H264 YUV420视频翻转

h264解码后视频翻转，基于SDL overlay.

翻转YUV420：

 

void TurnPlanar(const unsigned char *srcp_y, unsigned char *dstp_y,
			  const unsigned char *srcp_u, unsigned char *dstp_u,
			  const unsigned char *srcp_v, unsigned char *dstp_v,
			  const int rowsize, const int height,
			  const int rowsizeUV, const int heightUV,
			  const int src_pitch_y, const int dst_pitch_y,
			  const int src_pitch_u, const int dst_pitch_uv,
			  const int src_pitch_v, const int direction)
{
	/*++++++++++++++++++++++++++++++++++++++++++
	(0,0)************************>x
	*
	*
	*
	*
	*
	*
	>
	y
	++++++++++++++++++++++++++++++++++++++++++++*/
	int y, x, offset;
	if (direction == 1) // Right
	{
		for(y=0; y

应用部分：

在设置编码参数时。如果侧翻，需要将width 和 height互换

pImg_convert_ctx = sws_getContext(FrameData.width,FrameData.height, FrameData.pix_fmt ,\
			FrameData.height, FrameData.width, PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);

 

AVPicture *pict = new AVPicture;
	pict->data[0] = bmp->pixels[0];
	pict->data[1] = bmp->pixels[2];
	pict->data[2] = bmp->pixels[1];
	pict->linesize[0] = bmp->pitches[0];
	pict->linesize[1] = bmp->pitches[2];
	pict->linesize[2] = bmp->pitches[1];

	// Convert the image into YUV format that SDL uses
	int nScale = sws_scale(pImg_convert_ctx, ((AVPicture *)FrameData.pFrame)->data, ((AVPicture *)FrameData.pFrame)->linesize,\
		                   0, FrameData.height, picttmp->data, picttmp->linesize);

	
	int pitch, pitchUV, align;
	align = screen->format->BitsPerPixel;
	pitch = (FrameData.width + align - 1)/align*align;
	pitchUV = (pitch+1)>>1;
	TurnPlanar(picttmp->data[0], pict->data[0], picttmp->data[1], pict->data[1], picttmp->data[2], pict->data[2],\
		FrameData.height, FrameData.width, FrameData.height/2, FrameData.width/2,\
		pitch, pitch, pitchUV, pitchUV, pitchUV, 1);//侧翻

 效果如下：