예제 #1
0
        public static unsafe void ToRgb24(Lab24* from, Rgb24* to, int length=1)
        {
            if (length < 1) return;

            // 使用 OpenCV 中的算法实现
            const float coeff0 = 0.39215686274509809f;
            const float coeff1 = 0.0f;
            const float coeff2 = 1.0f;
            const float coeff3 = (-128.0f);
            const float coeff4 = 1.0f;
            const float coeff5 = (-128.0f);

            Lab24* end = from + length;
            float x, y, z,l,a,b;
            int blue, green, red;

            while (from != end)
            {
                l = from->L * coeff0 + coeff1;
                a = from->A * coeff2 + coeff3;
                b = from->B * coeff4 + coeff5;

                l = (l + labLShift_32f) * (1.0f / labLScale_32f);
                x = (l + a * 0.002f);
                z = (l - b * 0.005f);

                y = l * l * l;
                x = x * x * x;
                z = z * z * z;

                blue = (int)((x * labBx_32f + y * labBy_32f + z * labBz_32f) * 255 + 0.5);
                green = (int)((x * labGx_32f + y * labGy_32f + z * labGz_32f) * 255 + 0.5);
                red = (int)((x * labRx_32f + y * labRy_32f + z * labRz_32f) * 255 + 0.5);

                red = red < 0 ? 0 : red > 255 ? 255 : red;
                green = green < 0 ? 0 : green > 255 ? 255 : green;
                blue = blue < 0 ? 0 : blue > 255 ? 255 : blue;

                to->Red = (byte)red;
                to->Green = (byte)green;
                to->Blue = (byte)blue;

                from++;
                to++;
            }
        }
예제 #2
0
        public static unsafe void ToLab24(Byte* from, Lab24* to, int length = 1)
        {
            // 使用 OpenCV 中的算法实现

            if (length < 1) return;

            Byte* end = from + length;

            int x, y, z;
            int l, a, b;
            bool flag;

            while (from != end)
            {
                Byte val = *from;
                Byte red = val;
                Byte green = val;
                Byte blue = val;

                x = blue * labXb + green * labXg + red * labXr;
                y = blue * labYb + green * labYg + red * labYr;
                z = blue * labZb + green * labZg + red * labZr;

                flag = x > labT;

                x = (((x) + (1 << ((lab_shift) - 1))) >> (lab_shift));

                if (flag)
                    x = icvLabCubeRootTab[x];
                else
                    x = (((x * labSmallScale + labSmallShift) + (1 << ((lab_shift) - 1))) >> (lab_shift));

                flag = z > labT;
                z = (((z) + (1 << ((lab_shift) - 1))) >> (lab_shift));

                if (flag == true)
                    z = icvLabCubeRootTab[z];
                else
                    z = (((z * labSmallScale + labSmallShift) + (1 << ((lab_shift) - 1))) >> (lab_shift));

                flag = y > labT;
                y = (((y) + (1 << ((lab_shift) - 1))) >> (lab_shift));

                if (flag == true)
                {
                    y = icvLabCubeRootTab[y];
                    l = (((y * labLScale - labLShift) + (1 << ((2 * lab_shift) - 1))) >> (2 * lab_shift));
                }
                else
                {
                    l = (((y * labLScale2) + (1 << ((lab_shift) - 1))) >> (lab_shift));
                    y = (((y * labSmallScale + labSmallShift) + (1 << ((lab_shift) - 1))) >> (lab_shift));
                }

                a = (((500 * (x - y)) + (1 << ((lab_shift) - 1))) >> (lab_shift)) + 129;
                b = (((200 * (y - z)) + (1 << ((lab_shift) - 1))) >> (lab_shift)) + 128;

                l = l > 255 ? 255 : l < 0 ? 0 : l;
                a = a > 255 ? 255 : a < 0 ? 0 : a;
                b = b > 255 ? 255 : b < 0 ? 0 : b;

                to->L = (byte)l;
                to->A = (byte)a;
                to->B = (byte)b;

                from++;
                to++;
            }
        }