imgcmc.c

以TI 公司的OMAP5910为例

//////////////////////////////////////////////////////////////////////////
//            Copyright (C) 2004, Eyoka @ Microunit
//                           All Rights Reserved
//________________________________________________________________________
//
// FILENAME:    imgcmc.c
// PROJECT:     High-Resolution Video System On OMAP
// MODULE:      Image Color Mode Converter
// DESCRIPTION: Converting images between different color-modes.
// TARGET CPU:  DSP-C55xx of OMAP5910
// VERSION:     1.1
//________________________________________________________________________
//
// REVISE HISTORY
// DATE         VERSION AUTHOR  DESCRIPTION
// 2004-10-22   1.1     Eyoka   Data order changed due to DSPMMU ENDIANISM
//                              Convertion cancelled.
// 2004-10-13   1.0     Eyoka   First release.
//////////////////////////////////////////////////////////////////////////

#include "imgcmc.h"
#include "dspdma.h"


/////////////////////////////////////////////////////////////////////
// GLOBAL VARIABLES
/////////////////////////////////////////////////////////////////////

// double buffering for Camera YUYV in
WORD In_buf_1[320];
WORD In_buf_2[320];

// double buffering for Out
WORD Out_buf_1[320];
WORD Out_buf_2[320];


/////////////////////////////////////////////////////////////////////
// FUNCTIONS
/////////////////////////////////////////////////////////////////////

//___________________________________________________________________
// Function: IMG_ConvertColorMode
// Usage: Convert color-mode of a whole image.
// Parameters:
//    hIn			- handle of the input image
//    hOut			- handle of the result image
// Return Values:
//    N/A
//___________________________________________________________________
// Do NOT support windowing
// Support YUYV->RGB565 only now
// if size_out > size_in, crop input.
// if size_out < size_in, output is filled with black.(NOT tested)
void IMG_ConvertColorMode(IMG_HANDLE hIn, IMG_HANDLE hOut)
{
	short i;
	WORD nRows = hOut->height;		// rows to process
	WORD sizeRead = hOut->width;	// pixels to read each row
	WORD empty_height = 0;			// rows to fill black

	// data BYTE address in SDRAM
	DWORD addrRAW = hIn->addr;
	DWORD addrOut = hOut->addr;

	// background transfer buffers
	WORD *pIn_Tran = In_buf_1;
	WORD *pOut_Tran = Out_buf_1;

	// foreground process buffers
	WORD *pIn_Proc = In_buf_2;
	WORD *pOut_Proc = Out_buf_2;

	// temp pointer for swapping
	WORD *ptr;

	// check size
	if(hOut->height > hIn->height)
	{
		empty_height = hOut->height - hIn->height;
		nRows = hIn->height;
	}

	if(hOut->width > hIn->width)
	{
		sizeRead = hIn->width;
	}

	// read first line to input buffer
	DMA_SD2DA(pIn_Tran, addrRAW, sizeRead);
	addrRAW += hIn->width * 2;

	// start double buffering loop
	for(i=0; i<nRows; i++)
	{
		// swap input buffer
		ptr = pIn_Tran;
		pIn_Tran = pIn_Proc;
		pIn_Proc = ptr;
		
		// start input background transfer
		DMA_SD2DA(pIn_Tran, addrRAW, sizeRead);
		addrRAW += hIn->width * 2;

		// convert color-mode
		IMGCMC_YUYV_RGB565(pIn_Proc, pOut_Proc, sizeRead);

		// swap Out buffer
		ptr = pOut_Tran;
		pOut_Tran = pOut_Proc;
		pOut_Proc = ptr;

		// start Out background transfer
		DMA_DA2SD(addrOut, pOut_Tran, hOut->width);
		addrOut += hOut->width * 2;
	}
	DMA_DA2SD(addrOut, pOut_Tran, hOut->width);
	addrOut += hOut->width * 2;

	// fill black rows
	for(i=0; i<empty_height; i++)
	{
		memset((void*)(addrOut/2), 0, hOut->width);
	}
}

//___________________________________________________________________
// Function: IMGCMC_YUYV_RGB565
// Usage: Convert color-mode of image data.
// Parameters:
//    pIn			- pointer to input
//    pOut			- pointer to output
//    size          - number of pixels to be converted
// Return Values:
//    N/A
//___________________________________________________________________
// Y,U,V: [0,255]
// R = Y                   + 1.402  *(V-128)
// G = Y - 0.34414*(U-128) - 0.71414*(V-128)
// B = Y + 1.772  *(U-128)
//
// Y <<= 8
// U,V -= 128
// chrom_r = 359 * V;
// chrom_g = -88 * U - 183 * V;
// chrom_b = 454 * U;
// (R<<8) = Y + chrom_r
// (G<<8) = Y + chrom_g
// (B<<8) = Y + chrom_b
void IMGCMC_YUYV_RGB565(WORD *pIn, WORD *pOut, WORD size)
{
	WORD i;
	WORD Y1, Y2;
	short U, V;
	long chrom_r, chrom_g, chrom_b;
	long temp;
	WORD R, G, B;

	// for each 2 pixels
	for (i=0; i<size; i+=2)
	{
		// read YUV(Y<<=8)
		// U,V is swapped due to Camera Difference.
		V = (short)(pIn[0]>>8) - 128;
		Y1 = pIn[0] << 8;
		U = (short)(pIn[1]>>8) - 128;
		Y2 = pIn[1] << 8;

		// chrominance modifier
		chrom_r = 359 * V;
		chrom_g = -88 * U - 183 * V;
		chrom_b = 454 * U;

		// R1
		temp = (long)Y1 + chrom_r;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		R = (WORD)temp;
		
		// G1
		temp = (long)Y1 + chrom_g;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		G = (WORD)temp;
		
		// B1
		temp = (long)Y1 + chrom_b;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		B = (WORD)temp;

		// pixel1
		pOut[1] = ((R&0x00F8)<<8) | ((G&0x00FC)<<3) | ((B&0x00F8)>>3);

		// R2
		temp = (long)Y2 + chrom_r;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		R = (WORD)temp;
		
		// G2
		temp = (long)Y2 + chrom_g;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		G = (WORD)temp;
		
		// B2
		temp = (long)Y2 + chrom_b;
		temp >>= 8;
		temp = (temp > 0xF0)? 0xF0 : temp;
		temp = (temp < 0x10)? 0x10 : temp;
		B = (WORD)temp;

		// pixel2
		pOut[0] = ((R&0x00F8)<<8) | ((G&0x00FC)<<3) | ((B&0x00F8)>>3);
		
		pOut += 2;
		pIn += 2;
	}
}


// the end
//////////////////////////////////////////////////////////////////////////