tmndec.cpp

这个程序有PC的服务端和Pocket PC上的客户端两个部分。服务端运行时

////////////////////////////////////////////////////////////////////////////
//
//
//    Project     : VideoNet version 1.1.
//    Description : Peer to Peer Video Conferencing over the LAN.
//	  Author      :	Nagareshwar Y Talekar ( [e-mail])
//    Date        : 15-6-2004.
//
//    This is the modified version of tmndecode (H.263 decoder) 
//    written by Karl & Robert.It was in ANSI C. I have converted into C++
//    so that it can be integrated into any windows application. I have 
//    removed some of the files which had display and file storing 
//    functions.I have removed the unnecessary code and also added some
//    new files..
//	  Original library dealt with files. Input & Output , both were files.
//    I have done some major changes so that it can be used for real time 
//    decoding process. Now one can use this library for decoding H263 frames. 
//
//
//    File description : 
//    Name    : Tmndec.cpp
//    Details : Main entry point for decoder.
//
//    Usage : 
//			1) InitH263Decoder
//			2) Invoke DecompressFrame with parameters
//			      compressed data and output data pointers.
//			  Note > Output data must be large enough to hold RGB data.
//                 > Change the DecompressFrame function if you want 
//					 output in YUV420 format only. Just comment out conversion routine
//          3) Repeat the step 2 for each compressed frame , for exit do 4
//			4) ExitH263Decoder  .
//
/////////////////////////////////////////////////////////////////////////////



/************************************************************************
 *
 *  tmndec.c, main(), initialization, options for tmndecode (H.263 decoder)
 *  Copyright (C) 1996  Telenor R&D, Norway
 *        Karl Olav Lillevold <[e-mail]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  Karl Olav Lillevold               <[e-mail]>
 *  Telenor Research and Development
 *  P.O.Box 83                        tel.:   [phone]
 *  N-2007 Kjeller, Norway            fax.:   [phone]
 *
 *  Robert Danielsen                  e-mail: [e-mail]
 *  Telenor Research and Development  www:    http://www.nta.no/brukere/DVC/
 *  P.O.Box 83                        tel.:   [phone]
 *  N-2007 Kjeller, Norway            fax.:   [phone]
 *  
 ************************************************************************/

/*
 * based on mpeg2decode, (C) 1994, MPEG Software Simulation Group
 * and mpeg2play, (C) 1994 Stefan Eckart
 *                         <[e-mail]>
 *
 */

#include "stdafx.h"
#include "tmndec.h"


void InitH263Decoder()
{
 
    // Open log file
	dlog=NULL;//fopen("decoder.log","w");
	
	if(dlog==NULL)
	{
	trace=0;
	quiet=1;
	verbose=0;
	}

     framerate=0;  // not used...
     outtype=0;    // YUV 
	 temp_ref = 0;
     prev_temp_ref= -1; 


     ld = &base; 
     
     initbits();    // Setup source buffer pointers
	 InitConvertTable();
     
 	 
	// For debugging....	 
	// trace=1;		// trace output
	// quiet=0;       // don't keep quiet print mesgs
	 
}



/**
*    Decompress the frame.....
*    > After decompression 
*    > yp ,up and vp pointers will point to respective Y , U , V frames...
*  
*  Input 
*      cdata    compressed data
*      size     size of the compressed frame
*      outdata  pointer to rgb buffer (size must be enough to store data)  
*  
*  Output
*      return 1  success  , outdata contains rgbdata
*	   return 0  operation failed...
*/

int DecompressFrame(unsigned char *cdata,int size,unsigned char *outdata,int outsize)
{
	static int first=1,framenum=0;
	
	//Initialize output pointers...
	yp=NULL;
	up=NULL;
	vp=NULL;

		// Copy to other buffer can be done...
		// So that source buffer will be free
		 
		cindex=0;       // index into the cframe....
		csize=size;     // size of compressed frame 
		cframe=cdata;   // pointer to compressed frme
		//memcpy(cframe,cdata,size);


		// Reset the pointers...
		initbits();

		// Get the frame header
		getheader();

	
		// If first time...then call initdecoder....
		// This has to be done after calling getheader()
		// because getheader() setup some variables using the information
		// from header...

		if (first) 
		{
		   initdecoder();
		   first = 0;
		}

    

		// Decompress the frame and get the picture frame in YUV format
		getpicture(&framenum);
    
		framenum++;

		if(yp==NULL || up==NULL || vp==NULL)
		{
			if(trace)
			fputs("decompression failed...",dlog);
		
			return  0;
		}


   		// convert YUV to RGB
		// *******  TODO *********
		// check if outdata is enough to store rgb data
		//
		int totalsize=horizontal_size * vertical_size *3;
		if(outsize< totalsize || outdata==NULL)
		{
			if(dlog)
			fputs("Output buffer is not sufficient",dlog);
		return 0;			
		}

		ConvertYUV2RGB(yp,up,vp,outdata,horizontal_size,vertical_size);
 
return 1;
}



/**
*    Do the clean up here
*
*/
void ExitH263Decoder()
{
int i;
    
for(i=0;i<3;i++)
{

	if(refframe[i])
	free(refframe[i]);

	if(oldrefframe[i])
	free(oldrefframe[i]);

	if(bframe[i])
	free(bframe[i]);

	if(edgeframeorig[i])
	free(edgeframeorig[i]);
		  	  

}	

	// close all files...
	if(dlog)
	fclose(dlog);

}



/**
*    Initialize decoder
*
*
*/
void initdecoder()
{
  int i, cc, size;


  /* clip table */
  if (!(clp=(unsigned char *)malloc(1024)))
    error("malloc failed\n");

  clp += 384;

  for (i=-384; i<640; i++)
    clp[i] = (i<0) ? 0 : ((i>255) ? 255 : i);

  /* MPEG-1 = TMN parameters */
  matrix_coefficients = 5;


  switch (source_format) 
  {
  
	case (SF_SQCIF):
      horizontal_size = 128;
      vertical_size = 96;
      break;
    case (SF_QCIF):
      horizontal_size = 176;
      vertical_size = 144;
      break;
    case (SF_CIF):
      horizontal_size = 352;
      vertical_size = 288;
      break;
    case (SF_4CIF):
      horizontal_size = 704;
      vertical_size = 576;
      break;
    case (SF_16CIF):
      horizontal_size = 1408;
      vertical_size = 1152;
      break;
    default:
      if(trace)
	  fputs("ERROR: Illegal input format\n",dlog);
      return;
      break;
  }


  mb_width = horizontal_size/16;
  mb_height = vertical_size/16;
  coded_picture_width = horizontal_size;
  coded_picture_height = vertical_size;
  chrom_width =  coded_picture_width>>1;
  chrom_height = coded_picture_height>>1;
  blk_cnt = 6;

  for (cc=0; cc<3; cc++) 
  
  {
  
	// Find out size...
	 if (cc==0)
      size = coded_picture_width*coded_picture_height;
    else
      size = chrom_width*chrom_height;


	// Allocate memory
    if (!(refframe[cc] = (unsigned char *)malloc(size)))
      error("malloc failed\n");


    if (!(oldrefframe[cc] = (unsigned char *)malloc(size)))
      error("malloc failed\n");

    if (!(bframe[cc] = (unsigned char *)malloc(size)))
      error("malloc failed\n");
  }

  for (cc=0; cc<3; cc++) 
  {
  
	  if (cc==0) 
	  {
		  size = (coded_picture_width+64)*(coded_picture_height+64);
      
		  if (!(edgeframeorig[cc] = (unsigned char *)malloc(size)))
		  error("malloc failed\n");
      
		  
		  edgeframe[cc] = edgeframeorig[cc] + (coded_picture_width+64) * 32 + 32;
	  }
      else 
	  {
      size = (chrom_width+32)*(chrom_height+32);
      
	  if (!(edgeframeorig[cc] = (unsigned char *)malloc(size)))
      error("malloc failed\n");
      
	  edgeframe[cc] = edgeframeorig[cc] + (chrom_width+32) * 16 + 16;
	  }
    
  }

  
  /* IDCT */
  if (refidct)
    init_idctref();
  else
    init_idct();
}


// Error routine......
void error(char *text)
{
	if(dlog)
	fputs(text,dlog);
}


/* trace output */
void printbits(int code,int bits,int len)
{
  
   if(dlog) 
   fputs("printbits : remove comment..!!!",dlog);

  // for (i=0; i<len; i++)
  // printf("%d",(code>>(bits-1-i))&1);
}