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-rw-r--r--tools/gifconv/hdfgifwr.c516
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diff --git a/tools/gifconv/hdfgifwr.c b/tools/gifconv/hdfgifwr.c
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+/*
+ * hdfgifwr.c - handles writing of GIF files.
+ *
+ * Contains:
+ * hdfWriteGIF(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 <stdio.h>
+#include "gif.h"
+#include <stdlib.h>
+#include <string.h>
+
+typedef BYTE byte;
+typedef long int count_int;
+
+/* indicies into conv24MB */
+#define CONV24_8BIT 0
+#define CONV24_24BIT 1
+#define CONV24_SEP1 2
+#define CONV24_LOCK 3
+#define CONV24_SEP2 4
+#define CONV24_FAST 5
+#define CONV24_SLOW 6
+#define CONV24_BEST 7
+#define CONV24_MAX 8
+
+/* values 'picType' can take */
+#define PIC8 CONV24_8BIT
+#define PIC24 CONV24_24BIT
+
+/* MONO returns total intensity of r,g,b components */
+#define MONO(rd,gn,bl) (((rd)*11 + (gn)*16 + (bl)*5) >> 5) /*.33R+ .5G+ .17B*/
+
+static int Width, Height;
+static int curx, cury;
+static long CountDown;
+static int Interlace;
+
+#ifdef __STDC__
+static void putword(int, FILE *);
+static void compress(int, FILE *, byte *, int);
+static void output(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);
+#else
+static void putword(), compress(), output(), cl_block(), cl_hash();
+static void char_init(), char_out(), flush_char();
+#endif
+
+static byte pc2nc[256],r1[256],g1[256],b1[256];
+
+void xvbzero(s, len)
+ char *s;
+ int len;
+{
+ for ( ; len>0; len--) *s++ = 0;
+}
+
+/*************************************************************/
+int hdfWriteGIF(fp, pic, ptype, w, h, rmap, gmap, bmap, pc2ncmap, numcols, colorstyle, BitsPerPixel)
+ FILE *fp;
+ byte *pic;
+ int ptype, w,h;
+ byte *rmap, *gmap, *bmap , *pc2ncmap;
+ int numcols, colorstyle;
+ int BitsPerPixel;
+{
+ int RWidth, RHeight;
+ int LeftOfs, TopOfs;
+ int ColorMapSize, InitCodeSize, Background;
+ int i;
+ byte *pic8;
+ pic8 = pic;
+
+ Interlace = 0;
+ Background = 0;
+
+ for (i=0; i<256; i++) {
+ pc2nc[i] = pc2ncmap[i];
+ r1[i] = rmap[i];
+ g1[i] = gmap[i];
+ b1[i] = bmap[i];
+ }
+
+ ColorMapSize = 1 << BitsPerPixel;
+
+ RWidth = Width = w;
+ RHeight = Height = h;
+ LeftOfs = TopOfs = 0;
+
+ CountDown = w * h; /* # of pixels we'll be doing */
+
+ if (BitsPerPixel <= 1) InitCodeSize = 2;
+ else InitCodeSize = BitsPerPixel;
+
+ curx = cury = 0;
+
+ if (!fp) {
+ fprintf(stderr, "WriteGIF: file not open for writing\n" );
+ return (1);
+ }
+
+ compress(InitCodeSize+1, fp, pic8, w*h);
+
+
+ if (ferror(fp)) return -1;
+ return (0);
+}
+
+
+
+
+/******************************/
+static void putword(w, fp)
+int w;
+FILE *fp;
+{
+ /* writes a 16-bit integer in GIF order (LSB first) */
+
+ fputc(w &0xff, fp);
+
+ fputc((w>>8)&0xff,fp);
+}
+
+
+
+
+/***********************************************************************/
+static unsigned long cur_accum = 0;
+static int cur_bits = 0;
+
+#define MAXCODE(n_bits) ( (1 << (n_bits)) - 1)
+#define min(a,b) ((a>b) ? b : a)
+#define XV_BITS 12 /* BITS was already defined on some systems */
+#define MSDOS 1
+#define HSIZE 5003 /* 80% occupancy */
+
+typedef unsigned char char_type;
+static int n_bits; /* number of bits/code */
+static int maxbits = XV_BITS; /* user settable max # bits/code */
+static int maxcode; /* maximum code, given n_bits */
+static int maxmaxcode = 1 << XV_BITS; /* NEVER generate this */
+
+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<<XV_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 in_count = 1; /* length of input */
+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 FILE *g_outfile;
+
+static int ClearCode;
+static int EOFCode;
+
+/********************************************************/
+static void compress(init_bits, outfile, data, len)
+int init_bits;
+FILE *outfile;
+byte *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;
+
+ /*
+ * Set up the globals: g_init_bits - initial number of bits
+ * g_outfile - pointer to output file
+ */
+ g_init_bits = init_bits;
+ g_outfile = outfile;
+
+ /* initialize 'compress' globals */
+ maxbits = XV_BITS;
+ maxmaxcode = 1<<XV_BITS;
+ xvbzero((char *) htab, sizeof(htab));
+ xvbzero((char *) codetab, sizeof(codetab));
+ hsize = HSIZE;
+ free_ent = 0;
+ clear_flg = 0;
+ in_count = 1;
+ out_count = 0;
+ cur_accum = 0;
+ cur_bits = 0;
+
+
+ /*
+ * Set up the necessary values
+ */
+ out_count = 0;
+ clear_flg = 0;
+ in_count = 1;
+ maxcode = MAXCODE(n_bits = g_init_bits);
+
+ ClearCode = (1 << (init_bits - 1));
+ EOFCode = ClearCode + 1;
+ free_ent = ClearCode + 2;
+
+ char_init();
+ ent = pc2nc[*data++]; 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(ClearCode);
+
+ while (len) {
+ c = pc2nc[*data++]; len--;
+ in_count++;
+
+ fcode = (long) ( ( (long) c << maxbits) + ent);
+ i = (((int) c << hshift) ^ ent); /* xor hashing */
+
+ if ( HashTabOf (i) == fcode ) {
+ ent = CodeTabOf (i);
+ continue;
+ }
+
+ else 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(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(ent);
+ out_count++;
+ output(EOFCode);
+}
+
+
+/*****************************************************************
+ * TAG( output )
+ *
+ * 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(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( (unsigned 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( (unsigned int)(cur_accum & 0xff) );
+ cur_accum >>= 8;
+ cur_bits -= 8;
+ }
+
+ flush_char();
+
+ fflush( g_outfile );
+
+#ifdef FOO
+ if( ferror( g_outfile ) )
+ FatalError("unable to write GIF file");
+#endif
+ }
+}
+
+
+/********************************/
+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(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( a_count > 0 ) {
+ fputc( a_count, g_outfile );
+ fwrite( accum, 1, a_count, g_outfile );
+ a_count = 0;
+ }
+}
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