BitMiracle.LibTiff.Classic.TiffRgbaImage.put4bitcmaptile C# (CSharp) Method

        private static void put4bitcmaptile(
            TiffRgbaImage img, int[] raster, int rasterOffset, int rasterShift,
            int x, int y, int width, int height, byte[] buffer, int offset, int bufferShift)
        {
            int[][] PALmap = img.PALmap;
            bufferShift /= 2;

            while (height-- > 0)
            {
                int[] bw = null;

                int _x;
                for (_x = width; _x >= 2; _x -= 2)
                {
                    bw = PALmap[buffer[offset]];
                    offset++;
                    for (int rc = 0; rc < 2; rc++)
                    {
                        raster[rasterOffset] = bw[rc];
                        rasterOffset++;
                    }
                }

                if (_x != 0)
                {
                    bw = PALmap[buffer[offset]];
                    offset++;

                    raster[rasterOffset] = bw[0];
                    rasterOffset++;
                }

                rasterOffset += rasterShift;
                offset += bufferShift;
            }
        }