此文版權屬於作者所有，任何人、媒體或者網站轉載、借用都必須征得作者本人同意！ [cpp] typedef struct yuv2rgb_rgb_t { int r, g, b; } yuv2rgb_rgb_t; static inline void rgb_calc(yuv2rgb_rgb_t* rgb, int Y, int Cr, int Cb) { rgb->r = Y + Cr + (Cr >> 2) + (Cr >> 3) + (Cr >> 5); if (rgb->r < 0) rgb->r = 0; else if (rgb->r > 255) rgb->r = 255; rgb->g = Y - (Cb >> 2) + (Cb >> 4) + (Cb >> 5) - (Cr >> 1) + (Cr >> 3) + (Cr >> 4) + (Cr >> 5); if (rgb->g < 0) rgb->g = 0; else if (rgb->g > 255) rgb->g = 255; rgb->b = Y + Cb + (Cb >> 1) + (Cb >> 2) + (Cb >> 6); if (rgb->b < 0) rgb->b = 0; else if (rgb->b > 255) rgb->b = 255; } #define YUV2RGB_SET_RGB(p, rgb) *p++ = (unsigned char)rgb.r; *p++ = (unsigned char)rgb.g; *p++ = (unsigned char)rgb.b; *p++ = 0xff static void yuv420sp_to_rgba(unsigned char const* yuv420sp, int width, int height, unsigned char* rgba) { const int width4 = width * 4; unsigned char const* y0_ptr = yuv420sp; unsigned char const* y1_ptr = yuv420sp + width; unsigned char const* cb_ptr = yuv420sp + (width * height); unsigned char const* cr_ptr = cb_ptr + 1; unsigned char* rgba0 = rgba; unsigned char* rgba1 = rgba + width4; int Y00, Y01, Y10, Y11; int Cr = 0; int Cb = 0; int r, c; yuv2rgb_rgb_t rgb00, rgb01, rgb10, rgb11; for (r = 0; r < height / 2; ++r) { for (c = 0; c < width / 2; ++c, cr_ptr += 2, cb_ptr += 2) { Cr = *cr_ptr; Cb = *cb_ptr; if (Cb < 0) Cb += 127; else Cb -= 128; if (Cr < 0) Cr += 127; else Cr -= 128; Y00 = *y0_ptr++; Y01 = *y0_ptr++; Y10 = *y1_ptr++; Y11 = *y1_ptr++; rgb_calc(&rgb00, Y00, Cr, Cb); rgb_calc(&rgb01, Y01, Cr, Cb); rgb_calc(&rgb10, Y10, Cr, Cb); rgb_calc(&rgb11, Y11, Cr, Cb); YUV2RGB_SET_RGB(rgba0, rgb00); YUV2RGB_SET_RGB(rgba0, rgb01); YUV2RGB_SET_RGB(rgba1, rgb10); YUV2RGB_SET_RGB(rgba1, rgb11); } y0_ptr += width; y1_ptr += width; rgba0 += width4; rgba1 += width4; } }
