c_cpp 图像格式转换

Posted 2021-05-14

void NV21_T_RGB( unsigned char *yuyv , unsigned char *rgb,unsigned int width , unsigned int height )
{
    const int nv_start = width * height ;
    HI_U32  i, j, index = 0, rgb_index = 0;
    HI_U8 y, u, v;
    int r, g, b, nv_index = 0;


    for(i = 0; i <  height ; i++)
    {
        for(j = 0; j < width; j ++){
            //nv_index = (rgb_index / 2 - width / 2 * ((i + 1) / 2)) * 2;
            nv_index = i / 2  * width + j - j % 2;

            y = yuyv[rgb_index];
            v = yuyv[nv_start + nv_index ];
            u = yuyv[nv_start + nv_index + 1];


            r = y + (140 * (v-128))/100;  //r
            g = y - (34 * (u-128))/100 - (71 * (v-128))/100; //g
            b = y + (177 * (u-128))/100; //b

            if(r > 255)   r = 255;
            if(g > 255)   g = 255;
            if(b > 255)   b = 255;
            if(r < 0)     r = 0;
            if(g < 0)     g = 0;
            if(b < 0)     b = 0;

            index = j + i  * width;
            //bgr planner排列
            //rgb[index] = b;
            //rgb[index+nv_start] = g;
            //rgb[index+2*nv_start] = r;
            //bgr排列
            rgb[index * 3+0] = b;
            rgb[index * 3+1] = g;
            rgb[index * 3+2] = r;
            rgb_index++;
        }
    }
}