📄 bitpack.cpp
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/* $Id: bitpack.c,v 1.35 1998/05/19 15:27:19 hjlee 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: bitpack.c */
/* Author: Bing-Bing CHai */
/* Date: Dec. 24, 1997 */
/* */
/* Descriptions: */
/* This file contains the functions to read and write */
/* to files. Most of the functions are the sames as */
/* that are used in older version of MZTE. */
/* */
/* The following functions have been created or */
/* modified. */
/* Void init_bit_packing_fp(File *fp) */
/* Int nextinputbit() */
/* Int get_bit_rate() */
/* Void restore_arithmetic_offset(Int bits_to_go) */
/************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include "basic.hpp"
#include "dataStruct.hpp"
#include "bitpack.hpp"
//#include "PEZW_zerotree.h"
//#include "wvtPEZW.h"
#include "msg.hpp"
#include "errorHandler.hpp"
#define BUFFER_SIZE 1024
#define EXTRABYTES 8 // hjlee 0901
#define MAXLOOKBITS (EXTRABYTES*8) // hjlee 0901
static bytes_in_buffer=0, huff_put_buffer=0, huff_put_bits=0,
byte_ptr=0,buffer_length=0,totalBitRate=0;
static Int bit_num = -1; /* signal to start */
static UInt bit_buf = 0;
static UChar output_buffer[BUFFER_SIZE];
static FILE *bitfile;
static Int byte_count=0;
static Int count, junkCount;
static Int zerocount=0;
/****************************************************************/
/* Intilization of file poInter, must be called prior to using */
/* any function in this file. By Bing-Bing Chai */
/****************************************************************/
Void CVTCCommon::init_bit_packing_fp(FILE *fp, Int clearByte)
{
byte_count=0;
/*count=0;*/
bitfile=fp;
bytes_in_buffer=huff_put_buffer=huff_put_bits=bit_buf=0;
/* clean byte poInter only when asked for */
if(clearByte == 0)
fseek(bitfile,-(buffer_length-byte_ptr+((bit_num+1)/8)),SEEK_CUR);
buffer_length=byte_ptr=0;
bit_num=-1;
}
/**********************************/
/* return total bit rate in bits */
/**********************************/
Int CVTCEncoder::get_total_bit_rate()
{
return (totalBitRate);
}
Int CVTCEncoder::get_total_bit_rate_dec()
{
return (count);
}
Int CVTCEncoder::get_total_bit_rate_junk()
{
return (junkCount);
}
/****************************************************************/
/****************** utilities for bit packing *****************/
/****************************************************************/
/* put a byte on the bit stream */
#define emit_byte(val) \
if (bytes_in_buffer >= BUFFER_SIZE) \
flush_bytes1(); \
output_buffer[bytes_in_buffer++] = (UChar) (val)
/* Outputting bytes to the file */
Void CVTCCommon::flush_bytes1()
{
if (bytes_in_buffer) {
fwrite(output_buffer, bytes_in_buffer, sizeof(UChar), bitfile);
}
bytes_in_buffer = 0;
}
/* Outputting bytes to the file and count the last few bits, used by main.c */
Void CVTCEncoder::flush_bytes()
{
if (bytes_in_buffer) {
fwrite(output_buffer, bytes_in_buffer, sizeof(UChar), bitfile);
totalBitRate +=8-totalBitRate%8;
}
bytes_in_buffer = 0;
}
Void CVTCCommon::emit_bits(UShort code, Int size)
{
register UInt put_buffer = code;
register Int put_bits = huff_put_bits;
Int c;
if (size == 0) {
return;
}
totalBitRate +=size;
/* Mask off any excess bits in code */
put_buffer &= (((Int)1) << size) - 1;
/* new number of bits in buffer */
put_bits += size;
/* align incoming bits */
put_buffer <<= 24 - put_bits;
/* and merge with old buffer contents */
put_buffer |= huff_put_buffer;
while (put_bits >= 8) {
c = (Int) ((put_buffer >> 16) & 0xFF);
emit_byte(c);
put_buffer <<= 8;
put_bits -= 8;
}
huff_put_buffer = put_buffer; /* Update global variables */
huff_put_bits = put_bits;
}
/* modified by Jie Liang (Texas Instruments)
to return the last bits left in the last byte */
Void CVTCEncoder::flush_bits1 ()
{
Int i;
if((i=huff_put_bits%8)==0)
return;
emit_bits((UShort) 0x7F, 8-i); /* fill any partial byte with ones */
huff_put_buffer = 0; /* and reset bit-buffer to empty */
huff_put_bits = 0;
}
Void CVTCEncoder::flush_bits ()
{
Int i=(huff_put_bits%8);
UShort usflush;
usflush = (0x7F >> i);
emit_bits(usflush, 8-i); /* fill any partial byte with ones */
huff_put_buffer = 0; /* and reset bit-buffer to empty */
huff_put_bits = 0;
}
Void CVTCEncoder::flush_bits_zeros ()
{
Int i;
if((i=huff_put_bits%8)==0)
return;
emit_bits((UShort) 0, 8-i); /* fill any partial byte with ones */
huff_put_buffer = 0; /* and reset bit-buffer to empty */
huff_put_bits = 0;
}
/*********************************************************/
/* put a parameter Into the file, refer to VTC syntax */
/* for algorithm */
/*********************************************************/
Int CVTCEncoder::put_param(Int value, Int nbits)
{
Int extension;
Int module = 1 << nbits;
Int mask = (1 << nbits) - 1;
Int put_bits = 0;
while (value/module > 0) {
extension = 1;
emit_bits( ((value%module) | (extension << nbits)), nbits+1);
value = value >> nbits;
put_bits += nbits+1;
}
extension = 0;
emit_bits( ((value & mask) | (extension << nbits)), nbits+1);
put_bits += nbits+1;
return (put_bits);
}
/********************************************************/
/*********** Utilities for bit unpacking **************/
/********************************************************/
/*********************************************************/
/* Get the next bit from a file */
/* Modified to read in 1000 bytes Into a buffer at a */
/* time. */
/*********************************************************/
Int CVTCCommon::nextinputbit()
{
Int v;
if (bit_num < 7) {
if(buffer_length==byte_ptr){
if((buffer_length=fread(output_buffer,1,BUFFER_SIZE,bitfile)) ==0){
/* fprintf(stderr,"out of source "); */
output_buffer[0]=0;
buffer_length++;
}
if(buffer_length==BUFFER_SIZE){
buffer_length -=EXTRABYTES;
fseek(bitfile,-EXTRABYTES,SEEK_CUR);
}
byte_ptr=0;
byte_count+=buffer_length;
}
bit_buf = (bit_buf << 8) + output_buffer[byte_ptr++];
bit_num += 8;
}
v = (bit_buf >> bit_num) & 0x00001;
bit_num--;
count++;
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