/tags/Root-branch-php-utl/SWIG/Examples/GIFPlot/Lib/gif.c
C | 668 lines | 346 code | 119 blank | 203 comment | 52 complexity | e08ae7c2a38e812105b59d5fe8dd8ec1 MD5 | raw file
Possible License(s): LGPL-2.1, Cube, GPL-3.0, 0BSD, GPL-2.0
- /**********************************************************************
- * GIFPlot 0.0
- *
- * Dave Beazley
- *
- * Department of Computer Science Theoretical Division (T-11)
- * University of Utah Los Alamos National Laboratory
- * Salt Lake City, Utah 84112 Los Alamos, New Mexico 87545
- * beazley@cs.utah.edu beazley@lanl.gov
- *
- * Copyright (c) 1996
- * The Regents of the University of California and the University of Utah
- * All Rights Reserved
- *
- * Permission is hereby granted, without written agreement and without
- * license or royalty fees, to use, copy, modify, and distribute this
- * software and its documentation for any purpose, provided that
- * (1) The above copyright notice and the following two paragraphs
- * appear in all copies of the source code and (2) redistributions
- * including binaries reproduces these notices in the supporting
- * documentation. Substantial modifications to this software may be
- * copyrighted by their authors and need not follow the licensing terms
- * described here, provided that the new terms are clearly indicated in
- * all files where they apply.
- *
- * IN NO EVENT SHALL THE AUTHOR, THE UNIVERSITY OF CALIFORNIA, THE
- * UNIVERSITY OF UTAH OR DISTRIBUTORS OF THIS SOFTWARE BE LIABLE TO ANY
- * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
- * DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION,
- * EVEN IF THE AUTHORS OR ANY OF THE ABOVE PARTIES HAVE BEEN ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- *
- * THE AUTHOR, THE UNIVERSITY OF CALIFORNIA, AND THE UNIVERSITY OF UTAH
- * SPECIFICALLY DISCLAIM ANY WARRANTIES,INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND
- * THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE MAINTENANCE,
- * SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
- *
- **************************************************************************/
- /*******************************************************************
- * Creates a GIF format file.
- *
- * Dave Beazley (T-11)
- * August 11, 1995
- *
- * Rather than writing directly to files, this module fills out
- * output buffer.
- *
- * Note : To save memory, this routine uses approximately 50K of the
- * output buffer as temporary storage (for hash tables and compression codes).
- * The remainder of the output buffer is used to store the final image.
- * This feature allows GIF images to be created with no additional
- * memory overhead.
- *
- * -- Revision History
- * $Log$
- * Revision 1.2 2003/09/01 16:23:31 beazley
- * Restored the 'mojo'.
- *
- * Revision 1.2 1996/09/25 22:39:30 dmb
- * Fixed prototypes and use of void pointers for compatibility with the Cray T3D
- *
- * Revision 1.1 1996/09/10 17:44:00 dmb
- * Initial revision
- *
- * Revision 1.2 1995/08/31 14:46:07 beazley
- * Minor changes to support comments and a few bug fixes.
- *
- *
- ******************************************************************/
- /*
- * xvgifwr.c - handles writing of GIF files. based on flgife.c and
- * flgifc.c from the FBM Library, by Michael Maudlin
- *
- * Contains:
- * WriteGIF(fp, pic, ptype, w, h, rmap, gmap, bmap, numcols, colorstyle,
- * comment)
- *
- * Note: slightly brain-damaged, in that it'll only write non-interlaced
- * GIF files (in the interests of speed, or something)
- *
- */
- /*****************************************************************
- * Portions of this code Copyright (C) 1989 by Michael Mauldin.
- * Permission is granted to use this file in whole or in
- * part for any purpose, educational, recreational or commercial,
- * provided that this copyright notice is retained unchanged.
- * This software is available to all free of charge by anonymous
- * FTP and in the UUNET archives.
- *
- *
- * Authors: Michael Mauldin (mlm@cs.cmu.edu)
- * David Rowley (mgardi@watdcsu.waterloo.edu)
- *
- * Based on: compress.c - File compression ala IEEE Computer, June 1984.
- *
- * Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
- * Jim McKie (decvax!mcvax!jim)
- * Steve Davies (decvax!vax135!petsd!peora!srd)
- * Ken Turkowski (decvax!decwrl!turtlevax!ken)
- * James A. Woods (decvax!ihnp4!ames!jaw)
- * Joe Orost (decvax!vax135!petsd!joe)
- *****************************************************************/
- #include "gifplot.h"
- #include <string.h>
- typedef long int count_int;
- typedef unsigned char byte;
- static int gif_error;
- static unsigned char *op;
- static int Width, Height;
- static int curx, cury;
- static int Interlace;
- static void putgifword(int);
- static void compress(int, byte **, int);
- static void output_GIF(int);
- static void cl_block(void);
- static void cl_hash(count_int);
- static void char_init(void);
- static void char_out(int);
- static void flush_char(void);
- static void *OutBuffer;
- static int OutBufSize;
- static FrameBuffer *GIF_frame;
- static unsigned char pc2nc[256],r1[256],g1[256],b1[256];
- /*************************************************************/
- int FrameBuffer_makeGIF(FrameBuffer *f, ColorMap *c, void *outbuffer, unsigned int outbufsize)
- {
- int RWidth, RHeight;
- int LeftOfs, TopOfs;
- int ColorMapSize, InitCodeSize, Background, BitsPerPixel;
- int i,j,nc;
- char *rmap, *gmap, *bmap;
- char *cmap;
- int count;
- Interlace = 0;
- Background = 0;
- OutBuffer = outbuffer;
- OutBufSize = outbufsize;
- GIF_frame = f;
- cmap = (char *) c->cmap;
-
- op = (unsigned char *) outbuffer;
- gif_error = 0;
- for (i=0; i<256; i++) { pc2nc[i] = r1[i] = g1[i] = b1[i] = 0; }
- /* compute number of unique colors */
- nc = 0;
- rmap = &cmap[0];
- gmap = &cmap[256];
- bmap = &cmap[512];
- for (i=0; i<256; i++) {
- /* see if color #i is already used */
- for (j=0; j<i; j++) {
- if (rmap[i] == rmap[j] && gmap[i] == gmap[j] &&
- bmap[i] == bmap[j]) break;
- }
- if (j==i) { /* wasn't found */
- pc2nc[i] = nc;
- r1[nc] = rmap[i];
- g1[nc] = gmap[i];
- b1[nc] = bmap[i];
- nc++;
- }
- else pc2nc[i] = pc2nc[j];
- }
- /* figure out 'BitsPerPixel' */
- for (i=1; i<8; i++)
- if ( (1<<i) >= nc) break;
-
- BitsPerPixel = i;
- ColorMapSize = 1 << BitsPerPixel;
-
- RWidth = Width = f->width;
- RHeight = Height = f->height;
- LeftOfs = TopOfs = 0;
- if (BitsPerPixel <= 1) InitCodeSize = 2;
- else InitCodeSize = BitsPerPixel;
- curx = 0;
- cury = f->height - 1;
- strcpy((char *) op,"GIF89a"); /* Put in GIF magic number */
- op+=6;
- putgifword(RWidth); /* screen descriptor */
- putgifword(RHeight);
- i = 0x80; /* Yes, there is a color map */
- i |= (8-1)<<4; /* OR in the color resolution (hardwired 8) */
- i |= (BitsPerPixel - 1); /* OR in the # of bits per pixel */
- *(op++) = i;
- *(op++) = Background; /* background color */
- *(op++) = 0;
- for (i=0; i<ColorMapSize; i++) { /* write out Global colormap */
- *(op++) = r1[i];
- *(op++) = g1[i];
- *(op++) = b1[i];
- }
- *(op++) = ','; /* image separator */
- /* Write the Image header */
- putgifword(LeftOfs);
- putgifword(TopOfs);
- putgifword(Width);
- putgifword(Height);
- *(op++) = 0;
- *(op++) = InitCodeSize;
- compress(InitCodeSize+1, f->pixels, f->width*f->height);
- *(op++) = 0;
- *(op++) = ';';
-
- count = (op - (unsigned char *) OutBuffer);
- if (gif_error) return -1;
- else return count;
- }
- /******************************/
- static void putgifword(w)
- int w;
- {
- /* writes a 16-bit integer in GIF order (LSB first) */
- *(op++) = w & 0xff;
- *(op++) = (w>>8)&0xff;
- }
- /***********************************************************************/
- static unsigned long cur_accum = 0;
- static int cur_bits = 0;
- #define GP_BITS 12 /* BITS was already defined on some systems */
- #define HSIZE 5003 /* 80% occupancy */
- typedef unsigned char char_type;
- static int n_bits; /* number of bits/code */
- static int maxbits = GP_BITS; /* user settable max # bits/code */
- static int maxcode; /* maximum code, given n_bits */
- static int maxmaxcode = 1 << GP_BITS; /* NEVER generate this */
- #define MAXCODE(n_bits) ( (1 << (n_bits)) - 1)
- static count_int *htab;
- static unsigned short *codetab;
- static GIFOutBufSize;
- /* static count_int htab [HSIZE];
- static unsigned short codetab [HSIZE]; */
- #define HashTabOf(i) htab[i]
- #define CodeTabOf(i) codetab[i]
- static int hsize = HSIZE; /* for dynamic table sizing */
- /*
- * To save much memory, we overlay the table used by compress() with those
- * used by decompress(). The tab_prefix table is the same size and type
- * as the codetab. The tab_suffix table needs 2**BITS characters. We
- * get this from the beginning of htab. The output stack uses the rest
- * of htab, and contains characters. There is plenty of room for any
- * possible stack (stack used to be 8000 characters).
- */
- #define tab_prefixof(i) CodeTabOf(i)
- #define tab_suffixof(i) ((char_type *)(htab))[i]
- #define de_stack ((char_type *)&tab_suffixof(1<<GP_BITS))
- static int free_ent = 0; /* first unused entry */
- /*
- * block compression parameters -- after all codes are used up,
- * and compression rate changes, start over.
- */
- static int clear_flg = 0;
- static long int out_count = 0; /* # of codes output (for debugging) */
- /*
- * compress stdin to stdout
- *
- * Algorithm: use open addressing double hashing (no chaining) on the
- * prefix code / next character combination. We do a variant of Knuth's
- * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
- * secondary probe. Here, the modular division first probe is gives way
- * to a faster exclusive-or manipulation. Also do block compression with
- * an adaptive reset, whereby the code table is cleared when the compression
- * ratio decreases, but after the table fills. The variable-length output
- * codes are re-sized at this point, and a special CLEAR code is generated
- * for the decompressor. Late addition: construct the table according to
- * file size for noticeable speed improvement on small files. Please direct
- * questions about this implementation to ames!jaw.
- */
- static int g_init_bits;
- static int ClearCode;
- static int EOFCode;
- /********************************************************/
- static void compress(init_bits, data, len)
- int init_bits;
- unsigned char **data;
- int len;
- {
- register long fcode;
- register int i = 0;
- register int c;
- register int ent;
- register int disp;
- register int hsize_reg;
- register int hshift;
- int code_count = 0;
- /* Use the output buffer as temporary storage for GIF data */
- if (OutBufSize < HSIZE*(sizeof(count_int) + sizeof(unsigned short))) {
- gif_error =1;
- return;
- }
- /* Put htab and codetab arrays into the output buffer */
- GIFOutBufSize = OutBufSize - HSIZE*(sizeof(count_int) + sizeof(unsigned short)) - 16;
- GIFOutBufSize = GIFOutBufSize & (~0x3); /* Make sure it's double word alligned */
- htab = (count_int *) ((char *) OutBuffer + GIFOutBufSize);
- codetab = (unsigned short *) ((char *) OutBuffer + GIFOutBufSize + HSIZE*sizeof(count_int));
- /*
- * Set up the globals: g_init_bits - initial number of bits
- * g_outfile - pointer to output file
- */
- g_init_bits = init_bits;
- /* initialize 'compress' globals */
- maxbits = GP_BITS;
- maxmaxcode = 1<<GP_BITS;
- memset(htab,0,sizeof(htab));
- memset(codetab,0,sizeof(codetab));
- hsize = HSIZE;
- free_ent = 0;
- clear_flg = 0;
- out_count = 0;
- cur_accum = 0;
- cur_bits = 0;
- /*
- * Set up the necessary values
- */
- out_count = 0;
- clear_flg = 0;
- maxcode = MAXCODE(n_bits = g_init_bits);
- ClearCode = (1 << (init_bits - 1));
- EOFCode = ClearCode + 1;
- free_ent = ClearCode + 2;
- char_init();
- ent = pc2nc[data[cury][curx]];
- curx++;
- if (curx >= GIF_frame->width) {
- curx = 0;
- cury--;
- }
- len--;
- hshift = 0;
- for ( fcode = (long) hsize; fcode < 65536L; fcode *= 2L )
- hshift++;
- hshift = 8 - hshift; /* set hash code range bound */
- hsize_reg = hsize;
- cl_hash( (count_int) hsize_reg); /* clear hash table */
- output_GIF(ClearCode);
- while (len) {
- c = pc2nc[data[cury][curx]];
- curx++;
- if (curx >= GIF_frame->width) {
- curx = 0;
- cury--;
- }
- len--;
- fcode = (long) ( ( (long) c << maxbits) + ent);
- i = (((int) c << hshift) ^ ent); /* xor hashing */
- if ( HashTabOf (i) == fcode ) {
- ent = CodeTabOf (i);
- continue;
- }
- if ( (long)HashTabOf (i) < 0 ) /* empty slot */
- goto nomatch;
- disp = hsize_reg - i; /* secondary hash (after G. Knott) */
- if ( i == 0 )
- disp = 1;
- probe:
- if ( (i -= disp) < 0 )
- i += hsize_reg;
- if ( HashTabOf (i) == fcode ) {
- ent = CodeTabOf (i);
- continue;
- }
- if ( (long)HashTabOf (i) >= 0 )
- goto probe;
- nomatch:
- output_GIF(ent);
- out_count++;
- ent = c;
- if ( free_ent < maxmaxcode ) {
- CodeTabOf (i) = free_ent++; /* code -> hashtable */
- HashTabOf (i) = fcode;
- }
- else
- cl_block();
- }
- /* Put out the final code */
- output_GIF(ent);
- output_GIF(EOFCode);
- }
- /*****************************************************************
- * TAG( output_GIF )
- *
- * Output the given code.
- * Inputs:
- * code: A n_bits-bit integer. If == -1, then EOF. This assumes
- * that n_bits =< (long)wordsize - 1.
- * Outputs:
- * Outputs code to the file.
- * Assumptions:
- * Chars are 8 bits long.
- * Algorithm:
- * Maintain a BITS character long buffer (so that 8 codes will
- * fit in it exactly). Use the VAX insv instruction to insert each
- * code in turn. When the buffer fills up empty it and start over.
- */
- static
- unsigned long masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
- 0x001F, 0x003F, 0x007F, 0x00FF,
- 0x01FF, 0x03FF, 0x07FF, 0x0FFF,
- 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
- static void output_GIF(code)
- int code;
- {
- cur_accum &= masks[cur_bits];
- if (cur_bits > 0)
- cur_accum |= ((long)code << cur_bits);
- else
- cur_accum = code;
-
- cur_bits += n_bits;
- while( cur_bits >= 8 ) {
- char_out( (int) (cur_accum & 0xff) );
- cur_accum >>= 8;
- cur_bits -= 8;
- }
- /*
- * If the next entry is going to be too big for the code size,
- * then increase it, if possible.
- */
- if (free_ent > maxcode || clear_flg) {
- if( clear_flg ) {
- maxcode = MAXCODE (n_bits = g_init_bits);
- clear_flg = 0;
- }
- else {
- n_bits++;
- if ( n_bits == maxbits )
- maxcode = maxmaxcode;
- else
- maxcode = MAXCODE(n_bits);
- }
- }
-
- if( code == EOFCode ) {
- /* At EOF, write the rest of the buffer */
- while( cur_bits > 0 ) {
- char_out( (int)(cur_accum & 0xff) );
- cur_accum >>= 8;
- cur_bits -= 8;
- }
- flush_char();
- }
- }
- /********************************/
- static void cl_block () /* table clear for block compress */
- {
- /* Clear out the hash table */
- cl_hash ( (count_int) hsize );
- free_ent = ClearCode + 2;
- clear_flg = 1;
- output_GIF(ClearCode);
- }
- /********************************/
- static void cl_hash(hsize) /* reset code table */
- register count_int hsize;
- {
- register count_int *htab_p = htab+hsize;
- register long i;
- register long m1 = -1;
- i = hsize - 16;
- do { /* might use Sys V memset(3) here */
- *(htab_p-16) = m1;
- *(htab_p-15) = m1;
- *(htab_p-14) = m1;
- *(htab_p-13) = m1;
- *(htab_p-12) = m1;
- *(htab_p-11) = m1;
- *(htab_p-10) = m1;
- *(htab_p-9) = m1;
- *(htab_p-8) = m1;
- *(htab_p-7) = m1;
- *(htab_p-6) = m1;
- *(htab_p-5) = m1;
- *(htab_p-4) = m1;
- *(htab_p-3) = m1;
- *(htab_p-2) = m1;
- *(htab_p-1) = m1;
- htab_p -= 16;
- } while ((i -= 16) >= 0);
- for ( i += 16; i > 0; i-- )
- *--htab_p = m1;
- }
- /******************************************************************************
- *
- * GIF Specific routines
- *
- ******************************************************************************/
- /*
- * Number of characters so far in this 'packet'
- */
- static int a_count;
- /*
- * Set up the 'byte output' routine
- */
- static void char_init()
- {
- a_count = 0;
- }
- /*
- * Define the storage for the packet accumulator
- */
- static char accum[ 256 ];
- /*
- * Add a character to the end of the current packet, and if it is 254
- * characters, flush the packet to disk.
- */
- static void char_out(c)
- int c;
- {
- accum[ a_count++ ] = c;
- if( a_count >= 254 )
- flush_char();
- }
- /*
- * Flush the packet to disk, and reset the accumulator
- */
- static void flush_char()
- {
- if (gif_error) return;
- if( a_count > 0 ) {
- *(op++) = a_count;
- memcpy(op,accum,a_count);
- op+=a_count;
- a_count = 0;
-
- if (op > (unsigned char *) ((char *) OutBuffer + (GIFOutBufSize - 2048))) {
- gif_error = 1;
- }
- }
- }
- /* ----------------------------------------------------------------------
- int FrameBuffer_writeGIF(char *filename)
-
- Write a GIF file to filename
- ----------------------------------------------------------------------- */
- int FrameBuffer_writeGIF(FrameBuffer *f, ColorMap *c, char *filename) {
- FILE *file;
- void *buffer;
- int nbytes;
- int bufsize;
- file = fopen(filename,"wb");
- if (file == NULL) return -1;
- bufsize = (f->width*f->height*3)/2;
- buffer = (void *) malloc(bufsize);
- nbytes = FrameBuffer_makeGIF(f,c,buffer,bufsize);
- if (nbytes == -1) {
- free(buffer);
- fclose(file);
- return -1;
- }
- fwrite(buffer,nbytes,1,file);
- fclose(file);
- free(buffer);
- return 0;
- }
-
-
-
-