www.gusucode.com > 一个可以在局域网进行视频聊天的源代码 > 一个可以在局域网进行视频聊天的源代码/VoIP/decoder/Tmndec.cpp
////////////////////////////////////////////////////////////////////////////
//
//
// Project : VideoNet version 1.1.
// Description : Peer to Peer Video Conferencing over the LAN.
// Author : Nagareshwar Y Talekar ( nsry2002@yahoo.co.in)
// 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 <Karl.Lillevold@nta.no>
*
* 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 <Karl.Lillevold@nta.no>
* Telenor Research and Development
* P.O.Box 83 tel.: +47 63 84 84 00
* N-2007 Kjeller, Norway fax.: +47 63 81 00 76
*
* Robert Danielsen e-mail: Robert.Danielsen@nta.no
* Telenor Research and Development www: http://www.nta.no/brukere/DVC/
* P.O.Box 83 tel.: +47 63 84 84 00
* N-2007 Kjeller, Norway fax.: +47 63 81 00 76
*
************************************************************************/
/*
* based on mpeg2decode, (C) 1994, MPEG Software Simulation Group
* and mpeg2play, (C) 1994 Stefan Eckart
* <stefan@lis.e-technik.tu-muenchen.de>
*
*/
#include "tmndec.h"
void InitH263Decoder()
{
// Open log file
dlog=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);
}