Accord.Imaging.Filters.YCbCrLinear.ProcessFilter C# (CSharp) Method

        protected override unsafe void ProcessFilter(UnmanagedImage image, Rectangle rect)
        {
            int pixelSize = Image.GetPixelFormatSize(image.PixelFormat) / 8;

            int startX = rect.Left;
            int startY = rect.Top;
            int stopX = startX + rect.Width;
            int stopY = startY + rect.Height;
            int offset = image.Stride - rect.Width * pixelSize;

            RGB rgb = new RGB();
            YCbCr ycbcr = new YCbCr();

            float ky = 0, by = 0;
            float kcb = 0, bcb = 0;
            float kcr = 0, bcr = 0;

            // Y line parameters
            if (inY.Max != inY.Min)
            {
                ky = (outY.Max - outY.Min) / (inY.Max - inY.Min);
                by = outY.Min - ky * inY.Min;
            }
            // Cb line parameters
            if (inCb.Max != inCb.Min)
            {
                kcb = (outCb.Max - outCb.Min) / (inCb.Max - inCb.Min);
                bcb = outCb.Min - kcb * inCb.Min;
            }
            // Cr line parameters
            if (inCr.Max != inCr.Min)
            {
                kcr = (outCr.Max - outCr.Min) / (inCr.Max - inCr.Min);
                bcr = outCr.Min - kcr * inCr.Min;
            }

            // do the job
            byte* ptr = (byte*)image.ImageData.ToPointer();

            // allign pointer to the first pixel to process
            ptr += (startY * image.Stride + startX * pixelSize);

            // for each row
            for (int y = startY; y < stopY; y++)
            {
                // for each pixel
                for (int x = startX; x < stopX; x++, ptr += pixelSize)
                {
                    rgb.Red = ptr[RGB.R];
                    rgb.Green = ptr[RGB.G];
                    rgb.Blue = ptr[RGB.B];

                    // convert to YCbCr
                    Accord.Imaging.YCbCr.FromRGB(rgb, ycbcr);

                    // correct Y
                    if (ycbcr.Y >= inY.Max)
                        ycbcr.Y = outY.Max;
                    else if (ycbcr.Y <= inY.Min)
                        ycbcr.Y = outY.Min;
                    else
                        ycbcr.Y = ky * ycbcr.Y + by;

                    // correct Cb
                    if (ycbcr.Cb >= inCb.Max)
                        ycbcr.Cb = outCb.Max;
                    else if (ycbcr.Cb <= inCb.Min)
                        ycbcr.Cb = outCb.Min;
                    else
                        ycbcr.Cb = kcb * ycbcr.Cb + bcb;

                    // correct Cr
                    if (ycbcr.Cr >= inCr.Max)
                        ycbcr.Cr = outCr.Max;
                    else if (ycbcr.Cr <= inCr.Min)
                        ycbcr.Cr = outCr.Min;
                    else
                        ycbcr.Cr = kcr * ycbcr.Cr + bcr;

                    // convert back to RGB
                    Accord.Imaging.YCbCr.ToRGB(ycbcr, rgb);

                    ptr[RGB.R] = rgb.Red;
                    ptr[RGB.G] = rgb.Green;
                    ptr[RGB.B] = rgb.Blue;
                }

                ptr += offset;
            }
        }
    }