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yuv420p 详解_YUV(yuv422、yuv420p、yuv420sp) convert to RGB

void convert_yuv420p_to_rgb_buffer(unsigned char* yuv, unsigned char* rgb, unsigned int width, unsigned int height)

{

int y, u, v;

int r, g, b;

unsigned char* rgbPixel = rgb;

unsigned char* yuvPixel = yuv;

unsigned char* uHeader = yuv + width * height;

unsigned char* vHeader = yuv + width * height + (width * height) / 4;

int half_width = width / 2;

for (int j = 0; j < height; j++) {

for (int i = 0; i < width; i++) {

y = *yuvPixel;

yuvPixel++;

u = *(uHeader + (i / 2 + (j / 2 * half_width)));

v = *(vHeader + (i / 2 + (j / 2 * half_width)));

// yuv to rgb, 整数、移位, 减少计算量

r = y + ((360 * (v - 128)) >> 8);

r = r > 255 ? 255 : (r < 0 ? 0 : r);

*rgbPixel = r;

rgbPixel++;

g = y - (((88 * (u - 128) + 184 * (v - 128))) >> 8);

g = g > 255 ? 255 : (g < 0 ? 0 : g);

*rgbPixel = g;

rgbPixel++;

b = y + ((455 * (u - 128)) >> 8);

b = b > 255 ? 255 : (b < 0 ? 0 : b);

*rgbPixel = b;

rgbPixel++;

}

}

}void convert_yuv420sp_to_rgb_buffer(unsigned char* yuv, unsigned char* rgb, unsigned int width, unsigned int height)

{

int y, u, v;

int r, g, b;

unsigned char* rgbPixel = rgb;

unsigned char* yuvPixel = yuv;

unsigned char* uHeader = yuv + width * height;

//unsigned char* vHeader = yuv + width * height + (width * height) / 4;

int half_width = width / 2;

for (int j = 0; j < height; j++) {

for (int i = 0; i < width; i++) {

y = *yuvPixel;

yuvPixel++;

u = *(uHeader + (i / 2 + (j / 2 * half_width)) * 2); // 注意: 因为是整数乘除, 这里 (i / 2 * 2) 不一定都等于 i, 不要简化。

v = *(uHeader + (i / 2 + (j / 2 * half_width)) * 2+1);

// yuv to rgb, 整数、移位, 减少计算量

r = y + ((360 * (v - 128)) >> 8);

r = r > 255 ? 255 : (r < 0 ? 0 : r);

*rgbPixel = r;

rgbPixel++;

g = y - (((88 * (u - 128) + 184 * (v - 128))) >> 8);

g = g > 255 ? 255 : (g < 0 ? 0 : g);

*rgbPixel = g;

rgbPixel++;

b = y + ((455 * (u - 128)) >> 8);

b = b > 255 ? 255 : (b < 0 ? 0 : b);

*rgbPixel = b;

rgbPixel++;

}

}

}void convert_yuyv_to_rgb_buffer(unsigned char* yuv, unsigned char* rgb, unsigned int width, unsigned int height)

{

unsigned int i;

unsigned char* rgbPixel = rgb;

unsigned char* yuvPixel = yuv;

int y0, u, y1, v;

int r, g, b;

for (i = 0; i < width * height / 2; i++) {

y0 = *yuvPixel;

yuvPixel++;

u = *yuvPixel;

yuvPixel++;

y1 = *yuvPixel;

yuvPixel++;

v = *yuvPixel;

yuvPixel++;

// yuv to rgb, 整数、移位, 减少计算量

r = y0 + ((360 * (v - 128)) >> 8);

r = r > 255 ? 255 : (r < 0 ? 0 : r);

*rgbPixel = r;

rgbPixel++;

g = y0 - (((88 * (u - 128) + 184 * (v - 128))) >> 8);

g = g > 255 ? 255 : (g < 0 ? 0 : g);

*rgbPixel = g;

rgbPixel++;

b = y0 + ((455 * (u - 128)) >> 8);

b = b > 255 ? 255 : (b < 0 ? 0 : b);

*rgbPixel = b;

rgbPixel++;

// yuv to rgb, 整数、移位, 减少计算量

r = y1 + ((360 * (v - 128)) >> 8);

r = r > 255 ? 255 : (r < 0 ? 0 : r);

*rgbPixel = r;

rgbPixel++;

g = y1 - (((88 * (u - 128) + 184 * (v - 128))) >> 8);

g = g > 255 ? 255 : (g < 0 ? 0 : g);

*rgbPixel = g;

rgbPixel++;

b = y1 + ((455 * (u - 128)) >> 8);

b = b > 255 ? 255 : (b < 0 ? 0 : b);

*rgbPixel = b;

rgbPixel++;

}

}