ii < 250   ; ii+=4)
        //{

            for(int ii = 0 ; ii < length ; ii+=4)
            {
            //NSLog(@"Raw data %s",rawData);

            int  R = rawData[ii];
            int G = rawData[ii+1];
            int B = rawData[ii+2];

            //        NSLog(@"%d   %d   %d", R, G, B);
            //if( ( (R>60)&&(R<237) ) || ((G>10)&&(G<120))||((B>4) && (B&l

CFDataGetBytePtr According to the docs, it Returns a read-only pointer to the bytes of a CFData object., are you sure you're not looking for CFDataGetBytes which Copies the byte contents of a CFData object to an external buffer. In which case you'll have to allocate your buffer to contain width * height * bpp. Once you have this copy, you can manipulate it anyway you want to create the new picture.

Pixel Selection According to your question, I seem to understand that you want to change skin color from White to Black. Your current code iterates over every pixel to change its color. You should evaluate the "distance" between the pixel color and what you're looking for, and if it's below a certain threshold process it. It might be easier to perform the operation in HSV than by dealing with RGB colors

answered 2013-07-30T19:04:29.167

How to change the skin color of face from the source image in ios?

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