[問題] HSI RGB轉換

看板C_and_CPP (C/C++)作者tracy23 (tracy)時間15年前 (2010/11/22 01:28)推噓4(4推 0噓 6→)

留言10則, 3人參與討論串1/1

將圖從RGB轉HSI 再從HSI轉回RGB 程式曾經轉出正確的圖(就HSI轉RGB再轉回來的圖是一樣的) 但加入HE後就變怪了就算去掉HE的部分出來的圖還是不對我有帶值下去跑過輸入的值跟輸出的值一樣可是圖就是不對還把錯誤的圖的值讀進去竟然還會跟正確的圖一樣....... 我覺得問題應該是出在"強制轉換"的地方請問要怎麼解決呢?? 拜託了 >"< 感謝附上程式碼 #include <iostream> #include <stdio.h> #include <stdlib.h> #include <cmath> using namespace std; #define width 512 #define height 512 #define pi 3.14159 void read_file(unsigned char* r_data, unsigned char *g_data, unsigned char* b_data) { FILE *fd; fd = fopen("lena.raw", "rb"); static char data[width*height*3]; fread(data, sizeof(data) ,sizeof(unsigned char), fd); for (int i=0; i<width*height; i++) { r_data[i] = data[i]; g_data[i] = data[i+width*height]; b_data[i] = data[i+width*height*2]; } fclose(fd); } void write_file(unsigned char* r_data, unsigned char *g_data, unsigned char* b_data, char filename[]) { FILE *fd; fd = fopen(filename, "wb"); static char data2[width*height*3]; for (int i=0; i<width*height; i++) { data2[i] = r_data[i]; data2[i+width*height] = g_data[i]; data2[i+width*height*2] = b_data[i]; } fwrite(data2, sizeof(data2) ,sizeof(unsigned char), fd); fclose(fd); } void HSI_RGB(unsigned char* r_data, unsigned char *g_data, unsigned char* b_data, double* R, double* G, double* B, double* H, double* S, double* I, char filename[]) { static double h[width*height]; static double s[width*height]; static double i[width*height]; for (int j=0;j <width*height; j++) { h[j] = H[ j ]*pi/180.0; s[j] = S[j]/100.0; i[j] = I[j]/255.0; if (j==0) if (h[j] < 2*pi/3.0) { B[j] = i[j]*(1-s[j]); R[j] = i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j]))); G[j] = 3*i[j] - (i[j]*(1-s[j])) - (i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j])))); } else if (2*pi/3.0 <= h[j] && 4*pi/3.0 > h[j]) { h[j] = h[j] - 2*pi/3.0; R[j] = i[j]*(1-s[j]); G[j] = i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j]))); B[j] = 3*i[j] - (i[j]*(1-s[j])) - (i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j])))); } else if (4*pi/3.0 <= h[j] && 2*pi > h[j]) { h[j] = h[j] - 4*pi/3.0; G[j] = i[j]*(1-s[j]); B[j] = i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j]))); R[j] = 3*i[j] - (i[j]*(1-s[j])) - (i[j]*(1+ (s[j]*cos(h[j])/cos(pi/3.0 - h[j])))); } G[j] = G[j]*255; B[j] = B[j]*255; R[j] = R[j]*255; R[j] = (R[j] > 255) ? 255 : R[j]; G[j] = (G[j] > 255) ? 255 : G[j]; B[j] = (B[j] > 255) ? 255 : B[j]; r_data[j] = (unsigned char) R[j]; g_data[j] = (unsigned char) G[j]; b_data[j] = (unsigned char) B[j]; } write_file(r_data, g_data, b_data, filename); } void RGB_HSI(unsigned char* r_data, unsigned char *g_data, unsigned char* b_data) { static double R[width*height]; static double G[width*height]; static double B[width*height]; static double theta[width*height]; static double H[width*height]; static double S[width*height]; static double I[width*height]; for (int i=0; i< width*height; i++) { R[i] = (double) r_data[i]/((double)r_data[i] + (double)g_data[i] + (double)b_data[i]); G[i] = (double) g_data[i]/((double)r_data[i] + (double)g_data[i] + (double)b_data[i]); B[i] = (double) b_data[i]/((double)r_data[i] + (double)g_data[i] + (double)b_data[i]); double a1 = 0.5*((R[i] - G[i]) + (R[i] - B[i])); double a2 = pow(pow(R[i] - G[i],2.0) + (R[i] - B[i])*(G[i] - B[i]),0.5); double min = (R[i] > G[i]) ? G[i]:R[i]; min = (min > B[i]) ? B[i]:min; //----------H if (B[i] > G[i]) H[i] = 2*pi - acos(a1/a2); else H[i] = acos(a1/a2); //----------S S[i] = 1-3*min; //----------I I[i] = ((double) r_data[i]+(double) g_data[i]+(double) b_data[i])/(3.0*255.0); H[i] = H[i]*180/pi; S[i] = S[i]*100; I[i] = I[i]*255; } HSI_RGB(r_data, g_data, b_data, R, G, B, H, S, I, "lena_t.raw"); } int main() { unsigned char r_data[width*height]; unsigned char g_data[width*height]; unsigned char b_data[width*height]; read_file(r_data, g_data, b_data); RGB_HSI(r_data, g_data, b_data); return 0; } -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 163.25.118.153 ※ 編輯: tracy23 來自: 163.25.118.153 (11/22 01:35) ※ 編輯: tracy23 來自: 163.25.118.153 (11/22 03:04)

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