YUV422转RGB24

int DeckLinkCaptureDelegate::convert_yuv_to_rgb_pixel(int y, int u, int v)
{
        unsigned int pixel32 = 0;
        unsigned char *pixel = (unsigned char *)&pixel32;
        int r, g, b;
        r = y + (1.370705 * (v-128));
        g = y - (0.698001 * (v-128)) - (0.337633 * (u-128));
        b = y + (1.732446 * (u-128));
        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;
        pixel[0] = r ;
        pixel[1] = g ;
        pixel[2] = b ;
        return pixel32;
}

int DeckLinkCaptureDelegate::convert_yuv_to_rgb_buffer(unsigned char *yuv, unsigned char *rgb, unsigned int width, unsigned int height)
{
        unsigned int in, out = 0;
        unsigned int pixel_16;
        unsigned char pixel_24[3];
        unsigned int pixel32;
        int y0, u, y1, v;

        for(in = 0; in < width * height * 2; in += 4)
        {
                pixel_16 =
                                yuv[in + 3] << 24 |
                                yuv[in + 2] << 16 |
                                yuv[in + 1] <<  8 |
                                yuv[in + 0];
                y0 = (pixel_16 & 0x000000ff);
                u  = (pixel_16 & 0x0000ff00) >>  8;
                y1 = (pixel_16 & 0x00ff0000) >> 16;
                v  = (pixel_16 & 0xff000000) >> 24;
                pixel32 = convert_yuv_to_rgb_pixel(y0, u, v);
                pixel_24[0] = (pixel32 & 0x000000ff);
                pixel_24[1] = (pixel32 & 0x0000ff00) >> 8;
                pixel_24[2] = (pixel32 & 0x00ff0000) >> 16;
                rgb[out++] = pixel_24[0];
                rgb[out++] = pixel_24[1];
                rgb[out++] = pixel_24[2];
                pixel32 = convert_yuv_to_rgb_pixel(y1, u, v);
                pixel_24[0] = (pixel32 & 0x000000ff);
                pixel_24[1] = (pixel32 & 0x0000ff00) >> 8;
                pixel_24[2] = (pixel32 & 0x00ff0000) >> 16;
                rgb[out++] = pixel_24[0];
                rgb[out++] = pixel_24[1];
                rgb[out++] = pixel_24[2];
        }
        return 0;

}

mrgb = (unsigned char*)malloc(1280 * 720 * 3 * sizeof(char));
mImage = new QImage(mrgb, 1280, 720, QImage::Format_RGB888);

convert_yuv_to_rgb_buffer((uchar*)frameBytes,mrgb,1280, 720);
mImage->loadFromData((uchar*)mrgb, 1280 * 720 * 3 * sizeof(char));
bool bsave = mImage->save("/home/johnson/2.bmp","bmp");