lecture02_subprogram.c

对DSP视频开发板的初级熟悉

//--------------- lecture02_subprogram.c  start--------------
void RGB24_to_YUV444(
	unsigned char * RGB_in, 
	unsigned char * YUV_out,
	short width,short height)
{	
    int i,N;
    short tmpY,tmpU,tmpV;
    unsigned char * p_RGB, * p_YUV;
    
    N = (int)(width * height);
    p_RGB = RGB_in;
    p_YUV = YUV_out;

    for( i=0; i<N; i++ ) 
    {    	
	tmpY = 0.2990*(*p_RGB) + 0.5870*(*(p_RGB+1))  +	0.1140*(*(p_RGB+2));
	tmpU = -0.1684*(*p_RGB) - 0.3316*(*(p_RGB+1)) + 0.5000*(*(p_RGB+2))+128;
	tmpV = 0.5000*(*p_RGB) - 0.4187*(*(p_RGB+1)) - 0.0813*(*(p_RGB+2))+128 ;
		
	if (tmpY <0)		tmpY = 0;
	if (tmpY > 255)		tmpY = 255;
	if (tmpU <0)		tmpU = 0;
	if (tmpU > 255)		tmpU = 255;
	if (tmpV <0)		tmpV = 0;
	if (tmpV > 255)		tmpV = 255;
	
	*p_YUV = 	(unsigned char) tmpU;
	*(p_YUV+1) = (unsigned char)tmpY;
	*(p_YUV+2) = (unsigned char)tmpV;
	
	p_RGB +=3;
	p_YUV +=3;
	}
}

void YUV444_to_YUV422(
	unsigned char * YUV444_in, 
	unsigned char * YUV422_out,
	short width,short height)
{   int i,N;
    unsigned char * p_in, * p_out;
    
    N = (int)(width * height);
    p_in = YUV444_in;
    p_out = YUV422_out;

    for( i=0; i<(N/2); i++ ) 
    {	*p_out = 	*p_in;
		*(p_out+1) = *(p_in+1);
		*(p_out+2) = *(p_in+2);
		*(p_out+3) = *(p_in+4);
		
		p_in +=6;
		p_out +=4;
	}
}

void Rotate_image (
	unsigned char * image_in, 
	unsigned char * image_out,
	short width,short height)
{	
	int i ,j ,N;
	unsigned char *p_in, *p_out;
	
	N=(int)(width*height);
	p_in = image_in;
	p_out = image_out;
	
	for(j=width/2-1; j>=0; j--)
	{
		for(i=0; i<height; i++)
		{
			*p_out = *(p_in+j*4+i*width*2);
			*(p_out+1) = *(p_in+j*4+i*width*2+3);
			*(p_out+2) = *(p_in+j*4+i*width*2+2);
			p_out +=3;
			i++;
			*p_out = *(p_in+j*4+i*width*2+3);
			p_out++;
		}
		for(i=0; i<height; i++)
		{
			*p_out = *(p_in+j*4+i*width*2);
			*(p_out+1) = *(p_in+j*4+i*width*2+1);
			*(p_out+2) = *(p_in+j*4+i*width*2+2);
			p_out +=3;
			i++;
			*p_out = *(p_in+j*4+i*width*2+1);
			p_out++;
		}
	}
}

void Get_NTSC_frame_from_ITU656(unsigned char* buffer_in,unsigned char *buffer_out)
{
	int i,j;
	unsigned char *p_in, *p_out;
	p_in = buffer_in;
	p_out = buffer_out;
	p_out += 1440;
	for(j=0;j<263;)
	{
		if(*p_in == 0xFF && *(p_in+1)==0 && *(p_in+2)==0)
		{
			p_in += 3;
			if((*p_in & 0x20) == 0x20)
			{
				do
				{
					p_in += 1716; 
					j++;
				}while((*p_in & 0x20) == 0x20);
				
				if((*p_in & 0x10) == 0x10)
				{
					p_in += 272;
				}
			}
			else if((*p_in & 0x10) == 0x10)
			{
				p_in += 272;   //268+4
			}
			
			p_in ++;
			for(i=0;i<1440;i++)
			{
				*p_out = *p_in;
				p_out ++;
				p_in ++;
			}
			p_out += 1440;
			j++;
		}
		else p_in++;
	}
	
	p_out = buffer_out;
	
	for(j=0;j<262;)
	{
		if(*p_in == 0xFF && *(p_in+1)==0 && *(p_in+2)==0)
		{
			p_in += 3;
			if((*p_in & 0x20) == 0x20)
			{
				do
				{
					p_in += 1716; 
					j++;
				}while((*p_in & 0x20) == 0x20);
				
				if((*p_in & 0x10) == 0x10)
				{
					p_in += 272;
				}
			}
			else if((*p_in & 0x10) == 0x10)
			{
				p_in += 272;   //268+4
			}
			
			p_in ++;
			for(i=0;i<1440;i++)
			{
				*p_out = *p_in;
				p_out ++;
				p_in ++;
			}
			
			p_out += 1440;
			j++;
		}
		else p_in++;
	}
}


//--------------- lecture02_subprogram.c  end-----------------