jedioutcast/utils/roq2/libim/imgiflzw.c
2013-04-04 13:07:40 -05:00

1492 lines
22 KiB
C

/**
** $Header: /roq/libim/imgiflzw.c 1 11/02/99 4:38p Zaphod $
** Copyright (c) 1989-1995 San Diego Supercomputer Center (SDSC)
** a division of General Atomics, San Diego, California, USA
**
** Users and possessors of this source code are hereby granted a
** nonexclusive, royalty-free copyright and design patent license to
** use this code in individual software. License is not granted for
** commercial resale, in whole or in part, without prior written
** permission from SDSC. This source is provided "AS IS" without express
** or implied warranty of any kind.
**
** For further information contact:
** E-Mail: info@sds.sdsc.edu
**
** Surface Mail: Information Center
** San Diego Supercomputer Center
** P.O. Box 85608
** San Diego, CA 92138-5608
** (619) 534-5000
**/
#define HEADER " $Header: /roq/libim/imgiflzw.c 1 11/02/99 4:38p Zaphod $"
/**
** FILE
** imgiflzw.c - Do Lempel-Ziv & Welch uncompress/compress
**
** PROJECT
** libim - SDSC image manipulation library
**
** DESCRIPTION
** imlzw.c contains rountines for decoding and encoding bytes
** using Lempel-Ziv & Welch uncompress/compress algorithm.
**
** PUBLIC CONTENTS
** d =defined constant
** f =function
** m =defined macro
** t =typedef/struct/union
** v =variable
** ? =other
**
** imLzwCompGif f
**
** PRIVATE CONTENTS
**
** imLzwGetCode f
** imLzwError f
** imLzwGifNextPixel f
** imLzwPackBits f
**
** struct str_table_node t
** struct str_table_node t
** strTableNode t
** strTableNodePtr t
** strTable t
**
**
** IMMAX_LWZ_BITS d maximum number of bits allowed by LWZ
** IMMAXIMUMCODE d maximum code size
** IMBLOCKSIZE d maximum block byte count plus one
** IMNULLPREFIX d null prefix
**
** ImGifEasyFail m non fatal error ocurred. report the error.
**
** CODE CREDITS
** David Koblas, 1990.
** Custom development, Soraya Gonzales, Intevep S.A., Venzuela, 1991.
** Extensions, Vinh Le, San Diego Supercomputer Center, 1992.
** Extensions, Dave Nadeau, San Diego Supercomputer Center, 1993.
**
**
** HISTORY
** $Log: /roq/libim/imgiflzw.c $
*
* 1 11/02/99 4:38p Zaphod
** Revision 1.11 1995/06/29 00:28:04 bduggan
** updated copyright year
**
** Revision 1.10 1995/06/16 08:43:52 bduggan
** cleaned up code formatting
**
** Revision 1.9 1995/01/10 23:25:55 bduggan
** Updated copyright notice
**
** Revision 1.8 1994/10/03 11:29:39 nadeau
** Updated to ANSI C and C++ compatibility.
** Removed all use of register keyword.
** Minimized use of custom SDSC types (e.g., uchar vs. unsigned char)
** Changed all float arguments to double.
** Added forward declarations.
** Added misc. casts to passify SGI and DEC compilers.
** Changed all macros and defined constants to have names
** starting with IM.
** Updated comments.
** Updated indenting on some code.
** Updated copyright message.
**
** Revision 1.7 92/08/31 17:24:09 vle
** Updated copyright notice.
**
** Revision 1.6 91/10/03 09:03:23 nadeau
** Fixed #includes.
**
** Revision 1.5 91/03/21 08:51:38 nadeau
** ifdef-ed out inclusion of strings.h. Nothing seems
** to need it and it confuses the compiler on SysV vs.
** BSD machines (string.h vs. strings.h).
**
** Revision 1.4 91/03/13 17:11:53 soraya
** *** empty log message ***
**
** Revision 1.3 91/03/11 09:19:07 soraya
** Optimization and comment cleanup.
**
** Revision 1.2 91/01/31 08:34:42 soraya
** Adding comments
**
**
**
**/
#if 0
The lines between the dashes are taken directly from the file jrdgif.c:
-----------------------------------------------------------------------------
/*
* jrdgif.c
*
* Copyright (C) 1991, 1992, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains routines to read input images in GIF format.
*
* These routines may need modification for non-Unix environments or
* specialized applications. As they stand, they assume input from
* an ordinary stdio stream. They further assume that reading begins
* at the start of the file; input_init may need work if the
* user interface has already read some data (e.g., to determine that
* the file is indeed GIF format).
*
* These routines are invoked via the methods get_input_row
* and input_init/term.
*/
/*
* This code is loosely based on giftoppm from the PBMPLUS distribution
* of Feb. 1991. That file contains the following copyright notice:
* +-------------------------------------------------------------------+
* | Copyright 1990, David Koblas. |
* | Permission to use, copy, modify, and distribute this software |
* | and its documentation for any purpose and without fee is hereby |
* | granted, provided that the above copyright notice appear in all |
* | copies and that both that copyright notice and this permission |
* | notice appear in supporting documentation. This software is |
* | provided "as is" without express or implied warranty. |
* +-------------------------------------------------------------------+
*
* We are also required to state that
* "The Graphics Interchange Format(c) is the Copyright property of
* CompuServe Incorporated. GIF(sm) is a Service Mark property of
* CompuServe Incorporated."
*/
-----------------------------------------------------------------------------
#endif
/*
* imLzwGetCode
* imLzwReadByte
*
* Gif Image decompression - from LZW to Gif
* Written by David Koblas.
* Copyright 1989
* Modified by Soraya Gonzalez
* San Diego Supercomputer Center
* to include it in the image library
* ==================================================================
* imLzwError
* imLzwGifNextPixel
* imLzwPackBits
* imLzwCompGif
*
*
* GIF Image compression - LZW algorithm implemented with Trie type
* structure.
* Written by Bailey Brown, Jr.
* last change May 24, 1990
* Modified by Soraya Gonzalez.
* San Diego Supercomputer Center.
* December 1990
* to include it in the image library
*
*
*/
#ifdef USE_STDLIB_H
#include <stdlib.h>
#else
#ifdef old
#ifdef USE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#endif
#endif /* USE_STDLIB_H */
#include "iminternal.h"
/*
* TYPEDEF & STRUCTURE
* struct str_table_node
* struct str_table_node
* strTableNode
* strTableNodePtr
* strTable
* DESCRIPTION
*
*/
typedef struct str_table_entry {
int code;
int prefix;
int suffix;
} strTableEntry;
typedef struct str_table_node {
strTableEntry entry;
struct str_table_node *left;
struct str_table_node *right;
struct str_table_node *children;
} strTableNode, *strTableNodePtr, **strTable;
/*
* CONSTANTS
*
* IMMAX_LWZ_BITS - maximum number of bits allowed by LWZ
* IMMAXIMUMCODE - maximum code size
* IMBLOCKSIZE - maximum block byte count plus one
* IMNULLPREFIX - null prefix
*/
#define IMMAX_LWZ_BITS 12
#define IMMAXIMUMCODE 4095 /* 2**maximum_code_size */
#define IMBLOCKSIZE 256 /* max block byte count + 1 */
#define IMNULLPREFIX -1
/*
* MACROS
* ImGifEasyFail - non fatal error occurred. report the error.
*/
#define ImGifEasyFail(str,status) \
{ \
ImErrorWarning(str,status,IMEUNKNOWN); \
return(status); \
}
/*
* FILE-WIDE VARIABLE
*/
static int RasterIndex; /* index over the rasterdata array */
/*
* FUNCTION
* imLzwGetCode - return the next code from the input stream.
*
* DESCRIPTION
* return the next code from the input stream. The code read
* has code_size size. flag is used to initialize
* the internal variables.
*/
static int
#ifdef __STDC__
imLzwGetCode(int ioType, int fd, FILE *fp, int code_size, int flag)
#else
imLzwGetCode(ioType, fd, fp, code_size, flag)
int ioType; /* I/O flags */
int fd; /* Input file descriptor */
FILE *fp; /* Input file pointer */
int code_size; /* current code size used */
int flag; /* used for to initializations */
#endif
{
static unsigned char buf[280];
static int curbit,lastbit,done,last_byte;
int i, j, ret;
unsigned char count;
if (flag)
{
curbit = 0;
lastbit = 0;
done = FALSE;
return 0;
}
if ( (curbit+code_size) >= lastbit)
{
if (done)
if (curbit>=lastbit)
ImGifEasyFail("Ran off the end of my bits",-1);
buf[0] = buf[last_byte-2];
buf[1] = buf[last_byte-1];
if ( ImBinRead( ioType,fd,fp,&count, UCHAR, 1, 1 ) == -1 )
ImReturnBinError( );
if (count == 0)
done = TRUE;
else if ( ImBinRead( ioType,fd,fp,&buf[2],UCHAR,1,count ) == -1 )
ImReturnBinError( );
last_byte = 2 + count;
curbit = (curbit - lastbit) + 16;
lastbit = (2+count)*8 ;
}
ret = 0;
for( i = curbit, j = 0; j < code_size; i++, j++ )
ret |= ((buf[ i / 8 ] & (1 << (i % 8))) != 0) << j;
curbit += code_size;
return ret;
}
/*
* FUNCTION
* ImLzwReadByte - return the next decoded pixel
*
* DESCRIPTION
* Return the next decoded pixel value.
*/
int
#ifdef __STDC__
imLzwReadByte(int ioType,int fd,FILE *fp,int flag,int input_code_size)
#else
imLzwReadByte(ioType,fd,fp,flag,input_code_size)
int ioType; /* I/O flags */
int fd; /* Input file descriptor */
FILE *fp; /* Input file pointer */
int flag; /* to make intializations*/
int input_code_size;/* code size */
#endif
{
static int fresh=FALSE;
int code,incode;
unsigned char count,junk;
static int code_size,set_code_size;
static int max_code,max_code_size;
static int firstcode,oldcode;
static int clear_code,end_code;
static int table[2][(1<< IMMAX_LWZ_BITS)];
static int stack[(1<<(IMMAX_LWZ_BITS))*2],*sp;
int i;
if (flag)
{
set_code_size = input_code_size;
code_size = set_code_size+1;
clear_code = 1 << set_code_size ;
end_code = clear_code + 1;
max_code_size = 2*clear_code;
max_code = clear_code+2;
imLzwGetCode(ioType,fd,fp,NULL,TRUE);
fresh=TRUE;
for (i=0;i<clear_code;i++)
{
table[0][i] = 0;
table[1][i] = i;
}
for (;i<(1<<IMMAX_LWZ_BITS);i++)
table[0][i] = table[1][0] = 0;
sp = stack;
return 0;
}
else
if (fresh)
{
fresh = FALSE;
do
{
firstcode=oldcode=
imLzwGetCode(ioType,fd,fp, code_size, FALSE);
} while (firstcode == clear_code);
return firstcode;
}
if (sp > stack)
return *--sp;
while ((code=imLzwGetCode(ioType,fd,fp,code_size,FALSE))>=0)
{
if (code == clear_code)
{
for (i=0;i<clear_code;i++)
{
table[0][i] = 0;
table[1][i] = i;
}
for (;i<(1<<IMMAX_LWZ_BITS);i++)
table[0][i] = table[1][i] = 0;
code_size = set_code_size+1;
max_code_size = 2*clear_code;
max_code = clear_code+2;
sp = stack;
firstcode=oldcode=
imLzwGetCode(ioType,fd,fp,code_size,FALSE);
return firstcode;
}
else
if (code == end_code)
{
while ( ImBinRead(ioType,fd,fp,&count,UCHAR,1,1) != -1 && (count!=0))
while (count-->0 && ImBinRead( ioType,fd,fp,&junk,UCHAR,1,1) != -1);
if (count!=0)
ImGifEasyFail("Missing EOD in data stream (common occurance)",-1);
return -1;
}
incode = code;
if (code >= max_code)
{
*sp++ = firstcode;
code = oldcode;
}
while (code >= clear_code)
{
*sp++ = table[1][code];
if (code == table[0][code])
ImGifEasyFail("Circular table entry BIG ERROR",-1);
code = table[0][code];
}
*sp++ = firstcode = table[1][code];
if ((code=max_code)<(1<<IMMAX_LWZ_BITS))
{
table[0][code] = oldcode;
table[1][code] = firstcode;
max_code++;
if ((max_code >= max_code_size) &&
(max_code_size < (1<<IMMAX_LWZ_BITS)))
{
max_code_size *= 2;
code_size++;
}
}
oldcode = incode;
if (sp > stack)
return *--sp;
}
return code;
}
/*
* FUNCTION
* ImLzwError - prints the error ocurred in the standar error file
* and return with status equal to -1
*/
static int
#ifdef __STDC__
imLzwError(char *s)
#else
imLzwError(s)
char *s;
#endif
{
ImErrorFatal(s, -1, IMEUNKNOWN);
}
/*
* FUNCTION
* ImLzwGifNextPixel - Return the next pixel from the raster data
*
* DESCRIPTION
* The pixel values are stored in the rasterdata buffer. This
* function returns the next pixel value.
*/
static int
#ifdef __STDC__
imLzwGifNextPixel(unsigned char *rasterdata,int size)
#else
imLzwGifNextPixel( rasterdata,size)
unsigned char *rasterdata;
int size;
#endif
{
if ( RasterIndex == size )
return (EOF);
return( rasterdata[RasterIndex++] );
}
/*
* FUNCTION
* imLzwPackBits - packs the bits of the codes generated
* by imLzwCompGif.
* DESCRIPTION
* imLzwPackBits() packs the bits of the codes generated by ImLzwCompGif
* into a 1..256 byte output block. The first byte of the block is the
* number 0..255 of data bytes in the block. To flush or initialize
* the block, pass a negative argument.
*/
static int
#ifdef __STDC__
imLzwPackBits(int compress_size, int prefix, int ioType, int fd, FILE *fp)
#else
imLzwPackBits(compress_size, prefix, ioType, fd, fp)
int compress_size;
int prefix;
int ioType;
int fd;
FILE *fp;
#endif
{
static int cur_bit = 8;
static unsigned char block[IMBLOCKSIZE] = { 0 };
int i, left_over_bits;
/* if we are about to excede the bounds of block or if the flush
code (code_bis < 0) we output the block */
if((cur_bit + compress_size > (IMBLOCKSIZE-1)*8) || (prefix < 0))
{
/* handle case of data overlapping blocks */
if ((left_over_bits = (((cur_bit>>3) +
((cur_bit & 7) != 0))<<3) - cur_bit) != 0)
{
for (i=0; i < left_over_bits; i++)
{
if (prefix & (1<<i))
block[cur_bit>>3] |= (char)(1<<(cur_bit & 7));
/* note n>>3 == n/8 and n & 7 == n % 8 */
cur_bit++;
}
}
compress_size -= left_over_bits;
prefix = prefix>>left_over_bits;
block[0] = (unsigned char)((cur_bit>>3) - 1);
if (block[0])
if ( ImBinWrite( ioType, fd, fp, block, UCHAR, 1, block[0]+1) == -1)
ImReturnBinError();
for(i=0; i < IMBLOCKSIZE; i++)
block[i] = 0;
cur_bit = 8;
}
if (prefix >= 0)
{
for (i=0; i < compress_size; i++)
{
if (prefix & (1<<i))
block[cur_bit>>3] |= (unsigned char)(1<<(cur_bit & 7));
/* note n>>3 == n/8 and n & 7 == n % 8 */
cur_bit++;
}
}
return (1);
}
/*
* FUNCTION
* ImLzwCompGif - compresses and pack the pixels values that are
* stored in rasterdata buffer using the
* LZW algorithm.
* DESCRIPTION
* ImLzwCompGif () recieves pointers to a buffer and an output
* stream, and the code size as parameters and outputs successive
* blocks of LZW compressed gif data. The calling routine should
* have aready written the GIF file header out to the output file.
* It assumes that there will be no more than 8 bits/pixel and that
* each data item comes from successive bytes returned by
* ImLzwGifNextPixel().
*/
int
#ifdef __STDC__
imLzwCompGif(int ioType,int fd,FILE *fp,int code_size, unsigned char *rasterdata, int size)
#else
imLzwCompGif(ioType,fd,fp,code_size, rasterdata, size)
int ioType; /* I/O flags */
int fd; /* Input file descriptor */
FILE *fp; /* Input file pointer */
int code_size; /* i.e. for 8 bits/pixel code_size = 9; */
unsigned char *rasterdata; /* rasterdata to be compress */
int size; /* size of the raster data */
#endif
{
strTable heap; /* our very own memory manager */
int heap_index;
int clear_code, end_code, cur_code;
int i, found, num_colors, prefix, compress_size;
int cur_char, end_of_data, bits_per_pix;
strTableNodePtr cur_node;
strTable root; /* root of string table for LZW compression */
/* is an array of 2**bits_per_pix pointers
to atomic nodes */
heap_index = 0;
heap = (strTable)malloc(sizeof(strTableNodePtr)*IMMAXIMUMCODE);
if (heap == NULL)
imLzwError("can't allocate heap");
for (i=0; i < IMMAXIMUMCODE; i++)
{
heap[i] = (strTableNodePtr)malloc(sizeof(strTableNode));
if (heap[i] == NULL)
imLzwError("can't allocate heap");
}
bits_per_pix = code_size - 1;
compress_size = code_size;
num_colors = 1<<(bits_per_pix);
clear_code = num_colors;
end_code = clear_code + 1;
cur_code = end_code + 1;
RasterIndex = 0;
prefix = IMNULLPREFIX;
root = (strTable)malloc(sizeof(strTableNodePtr)*num_colors);
if (!root)
imLzwError("memory allocation failure (root)");
for(i=0; i<num_colors; i++)
{
root[i] = heap[heap_index++];
root[i]->entry.code = i;
root[i]->entry.prefix = IMNULLPREFIX;
root[i]->entry.suffix = i;
root[i]->left = NULL;
root[i]->right = NULL;
root[i]->children = NULL;
}
/* initialize output block */
imLzwPackBits(compress_size, -1, ioType,fd,fp);
imLzwPackBits(compress_size, clear_code, ioType,fd,fp);
end_of_data = 0;
if ((cur_char = imLzwGifNextPixel(rasterdata,size)) == EOF)
imLzwError("premature end of data");
while (!end_of_data)
{
prefix = cur_char;
cur_node = root[prefix];
found = 1;
if ((cur_char = imLzwGifNextPixel(rasterdata,size)) == EOF)
{
end_of_data = 1;
break;
}
while(cur_node->children && found)
{
cur_node = cur_node->children;
while(cur_node->entry.suffix != cur_char)
{
if (cur_char < cur_node->entry.suffix)
{
if (cur_node->left)
cur_node = cur_node->left;
else
{
cur_node->left = heap[heap_index++];
cur_node = cur_node->left;
found = 0;
break;
}
}
else
{
if (cur_node->right)
cur_node = cur_node->right;
else
{
cur_node->right = heap[heap_index++];
cur_node = cur_node->right;
found = 0;
break;
}
}
}
if (found)
{
prefix = cur_node->entry.code;
if((cur_char = imLzwGifNextPixel(rasterdata,size)) == EOF)
{
end_of_data = 1;
break;
}
}
}
if (end_of_data)
break;
if (found)
{
cur_node->children = heap[heap_index++];
cur_node = cur_node->children;
}
cur_node->children = NULL;
cur_node->left = NULL;
cur_node->right = NULL;
cur_node->entry.code = cur_code;
cur_node->entry.prefix = prefix;
cur_node->entry.suffix = cur_char;
imLzwPackBits(compress_size, prefix, ioType,fd,fp);
if (cur_code > ((1<<(compress_size))-1))
compress_size++;
if (cur_code < IMMAXIMUMCODE)
{
cur_code++;
}
else
{
heap_index = num_colors; /* reinitialize string table */
for (i=0; i < num_colors; i++ )
root[i]->children = NULL;
imLzwPackBits(compress_size, clear_code, ioType,fd,fp);
compress_size = bits_per_pix + 1;
cur_code = end_code + 1;
}
}
imLzwPackBits(compress_size, prefix, ioType,fd,fp);
imLzwPackBits(compress_size, end_code, ioType,fd,fp);
imLzwPackBits(compress_size, -1, ioType,fd,fp);
for (i=0; i < IMMAXIMUMCODE; i++)
free(heap[i]);
free(heap);
free(root);
return (1);
}