YUV RGB 转换

在网上看到一个开源项目的代码，写的非常整洁，易懂，特此记录下来，网址忘了，还望见谅！！

[cpp] view plaincopyprint?

1. <span style="font-size: 14px;">#include <math.h> 
2. #include <stdint.h> 
3.   
4. #define ALIGN_2K(x) ((x + 2047) & ~ 2047) 
5. struct Buffer { 
6.     void * data; 
7.     size_t size; 
8.     size_t width, height; 
9. }; 
10.   
11. static int convertRGB888toRGB565(struct Buffer src,struct Buffer dst); 
12. static int convertRGB888toYCbCr420SP(struct Buffer src,struct Buffer dst); 
13.   
14. int main() { 
15.     struct Buffer src, dst; 
16.   
17.     FILE * in = fopen("input.yuv","rb"); 
18.     FILE * out = fopen("output.yuv","wb"); 
19.     int width = 800; 
20.     int height = 480; 
21.     uint8_t *srcData = malloc(width * height * 3); 
22.     uint8_t *dstData = malloc(width * height + ALIGN_2K(width * height)); 
23.     fread(srcData, width * height * 3, 1, in); 
24.   
25.     src.data = srcData; 
26.     src.size = width * height * 3; 
27.     src.width = WIDTH; 
28.     src.height = HEIGHT; 
29.   
30.     dst.data = dstData; 
31.     dst.size = width * height + ALIGN_2K(width * height); 
32.     dst.width = WIDTH; 
33.     dst.height = HEIGHT; 
34.      
35.     convertRGB888toYCbCr420SP(src, dst); 
36.   
37.     fwrite(dstData, width * height + ALIGN_2K(width * height), 1, out); 
38.   
39.     free(srcData); 
40.     free(dstData); 
41.     fclose(in); 
42.     fclose(out); 
43.   
44.     return 0; 
45.   
46.   
47. } 
48.   
49. static int convertRGB888toRGB565(struct Buffer src,struct Buffer dst) { 
50.     uint8_t *srcData, *dstData; 
51.   
52.     srcData = (uint8_t *)src.data; 
53.     dstData = (uint8_t *)dst.data; 
54.   
55.     for (int c = 0, i = 0; c < src.width * src.height;) { 
56.             //scale down each component to 5 or 6 bits 
57.             uint8_t r, g, b; 
58.             r = srcData[c++]; 
59.             g = srcData[c++]; 
60.             b = srcData[c++]; 
61.             r = (uint8_t)((srcData[c++]/255.0)*31); //R component 
62.             g = (uint8_t)((srcData[c++]/255.0)*63); //G component 
63.             b = (uint8_t)((srcData[c++]/255.0)*31); //B component 
64.             dstData[i++] = ((r & 0x1f) << 3) | ((g >> 3) & 0x7); //R (5 bits) +  G (upper 3 bits) 
65.             dstData[i++] = ((g & 0x7) << 5) | (b & 0x1f); //G (lower 3 bits) + B (5 bits) 
66.     } 
67.   
68.     return 0; 
69. } 
70.   
71.   
72. static int convertRGB888toYCbCr420SP(struct Buffer src,struct Buffer dst) { 
73.     uint8_t *srcData, *dstData; 
74.   
75.     srcData = (uint8_t *)src.data; 
76.     dstData = (uint8_t *)dst.data; 
77.   
78.     //derive the luma 
79.     for (int c = 0, i = 0, j = 0; c < src.width * src.height * 3;) { 
80.         uint8_t r, g, b; 
81.         r = srcData[c++]; 
82.         g = srcData[c++]; 
83.         b = srcData[c++]; 
84.         //stolen from wikipedia 
85.         uint8_t y, cb, cr; 
86.   
87.         y = (uint8_t)(16 + (65.481 * r + 128.553 * g + 24.966 * b)/256); 
88.         cb = (uint8_t)(128 + (-37.979 * r - 74.203 * g + 112 * b)/256); 
89.         cr = (uint8_t)(128 + (112 * r - 93.786 * g - 18.214 * b)/256); 
90.         dstData[i++] = y; 
91.         (dstData + ALIGN_2K(src.width * src.height))[j++] = cb; 
92.         (dstData + ALIGN_2K(src.width * src.height))[j++] = cr; 
93.     } 
94.     return 0; 
95. }</span> 

<span style="font-size:14px;">#include <math.h>#include <stdint.h> #define ALIGN_2K(x) ((x + 2047) & ~ 2047)struct Buffer {    void * data;    size_t size;    size_t width, height;}; static int convertRGB888toRGB565(struct Buffer src, struct Buffer dst);static int convertRGB888toYCbCr420SP(struct Buffer src, struct Buffer dst); int main() {    struct Buffer src, dst;     FILE * in = fopen("input.yuv", "rb");    FILE * out = fopen("output.yuv", "wb");    int width = 800;    int height = 480;    uint8_t *srcData = malloc(width * height * 3);    uint8_t *dstData = malloc(width * height + ALIGN_2K(width * height));    fread(srcData, width * height * 3, 1, in);     src.data = srcData;    src.size = width * height * 3;    src.width = WIDTH;    src.height = HEIGHT;     dst.data = dstData;    dst.size = width * height + ALIGN_2K(width * height);    dst.width = WIDTH;    dst.height = HEIGHT;        convertRGB888toYCbCr420SP(src, dst);     fwrite(dstData, width * height + ALIGN_2K(width * height), 1, out);     free(srcData);    free(dstData);    fclose(in);    fclose(out);     return 0;  } static int convertRGB888toRGB565(struct Buffer src, struct Buffer dst) {    uint8_t *srcData, *dstData;     srcData = (uint8_t *)src.data;    dstData = (uint8_t *)dst.data;     for (int c = 0, i = 0; c < src.width * src.height;) {            //scale down each component to 5 or 6 bits            uint8_t r, g, b;            r = srcData[c++];            g = srcData[c++];            b = srcData[c++];            r = (uint8_t)((srcData[c++]/255.0)*31); //R component            g = (uint8_t)((srcData[c++]/255.0)*63); //G component            b = (uint8_t)((srcData[c++]/255.0)*31); //B component            dstData[i++] = ((r & 0x1f) << 3) | ((g >> 3) & 0x7); //R (5 bits) +  G (upper 3 bits)            dstData[i++] = ((g & 0x7) << 5) | (b & 0x1f); //G (lower 3 bits) + B (5 bits)    }     return 0;}  static int convertRGB888toYCbCr420SP(struct Buffer src, struct Buffer dst) {    uint8_t *srcData, *dstData;     srcData = (uint8_t *)src.data;    dstData = (uint8_t *)dst.data;     //derive the luma    for (int c = 0, i = 0, j = 0; c < src.width * src.height * 3;) {        uint8_t r, g, b;        r = srcData[c++];        g = srcData[c++];        b = srcData[c++];        //stolen from wikipedia        uint8_t y, cb, cr;         y = (uint8_t)(16 + (65.481 * r + 128.553 * g + 24.966 * b)/256);        cb = (uint8_t)(128 + (-37.979 * r - 74.203 * g + 112 * b)/256);        cr = (uint8_t)(128 + (112 * r - 93.786 * g - 18.214 * b)/256);        dstData[i++] = y;        (dstData + ALIGN_2K(src.width * src.height))[j++] = cb;        (dstData + ALIGN_2K(src.width * src.height))[j++] = cr;    }    return 0;}</span>