用OpenCV实现Photoshop算法_变为黑白图像

/* * BlackWhite Adjust * * Author: JoStudio */ #include "BlackWhite.hpp" #define SWAP(a, b, t) do { t = a; a = b; b = t; } while(0) #define CLIP_RANGE(value, min, max) ( (value) > (max) ? (max) : (((value) < (min)) ? (min) : (value)) ) #define COLOR_RANGE(value) CLIP_RANGE(value, 0, 255) //color index typedef enum COLOR_INDEX { INDEX_RED, INDEX_YELLOW, INDEX_GREEN, INDEX_CYAN, INDEX_BLUE, INDEX_MAGENTA } color_index_t; namespace cv { BlackWhite::BlackWhite() { //set to default settings red = 0.4; yellow = 0.6; green = 0.4; cyan = 0.6; blue = 0.2; magenta = 0.8; } BlackWhite::~BlackWhite() { } int BlackWhite::adjust(InputArray src, OutputArray dst) { Mat input = src.getMat(); if( input.empty() ) { return -1; } dst.create(src.size(), src.type()); Mat output = dst.getMat(); int blackWhiteParams[6]; blackWhiteParams[0] = CLIP_RANGE(red * 100, -100, 100); blackWhiteParams[1] = CLIP_RANGE(yellow * 100, -100, 100); blackWhiteParams[2] = CLIP_RANGE(green * 100, -100, 100); blackWhiteParams[3] = CLIP_RANGE(cyan * 100, -100, 100); blackWhiteParams[4] = CLIP_RANGE(blue * 100, -100, 100); blackWhiteParams[5] = CLIP_RANGE(magenta * 100, -100, 100); const uchar *in; uchar *out; int channels = input.channels(); int rows = input.rows; int cols = input.cols; uchar gray; int tmp; int values[3]; int indexes[3]; int ratio_max; int ratio_max_mid; for (int y = 0; y < rows; y ++ ) { in = input.ptr<uchar>(y); out = output.ptr<uchar>(y); for (int x = 0; x < cols; x ++) { //read RGB into values, set index in indexes. values[0] = in[0]; values[1] = in[1]; values[2] = in[2]; indexes[0]=INDEX_BLUE; indexes[1]=INDEX_GREEN; indexes[2]=INDEX_RED; //sort values and indexes if ( values[1] > values[0] ) { SWAP(values[0], values[1], tmp); SWAP(indexes[0], indexes[1], tmp); } if ( values[2] > values[1] ) { SWAP(values[1], values[2], tmp); SWAP(indexes[1], indexes[2], tmp); } if ( values[1] > values[0] ) { SWAP(values[0], values[1], tmp); SWAP(indexes[0], indexes[1], tmp); } //get ratio_max ratio_max = blackWhiteParams[ indexes[0] ]; //calculate ratio_max_mid if ( indexes[0] == INDEX_RED ) { tmp = (indexes[1] == INDEX_GREEN) ? INDEX_YELLOW : INDEX_CYAN; } else if ( indexes[0] == INDEX_GREEN ) { tmp = (indexes[1] == INDEX_RED) ? INDEX_YELLOW : INDEX_CYAN ; } else { tmp = (indexes[1] == INDEX_RED) ? INDEX_MAGENTA : INDEX_CYAN; } ratio_max_mid = blackWhiteParams[ tmp ]; //calculate gray = (max - mid) * ratio_max + (mid - min) * ratio_max_mid + min gray = COLOR_RANGE ( ( (values[0] - values[1]) * ratio_max + (values[1] - values[2]) * ratio_max_mid + values[2] * 100 ) / 100 ); //save to ouput *out++ = gray; *out++ = gray; *out++ = gray; //move pointer forward in += 3; for (int j = 0; j < channels - 3; j++) { *out++ = *in++; } } } return 0; } } /* namespace cv */