📄 download_filter.cpp
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/* $Id: download_filter.cpp,v 1.3 2001/09/05 19:50:26 wmay Exp $ */
/****************************************************************************/
/* MPEG4 Visual Texture Coding (VTC) Mode Software */
/* */
/* This software was jointly developed by the following participants: */
/* */
/* Single-quant, multi-quant and flow control */
/* are provided by Sarnoff Corporation */
/* Iraj Sodagar (iraj@sarnoff.com) */
/* Hung-Ju Lee (hjlee@sarnoff.com) */
/* Paul Hatrack (hatrack@sarnoff.com) */
/* Shipeng Li (shipeng@sarnoff.com) */
/* Bing-Bing Chai (bchai@sarnoff.com) */
/* B.S. Srinivas (bsrinivas@sarnoff.com) */
/* */
/* Bi-level is provided by Texas Instruments */
/* Jie Liang (liang@ti.com) */
/* */
/* Shape Coding is provided by OKI Electric Industry Co., Ltd. */
/* Zhixiong Wu (sgo@hlabs.oki.co.jp) */
/* Yoshihiro Ueda (yueda@hlabs.oki.co.jp) */
/* Toshifumi Kanamaru (kanamaru@hlabs.oki.co.jp) */
/* */
/* OKI, Sharp, Sarnoff, TI and Microsoft contributed to bitstream */
/* exchange and bug fixing. */
/* */
/* */
/* In the course of development of the MPEG-4 standard, this software */
/* module is an implementation of a part of one or more MPEG-4 tools as */
/* specified by the MPEG-4 standard. */
/* */
/* The copyright of this software belongs to ISO/IEC. ISO/IEC gives use */
/* of the MPEG-4 standard free license to use this software module or */
/* modifications thereof for hardware or software products claiming */
/* conformance to the MPEG-4 standard. */
/* */
/* Those intending to use this software module in hardware or software */
/* products are advised that use may infringe existing patents. The */
/* original developers of this software module and their companies, the */
/* subsequent editors and their companies, and ISO/IEC have no liability */
/* and ISO/IEC have no liability for use of this software module or */
/* modification thereof in an implementation. */
/* */
/* Permission is granted to MPEG members to use, copy, modify, */
/* and distribute the software modules ( or portions thereof ) */
/* for standardization activity within ISO/IEC JTC1/SC29/WG11. */
/* */
/* Copyright 1995, 1996, 1997, 1998 ISO/IEC */
/****************************************************************************/
/************************************************************/
/* Sarnoff Very Low Bit Rate Still Image Coder */
/* Copyright 1995, 1996, 1997, 1998 Sarnoff Corporation */
/************************************************************/
/************************************************************/
/* Filename: download_filter.c */
/* Author: Bing-Bing Chai */
/* Date: Jan. 30, 1998 */
/* */
/* Descriptions: */
/* This file contains the routines to up/download */
/* wavelet filters when desired. Proper conversions from */
/* Floating poInt to Int are taken care of whenever */
/* needed. */
/* */
/* It is assumed that Short and Float */
/* are 2 bytes, and 4 bytes respectively. */
/* */
/************************************************************/
#define DOWN_DEBUG 0
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include "dataStruct.hpp"
#include "startcode.hpp"
#include "dwt.h"
#include "errorHandler.hpp"
#include "msg.hpp"
#include "bitpack.hpp"
#include "download_filter.h"
Void CVTCCommon::check_marker(Int marker_bit)
{
if(marker_bit != MARKER_BIT)
errorHandler("Error in download wavelet filters\n");
}
Void CVTCCommon::check_symmetry(FILTER *filter)
{
Int i,half;
/* -------- check lowpass filter --------- */
half=filter->LPLength>>1;
if(half<<1==filter->LPLength)
filter->DWT_Class=DWT_EVEN_SYMMETRIC; /* even filter */
else
filter->DWT_Class=DWT_ODD_SYMMETRIC; /* odd filter */
for(i=0;i<half;i++)
if(filter->DWT_Type == 0){
if(((Short*)filter->LPCoeff)[i] !=
((Short*)filter->LPCoeff)[filter->LPLength-i-1])
errorHandler("Lowpass filter is not symmetric.\n");
}
else
if(((double*)filter->LPCoeff)[i] !=
((double*)filter->LPCoeff)[filter->LPLength-i-1])
errorHandler("Lowpass filter is not symmetric.\n");
/* -------- check highpass filter ---------- */
half=filter->HPLength>>1;
/* check for error */
if(half<<1==filter->HPLength && filter->DWT_Class==DWT_ODD_SYMMETRIC)
errorHandler("Lowpass filter has odd taps, while highpass filter has even"\
" taps->\n");
if(half<<1!=filter->HPLength && filter->DWT_Class==DWT_EVEN_SYMMETRIC)
errorHandler("Lowpass filter has even taps, while highpass filter has odd"\
" taps.\n");
if(filter->DWT_Class==DWT_ODD_SYMMETRIC){ /* ODD_SYMMETRIC, symmetric */
for(i=0;i<half;i++)
if(filter->DWT_Type == 0){
if(((Short*)filter->HPCoeff)[i] !=
((Short*)filter->HPCoeff)[filter->HPLength-i-1])
errorHandler("Highpass filter is not symmetric.\n");
}
else
if(((double*)filter->HPCoeff)[i] !=
((double*)filter->HPCoeff)[filter->HPLength-i-1])
errorHandler("Highpass filter is not symmetric.\n");
}
else{ /* EVEN_SYMMETRIC, antisymmetric */
for(i=0;i<half;i++)
if(filter->DWT_Type == 0){
if(((Short*)filter->HPCoeff)[i] !=-
((Short*)filter->HPCoeff)[filter->HPLength-i-1])
errorHandler("Highpass filter is not antisymmetric.\n");
}
else
if(((double*)filter->HPCoeff)[i] !=-
((double*)filter->HPCoeff)[filter->HPLength-i-1])
errorHandler("Highpass filter is not antisymmetric.\n");
}
}
Void CVTCCommon::upload_wavelet_filters(FILTER *filter)
{
Int i;
Float f;
Short s;
UShort *usptr;
UInt *uIntptr;
/* poInters to filter taps */
usptr=(UShort *)&s;
uIntptr=(UInt *)&f;
/* filter lengths */
emit_bits((UShort)filter->LPLength,4);
emit_bits((UShort)filter->HPLength,4);
/* upload lowpass filter */
for(i=0;i<filter->LPLength;i++)
if(filter->DWT_Type == DWT_INT_TYPE){
s=((Short*)(filter->LPCoeff))[i];
emit_bits(*usptr,16);
emit_bits(MARKER_BIT,1);
}
else{
f=(Float)((double *)filter->LPCoeff)[i];
emit_bits((UShort)((*uIntptr)>>16),16);
emit_bits(MARKER_BIT,1);
emit_bits((UShort)(*uIntptr),16);
emit_bits(MARKER_BIT,1);
}
/* upload highpass filter */
for(i=0;i<filter->HPLength;i++)
if(filter->DWT_Type == DWT_INT_TYPE){
s=((Short*)(filter->HPCoeff))[i];
emit_bits(*usptr,16);
emit_bits(MARKER_BIT,1);
}
else{
f=(Float)((double *)filter->HPCoeff)[i];
emit_bits((UShort)((*uIntptr)>>16),16);
emit_bits(MARKER_BIT,1);
emit_bits((UShort)(*uIntptr),16);
emit_bits(MARKER_BIT,1);
}
if(filter->DWT_Type == DWT_INT_TYPE){
emit_bits((UShort)filter->Scale,16);
emit_bits(MARKER_BIT,1); /* needed to prevent start code emulation. */
/* this is not presented in the current syntax */
}
}
Void CVTCCommon::download_wavelet_filters(FILTER **Filter, Int type)
{
Int i,marker_bit;
double *LPD=NULL, *HPD=NULL;
Short *LPS=NULL, *HPS=NULL,s;
UShort *usptr;
UInt *uIntptr;
Float f;
FILTER *filter; // hjlee 0901
usptr=(UShort *)&s;
uIntptr=(UInt *)&f;
/* hjlee 0901 */
filter = (FILTER *)malloc(sizeof(FILTER));
if(filter == NULL)
errorHandler("Memory allocation error\n");
filter->DWT_Type = (type ==0)? DWT_INT_TYPE: DWT_DBL_TYPE;
/* get filter lengths */
filter->LPLength=get_X_bits(4);
filter->HPLength=get_X_bits(4);
/* allocate memory for filters*/
if(filter->DWT_Type==DWT_INT_TYPE){
LPS=(Short *)malloc(sizeof(Short)*filter->LPLength);
HPS=(Short *)malloc(sizeof(Short)*filter->HPLength);
if(LPS==NULL || HPS==NULL)
errorHandler("Cannot allocate memory to download wavelet filters\n");
filter->LPCoeff=LPS;
filter->HPCoeff=HPS;
}
else{
LPD=(double *)malloc(sizeof(double)*filter->LPLength);
HPD=(double *)malloc(sizeof(double)*filter->HPLength);
if(LPD==NULL || HPD==NULL)
errorHandler("Cannot allocate memory to download wavelet filters\n");
filter->LPCoeff=LPD;
filter->HPCoeff=HPD;
}
/* get lowpass filter */
for(i=0;i<filter->LPLength;i++)
if(filter->DWT_Type==DWT_INT_TYPE){
*usptr=get_X_bits(16);
LPS[i]=s;
marker_bit=get_X_bits(1);
check_marker(marker_bit);
}
else{
*uIntptr=get_X_bits(16);
marker_bit=get_X_bits(1);
check_marker(marker_bit);
*uIntptr=((*uIntptr)<<16)+get_X_bits(16);
marker_bit=get_X_bits(1);
check_marker(marker_bit);
LPD[i]=f;
}
/* get highpass filter */
for(i=0;i<filter->HPLength;i++)
if(filter->DWT_Type==DWT_INT_TYPE){
*usptr=get_X_bits(16);
HPS[i]=s;
marker_bit=get_X_bits(1);
check_marker(marker_bit);
}
else{
*uIntptr=get_X_bits(16);
marker_bit=get_X_bits(1);
check_marker(marker_bit);
*uIntptr=((*uIntptr)<<16)+get_X_bits(16);
marker_bit=get_X_bits(1);
check_marker(marker_bit);
HPD[i]=f;
}
check_symmetry(filter);
if(filter->DWT_Type==DWT_INT_TYPE){
filter->Scale=get_X_bits(16);
marker_bit=get_X_bits(1);
check_marker(marker_bit);
}
}
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