/// <summary> /// Computes the weighted variance of a box. /// </summary> /// <param name="c">The cube.</param> /// <returns>The result.</returns> private float Variance(ref Data.Box c) { float dr = WuQuant.Volume(ref c, this.vmr); float dg = WuQuant.Volume(ref c, this.vmg); float db = WuQuant.Volume(ref c, this.vmb); float da = WuQuant.Volume(ref c, this.vma); float xx = this.m2[WuQuant.GetIndex(c.R1, c.G1, c.B1, c.A1)] - this.m2[WuQuant.GetIndex(c.R1, c.G1, c.B1, c.A0)] - this.m2[WuQuant.GetIndex(c.R1, c.G1, c.B0, c.A1)] + this.m2[WuQuant.GetIndex(c.R1, c.G1, c.B0, c.A0)] - this.m2[WuQuant.GetIndex(c.R1, c.G0, c.B1, c.A1)] + this.m2[WuQuant.GetIndex(c.R1, c.G0, c.B1, c.A0)] + this.m2[WuQuant.GetIndex(c.R1, c.G0, c.B0, c.A1)] - this.m2[WuQuant.GetIndex(c.R1, c.G0, c.B0, c.A0)] - this.m2[WuQuant.GetIndex(c.R0, c.G1, c.B1, c.A1)] + this.m2[WuQuant.GetIndex(c.R0, c.G1, c.B1, c.A0)] + this.m2[WuQuant.GetIndex(c.R0, c.G1, c.B0, c.A1)] - this.m2[WuQuant.GetIndex(c.R0, c.G1, c.B0, c.A0)] + this.m2[WuQuant.GetIndex(c.R0, c.G0, c.B1, c.A1)] - this.m2[WuQuant.GetIndex(c.R0, c.G0, c.B1, c.A0)] - this.m2[WuQuant.GetIndex(c.R0, c.G0, c.B0, c.A1)] + this.m2[WuQuant.GetIndex(c.R0, c.G0, c.B0, c.A0)]; return(xx - (((dr * dr) + (dg * dg) + (db * db) + (da * da)) / WuQuant.Volume(ref c, this.vwt))); }
/// <summary> /// Generates the quantized result. /// </summary> /// <param name="image">The image.</param> /// <param name="colorCount">The color count.</param> /// <param name="width">Width of image</param> /// <param name="height">Height of image</param> /// <param name="destPixels">Pixel values are written here. Must provide width*height memory.</param> /// <param name="padMultiple4">True to write zero padding to make row bytes multiple of 4</param> /// <returns>Receives colors</returns> private unsafe uint[] GenerateResult(uint *image, int colorCount, int width, int height, byte *destPixels, bool padMultiple4) { uint[] palette = new uint[colorCount]; // rows must be a multiple of 4, hence padding up to 3 bytes for 8-bit indexed pixels int widthMod4 = width % 4; int widthZeros = widthMod4 != 0 ? 4 - widthMod4 : 0; for (int k = 0; k < colorCount; k++) { this.Mark(ref this.cube[k], (byte)k); float weight = WuQuant.Volume(ref this.cube[k], this.vwt); if (weight != 0) { uint a = (byte)(WuQuant.Volume(ref this.cube[k], this.vma) / weight); uint r = (byte)(WuQuant.Volume(ref this.cube[k], this.vmr) / weight); uint g = (byte)(WuQuant.Volume(ref this.cube[k], this.vmg) / weight); uint b = (byte)(WuQuant.Volume(ref this.cube[k], this.vmb) / weight); palette[k] = (a << 24) | (r << 16) | (g << 8) | b; } else { palette[k] = 0xFF000000; } } for (int ri = 0; ri < height; ri++) { for (int ci = 0; ci < width; ci++) { uint pix = image[0]; uint a = ((pix & 0xFF000000) >> 24) >> (8 - WuQuant.INDEXALPHABITS); uint r = ((pix & 0x00FF0000) >> 16) >> (8 - WuQuant.INDEXBITS); uint g = ((pix & 0x0000FF00) >> 8) >> (8 - WuQuant.INDEXBITS); uint b = (pix & 0x000000FF) >> (8 - WuQuant.INDEXBITS); int ind = WuQuant.GetIndex((int)r + 1, (int)g + 1, (int)b + 1, (int)a + 1); destPixels[0] = this.tag[ind]; destPixels++; image++; } // write additional zero bytes if requested if (padMultiple4) { for (int c = 0; c < widthZeros; c++) { destPixels[0] = 0x00; destPixels++; } } } return(palette); }
private static int Top(ref Data.Box cube, int direction, int position, int[] moment) { switch (direction) { // Red case 3: return(moment[WuQuant.GetIndex(position, cube.G1, cube.B1, cube.A1)] - moment[WuQuant.GetIndex(position, cube.G1, cube.B1, cube.A0)] - moment[WuQuant.GetIndex(position, cube.G1, cube.B0, cube.A1)] + moment[WuQuant.GetIndex(position, cube.G1, cube.B0, cube.A0)] - moment[WuQuant.GetIndex(position, cube.G0, cube.B1, cube.A1)] + moment[WuQuant.GetIndex(position, cube.G0, cube.B1, cube.A0)] + moment[WuQuant.GetIndex(position, cube.G0, cube.B0, cube.A1)] - moment[WuQuant.GetIndex(position, cube.G0, cube.B0, cube.A0)]); // Green case 2: return(moment[WuQuant.GetIndex(cube.R1, position, cube.B1, cube.A1)] - moment[WuQuant.GetIndex(cube.R1, position, cube.B1, cube.A0)] - moment[WuQuant.GetIndex(cube.R1, position, cube.B0, cube.A1)] + moment[WuQuant.GetIndex(cube.R1, position, cube.B0, cube.A0)] - moment[WuQuant.GetIndex(cube.R0, position, cube.B1, cube.A1)] + moment[WuQuant.GetIndex(cube.R0, position, cube.B1, cube.A0)] + moment[WuQuant.GetIndex(cube.R0, position, cube.B0, cube.A1)] - moment[WuQuant.GetIndex(cube.R0, position, cube.B0, cube.A0)]); // Blue case 1: return(moment[WuQuant.GetIndex(cube.R1, cube.G1, position, cube.A1)] - moment[WuQuant.GetIndex(cube.R1, cube.G1, position, cube.A0)] - moment[WuQuant.GetIndex(cube.R1, cube.G0, position, cube.A1)] + moment[WuQuant.GetIndex(cube.R1, cube.G0, position, cube.A0)] - moment[WuQuant.GetIndex(cube.R0, cube.G1, position, cube.A1)] + moment[WuQuant.GetIndex(cube.R0, cube.G1, position, cube.A0)] + moment[WuQuant.GetIndex(cube.R0, cube.G0, position, cube.A1)] - moment[WuQuant.GetIndex(cube.R0, cube.G0, position, cube.A0)]); // Alpha case 0: return(moment[WuQuant.GetIndex(cube.R1, cube.G1, cube.B1, position)] - moment[WuQuant.GetIndex(cube.R1, cube.G1, cube.B0, position)] - moment[WuQuant.GetIndex(cube.R1, cube.G0, cube.B1, position)] + moment[WuQuant.GetIndex(cube.R1, cube.G0, cube.B0, position)] - moment[WuQuant.GetIndex(cube.R0, cube.G1, cube.B1, position)] + moment[WuQuant.GetIndex(cube.R0, cube.G1, cube.B0, position)] + moment[WuQuant.GetIndex(cube.R0, cube.G0, cube.B1, position)] - moment[WuQuant.GetIndex(cube.R0, cube.G0, cube.B0, position)]); default: throw new ArgumentOutOfRangeException("direction"); } }