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|
--- ext/gd/libgd/gd_biggif_out.c.orig Sat Jun 28 15:47:56 2003
+++ ext/gd/libgd/gd_biggif_out.c Sat Jun 28 15:47:56 2003
@@ -0,0 +1,1084 @@
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <stdlib.h>
+#include "gd.h"
+#include "gdhelpers.h"
+
+/*
+** Wrapper functions for this module.
+*/
+
+void gdImageBigGif(gdImagePtr im, FILE *outFile)
+{
+ gdIOCtx *out = gdNewFileCtx(outFile);
+ gdImageBigGifCtx(im, out);
+ out->gd_free(out);
+}
+
+void* gdImageBigGifPtr(gdImagePtr im, int *size)
+{
+ void *rv;
+ gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ gdImageBigGifCtx(im, out);
+ rv = gdDPExtractData(out,size);
+ out->gd_free(out);
+ return rv;
+}
+
+void gdImageGifAnimBegin(gdImagePtr im, FILE *outFile, int GlobalCM, int Loops)
+{
+ gdIOCtx *out = gdNewFileCtx(outFile);
+ gdImageGifAnimBeginCtx(im, out, GlobalCM, Loops);
+ out->gd_free(out);
+}
+
+void *gdImageGifAnimBeginPtr(gdImagePtr im, int *size, int GlobalCM, int Loops)
+{
+ void *rv;
+ gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ gdImageGifAnimBeginCtx(im, out, GlobalCM, Loops);
+ rv = gdDPExtractData(out,size);
+ out->gd_free(out);
+ return rv;
+}
+
+void gdImageBigGifAnimAdd(gdImagePtr im, FILE *outFile, int LocalCM, int LeftOfs, int TopOfs, int Delay, int Disposal)
+{
+ gdIOCtx *out = gdNewFileCtx(outFile);
+ gdImageBigGifAnimAddCtx(im, out, LocalCM, LeftOfs, TopOfs, Delay, Disposal);
+ out->gd_free(out);
+}
+
+void *gdImageBigGifAnimAddPtr(gdImagePtr im, int *size, int LocalCM, int LeftOfs, int TopOfs, int Delay, int Disposal)
+{
+ void *rv;
+ gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ gdImageBigGifAnimAddCtx(im, out, LocalCM, LeftOfs, TopOfs, Delay, Disposal);
+ rv = gdDPExtractData(out,size);
+ out->gd_free(out);
+ return rv;
+}
+
+void gdImageGifAnimEnd(FILE *outFile)
+{
+#if 1
+ putc (';', outFile);
+#else
+ gdIOCtx *out = gdNewFileCtx(outFile);
+ gdImageGifAnimEndCtx(out);
+ out->gd_free(out);
+#endif
+}
+
+void* gdImageGifAnimEndPtr(int *size)
+{
+ char *rv = (char *) gdMalloc (1);
+ *rv = ';';
+ *size = 1;
+ return (void *)rv;
+}
+
+
+/* Code drawn from ppmtogif.c, from the pbmplus package
+**
+** Based on GIFENCOD by David Rowley <mgardi@watdscu.waterloo.edu>. A
+** Lempel-Zim compression based on "compress".
+**
+** Modified by Marcel Wijkstra <wijkstra@fwi.uva.nl>
+**
+** Copyright (C) 1989 by Jef Poskanzer.
+**
+** 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.
+**
+** The Graphics Interchange Format(c) is the Copyright property of
+** CompuServe Incorporated. GIF(sm) is a Service Mark property of
+** CompuServe Incorporated.
+*
+* Heavily modified by Mouse, 1998-02-12.
+* Remove LZW compression.
+* Added miGIF run length compression.
+*
+*/
+
+/*
+ * a code_int must be able to hold 2**GIFBITS values of type int, and also -1
+ */
+typedef int code_int;
+
+static int colorstobpp(int colors);
+static void BumpPixel (void);
+static int GIFNextPixel (gdImagePtr im);
+static void GIFEncode (gdIOCtx *fp, int GWidth, int GHeight, int GInterlace, int Background, int Transparent, int BitsPerPixel, int *Red, int *Green, int *Blue, gdImagePtr im);
+static void GIFAnimEncode(gdIOCtx *fp, int IWidth, int IHeight, int LeftOfs, int TopOfs, int GInterlace, int Transparent, int Delay, int Disposal, int BitsPerPixel, int *Red, int *Green, int *Blue, gdImagePtr im);
+/*static void Putword (int w, gdIOCtx *fp); */
+static void GIFcompress (int, gdIOCtx *, gdImagePtr);
+static void output (code_int code);
+
+/* UNUSED
+* static void char_init (void);
+* static void char_out (int c);
+*/
+
+/* Allows for reuse */
+static void init_statics(void);
+
+void gdImageBigGifCtx(gdImagePtr im, gdIOCtx *out)
+{
+ int interlace, transparent, BitsPerPixel;
+
+ interlace = im->interlace;
+ transparent = im->transparent;
+
+ BitsPerPixel = colorstobpp(im->colorsTotal);
+ /* Clear any old values in statics strewn through the GIF code */
+ init_statics();
+ /* All set, let's do it. */
+ GIFEncode(
+ out, im->sx, im->sy, interlace, 0, transparent, BitsPerPixel,
+ im->red, im->green, im->blue, im);
+}
+
+void gdImageGifAnimBeginCtx(gdImagePtr im, gdIOCtx *out, int GlobalCM, int Loops)
+{
+ int B;
+ int RWidth, RHeight;
+ int Resolution;
+ int ColorMapSize;
+ int BitsPerPixel;
+ int Background = 0;
+ int i;
+
+ BitsPerPixel = colorstobpp(im->colorsTotal);
+ ColorMapSize = 1 << BitsPerPixel;
+
+ RWidth = im->sx;
+ RHeight = im->sy;
+
+ Resolution = BitsPerPixel;
+
+ /*
+ * Write the Magic header
+ */
+ gdPutBuf( "GIF89a", 6, out );
+
+ /*
+ * Write out the screen width and height
+ */
+ Putword( RWidth, out );
+ Putword( RHeight, out );
+
+ /*
+ * Indicate that there is a global colour map
+ */
+ B = GlobalCM > 0 ? 0x80 : 0;
+
+ /*
+ * OR in the resolution
+ */
+ B |= (Resolution - 1) << 5;
+
+ /*
+ * OR in the Bits per Pixel
+ */
+ B |= (BitsPerPixel - 1);
+
+ /*
+ * Write it out
+ */
+ gdPutC( B, out );
+
+ /*
+ * Write out the Background colour
+ */
+ gdPutC( Background, out );
+
+ /*
+ * Byte of 0's (future expansion)
+ */
+ gdPutC( 0, out );
+
+ /*
+ * Write out the Global Colour Map
+ */
+ if (GlobalCM > 0)
+ for( i=0; i<ColorMapSize; ++i ) {
+ gdPutC( im->red[i], out );
+ gdPutC( im->green[i], out );
+ gdPutC( im->blue[i], out );
+ }
+ if (Loops >= 0) {
+ gdPutBuf( "!\377\13NETSCAPE2.0\3\1", 16, out );
+ gdPutC( (unsigned char)(Loops & 255), out );
+ gdPutC( (unsigned char)((Loops >> 8) & 255), out );
+ gdPutC( 0, out );
+ }
+}
+
+void gdImageBigGifAnimAddCtx(gdImagePtr im, gdIOCtx *out, int LocalCM, int LeftOfs, int TopOfs, int Delay, int Disposal)
+{
+ int interlace, transparent, BitsPerPixel;
+
+ interlace = im->interlace;
+ transparent = im->transparent;
+
+ BitsPerPixel = colorstobpp(im->colorsTotal);
+ /* Clear any old values in statics strewn through the GIF code */
+ init_statics();
+ /* All set, let's do it. */
+ GIFAnimEncode(
+ out, im->sx, im->sy, LeftOfs, TopOfs, interlace, transparent,
+ Delay, Disposal, BitsPerPixel,
+ LocalCM > 0 ? im->red : 0, im->green, im->blue, im);
+}
+
+void gdImageGifAnimEndCtx(gdIOCtx *out)
+{
+ /*
+ * Write the GIF file terminator
+ */
+ gdPutC( ';', out );
+}
+
+
+static int
+colorstobpp(int colors)
+{
+ int bpp = 0;
+
+ if ( colors <= 2 )
+ bpp = 1;
+ else if ( colors <= 4 )
+ bpp = 2;
+ else if ( colors <= 8 )
+ bpp = 3;
+ else if ( colors <= 16 )
+ bpp = 4;
+ else if ( colors <= 32 )
+ bpp = 5;
+ else if ( colors <= 64 )
+ bpp = 6;
+ else if ( colors <= 128 )
+ bpp = 7;
+ else if ( colors <= 256 )
+ bpp = 8;
+ return bpp;
+ }
+
+/*****************************************************************************
+ *
+ * GIFENCODE.C - GIF Image compression interface
+ *
+ * GIFEncode( FName, GHeight, GWidth, GInterlace, Background, Transparent,
+ * BitsPerPixel, Red, Green, Blue, gdImagePtr )
+ *
+ *****************************************************************************/
+
+#define TRUE 1
+#define FALSE 0
+
+static int Width, Height;
+static int curx, cury;
+static long CountDown;
+static int Pass = 0;
+static int Interlace;
+
+/*
+ * Bump the 'curx' and 'cury' to point to the next pixel
+ */
+static void
+BumpPixel(void)
+{
+ /*
+ * Bump the current X position
+ */
+ ++curx;
+
+ /*
+ * If we are at the end of a scan line, set curx back to the beginning
+ * If we are interlaced, bump the cury to the appropriate spot,
+ * otherwise, just increment it.
+ */
+ if( curx == Width ) {
+ curx = 0;
+
+ if( !Interlace )
+ ++cury;
+ else {
+ switch( Pass ) {
+
+ case 0:
+ cury += 8;
+ if( cury >= Height ) {
+ ++Pass;
+ cury = 4;
+ }
+ break;
+
+ case 1:
+ cury += 8;
+ if( cury >= Height ) {
+ ++Pass;
+ cury = 2;
+ }
+ break;
+
+ case 2:
+ cury += 4;
+ if( cury >= Height ) {
+ ++Pass;
+ cury = 1;
+ }
+ break;
+
+ case 3:
+ cury += 2;
+ break;
+ }
+ }
+ }
+}
+
+/*
+ * Return the next pixel from the image
+ */
+static int
+GIFNextPixel(gdImagePtr im)
+{
+ int r;
+
+ if( CountDown == 0 )
+ return EOF;
+
+ --CountDown;
+
+ r = gdImageGetPixel(im, curx, cury);
+
+ BumpPixel();
+
+ return r;
+}
+
+/* public */
+
+static void
+GIFEncode(gdIOCtx *fp, int GWidth, int GHeight, int GInterlace, int Background, int Transparent, int BitsPerPixel, int *Red, int *Green, int *Blue, gdImagePtr im)
+{
+ int B;
+ int RWidth, RHeight;
+ int LeftOfs, TopOfs;
+ int Resolution;
+ int ColorMapSize;
+ int InitCodeSize;
+ int i;
+
+ Interlace = GInterlace;
+
+ ColorMapSize = 1 << BitsPerPixel;
+
+ RWidth = Width = GWidth;
+ RHeight = Height = GHeight;
+ LeftOfs = TopOfs = 0;
+
+ Resolution = BitsPerPixel;
+
+ /*
+ * Calculate number of bits we are expecting
+ */
+ CountDown = (long)Width * (long)Height;
+
+ /*
+ * Indicate which pass we are on (if interlace)
+ */
+ Pass = 0;
+
+ /*
+ * The initial code size
+ */
+ if( BitsPerPixel <= 1 )
+ InitCodeSize = 2;
+ else
+ InitCodeSize = BitsPerPixel;
+
+ /*
+ * Set up the current x and y position
+ */
+ curx = cury = 0;
+
+ /*
+ * Write the Magic header
+ */
+ gdPutBuf( Transparent < 0 ? "GIF87a" : "GIF89a", 6, fp );
+
+ /*
+ * Write out the screen width and height
+ */
+ Putword( RWidth, fp );
+ Putword( RHeight, fp );
+
+ /*
+ * Indicate that there is a global colour map
+ */
+ B = 0x80; /* Yes, there is a color map */
+
+ /*
+ * OR in the resolution
+ */
+ B |= (Resolution - 1) << 5;
+
+ /*
+ * OR in the Bits per Pixel
+ */
+ B |= (BitsPerPixel - 1);
+
+ /*
+ * Write it out
+ */
+ gdPutC( B, fp );
+
+ /*
+ * Write out the Background colour
+ */
+ gdPutC( Background, fp );
+
+ /*
+ * Byte of 0's (future expansion)
+ */
+ gdPutC( 0, fp );
+
+ /*
+ * Write out the Global Colour Map
+ */
+ for( i=0; i<ColorMapSize; ++i ) {
+ gdPutC( Red[i], fp );
+ gdPutC( Green[i], fp );
+ gdPutC( Blue[i], fp );
+ }
+
+ /*
+ * Write out extension for transparent colour index, if necessary.
+ */
+ if ( Transparent >= 0 ) {
+ gdPutC( '!', fp );
+ gdPutC( 0xf9, fp );
+ gdPutC( 4, fp );
+ gdPutC( 1, fp );
+ gdPutC( 0, fp );
+ gdPutC( 0, fp );
+ gdPutC( (unsigned char) Transparent, fp );
+ gdPutC( 0, fp );
+ }
+
+ /*
+ * Write an Image separator
+ */
+ gdPutC( ',', fp );
+
+ /*
+ * Write the Image header
+ */
+
+ Putword( LeftOfs, fp );
+ Putword( TopOfs, fp );
+ Putword( Width, fp );
+ Putword( Height, fp );
+
+ /*
+ * Write out whether or not the image is interlaced
+ */
+ if( Interlace )
+ gdPutC( 0x40, fp );
+ else
+ gdPutC( 0x00, fp );
+
+ /*
+ * Write out the initial code size
+ */
+ gdPutC( InitCodeSize, fp );
+
+ /*
+ * Go and actually compress the data
+ */
+ GIFcompress( InitCodeSize+1, fp, im );
+
+ /*
+ * Write out a Zero-length packet (to end the series)
+ */
+ gdPutC( 0, fp );
+
+ /*
+ * Write the GIF file terminator
+ */
+ gdPutC( ';', fp );
+}
+
+static void
+GIFAnimEncode(gdIOCtx *fp, int IWidth, int IHeight, int LeftOfs, int TopOfs, int GInterlace, int Transparent, int Delay, int Disposal, int BitsPerPixel, int *Red, int *Green, int *Blue, gdImagePtr im)
+{
+ int ColorMapSize;
+ int InitCodeSize;
+ int i;
+
+ if (LeftOfs < 0) LeftOfs = 0;
+ if (TopOfs < 0) TopOfs = 0;
+ if (Delay < 0) Delay = 100;
+ if (Disposal < 0) Disposal = 2;
+
+ Interlace = GInterlace;
+
+ ColorMapSize = 1 << BitsPerPixel;
+
+ Width = IWidth;
+ Height = IHeight;
+
+ /*
+ * Calculate number of bits we are expecting
+ */
+ CountDown = (long)Width * (long)Height;
+
+ /*
+ * Indicate which pass we are on (if interlace)
+ */
+ Pass = 0;
+
+ /*
+ * The initial code size
+ */
+ if( BitsPerPixel <= 1 )
+ InitCodeSize = 2;
+ else
+ InitCodeSize = BitsPerPixel;
+
+ /*
+ * Set up the current x and y position
+ */
+ curx = cury = 0;
+
+ /*
+ * Write out extension for image animation and looping
+ */
+ gdPutC( '!', fp );
+ gdPutC( 0xf9, fp );
+ gdPutC( 4, fp );
+ gdPutC( (Transparent >= 0 ? 1 : 0)
+ | (Disposal << 2), fp );
+ gdPutC( (unsigned char)(Delay & 255), fp );
+ gdPutC( (unsigned char)((Delay >> 8) & 255), fp );
+ gdPutC( (unsigned char) Transparent, fp );
+ gdPutC( 0, fp );
+
+ /*
+ * Write an Image separator
+ */
+ gdPutC( ',', fp );
+
+ /*
+ * Write the Image header
+ */
+
+ Putword( LeftOfs, fp );
+ Putword( TopOfs, fp );
+ Putword( Width, fp );
+ Putword( Height, fp );
+
+ /*
+ * Write out whether or not the image is interlaced
+ * and if it includes local colour map.
+ */
+ gdPutC( (Interlace ? 0x40 : 0)
+ | (Red ? 0x80 : 0)
+ | (Red ? BitsPerPixel - 1 : 0), fp );
+
+ /*
+ * Write out the Local Colour Map
+ */
+ if (Red)
+ for( i=0; i<ColorMapSize; ++i ) {
+ gdPutC( Red[i], fp );
+ gdPutC( Green[i], fp );
+ gdPutC( Blue[i], fp );
+ }
+
+ /*
+ * Write out the initial code size
+ */
+ gdPutC( InitCodeSize, fp );
+
+ /*
+ * Go and actually compress the data
+ */
+ GIFcompress( InitCodeSize+1, fp, im );
+
+ /*
+ * Write out a Zero-length packet (to end the series)
+ */
+ gdPutC( 0, fp );
+}
+
+/* Write out a word to the GIF file */
+/*static void */
+/*Putword(int w, gdIOCtx *fp) */
+/*{ */
+/* fputc( w & 0xff, fp ); */
+/* fputc( (w / 256) & 0xff, fp ); */
+/*} */
+
+#define GIFBITS 12
+
+/*-----------------------------------------------------------------------
+ *
+ * miGIF Compression - mouse and ivo's GIF-compatible compression
+ *
+ * -run length encoding compression routines-
+ *
+ * Copyright (C) 1998 Hutchison Avenue Software Corporation
+ * http://www.hasc.com
+ * info@hasc.com
+ *
+ * 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." The Hutchison Avenue
+ * Software Corporation disclaims all warranties, either express or implied,
+ * including but not limited to implied warranties of merchantability and
+ * fitness for a particular purpose, with respect to this code and accompanying
+ * documentation.
+ *
+ * The miGIF compression routines do not, strictly speaking, generate files
+ * conforming to the GIF spec, since the image data is not LZW-compressed
+ * (this is the point: in order to avoid transgression of the Unisys patent
+ * on the LZW algorithm.) However, miGIF generates data streams that any
+ * reasonably sane LZW decompresser will decompress to what we want.
+ *
+ * miGIF compression uses run length encoding. It compresses horizontal runs
+ * of pixels of the same color. This type of compression gives good results
+ * on images with many runs, for example images with lines, text and solid
+ * shapes on a solid-colored background. It gives little or no compression
+ * on images with few runs, for example digital or scanned photos.
+ *
+ * der Mouse
+ * mouse@rodents.montreal.qc.ca
+ * 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
+ *
+ * ivo@hasc.com
+ *
+ * The Graphics Interchange Format(c) is the Copyright property of
+ * CompuServe Incorporated. GIF(sm) is a Service Mark property of
+ * CompuServe Incorporated.
+ *
+ */
+
+static int rl_pixel;
+static int rl_basecode;
+static int rl_count;
+static int rl_table_pixel;
+static int rl_table_max;
+static int just_cleared;
+static int out_bits;
+static int out_bits_init;
+static int out_count;
+static int out_bump;
+static int out_bump_init;
+static int out_clear;
+static int out_clear_init;
+static int max_ocodes;
+static int code_clear;
+static int code_eof;
+static unsigned int obuf;
+static int obits;
+static gdIOCtx *ofile;
+static unsigned char oblock[256];
+static int oblen;
+
+/* Used only when debugging GIF compression code */
+/* #define DEBUGGING_ENVARS */
+
+#ifdef DEBUGGING_ENVARS
+
+static int verbose_set = 0;
+static int verbose;
+#define VERBOSE (verbose_set?verbose:set_verbose())
+
+static int set_verbose(void)
+{
+ verbose = !!getenv("GIF_VERBOSE");
+ verbose_set = 1;
+ return(verbose);
+}
+
+#else
+
+#define VERBOSE 0
+
+#endif
+
+
+static const char *binformat(unsigned int v, int nbits)
+{
+ static char bufs[8][64];
+ static int bhand = 0;
+ unsigned int bit;
+ int bno;
+ char *bp;
+
+ bhand --;
+ if (bhand < 0) bhand = (sizeof(bufs)/sizeof(bufs[0]))-1;
+ bp = &bufs[bhand][0];
+ for (bno=nbits-1,bit=1U<<bno;bno>=0;bno--,bit>>=1)
+ { *bp++ = (v & bit) ? '1' : '0';
+ if (((bno&3) == 0) && (bno != 0)) *bp++ = '.';
+ }
+ *bp = '\0';
+ return(&bufs[bhand][0]);
+}
+
+static void write_block(void)
+{
+ int i;
+
+ if (VERBOSE)
+ { printf("write_block %d:",oblen);
+ for (i=0;i<oblen;i++) printf(" %02x",oblock[i]);
+ printf("\n");
+ }
+ gdPutC(oblen,ofile);
+ gdPutBuf(&oblock[0],oblen,ofile);
+ oblen = 0;
+}
+
+static void block_out(unsigned char c)
+{
+ if (VERBOSE) printf("block_out %s\n",binformat(c,8));
+ oblock[oblen++] = c;
+ if (oblen >= 255) write_block();
+}
+
+static void block_flush(void)
+{
+ if (VERBOSE) printf("block_flush\n");
+ if (oblen > 0) write_block();
+}
+
+static void output(int val)
+{
+ if (VERBOSE) printf("output %s [%s %d %d]\n",binformat(val,out_bits),binformat(obuf,obits),obits,out_bits);
+ obuf |= val << obits;
+ obits += out_bits;
+ while (obits >= 8)
+ { block_out(obuf&0xff);
+ obuf >>= 8;
+ obits -= 8;
+ }
+ if (VERBOSE) printf("output leaving [%s %d]\n",binformat(obuf,obits),obits);
+}
+
+static void output_flush(void)
+{
+ if (VERBOSE) printf("output_flush\n");
+ if (obits > 0) block_out(obuf);
+ block_flush();
+}
+
+static void did_clear(void)
+{
+ if (VERBOSE) printf("did_clear\n");
+ out_bits = out_bits_init;
+ out_bump = out_bump_init;
+ out_clear = out_clear_init;
+ out_count = 0;
+ rl_table_max = 0;
+ just_cleared = 1;
+}
+
+static void output_plain(int c)
+{
+ if (VERBOSE) printf("output_plain %s\n",binformat(c,out_bits));
+ just_cleared = 0;
+ output(c);
+ out_count ++;
+ if (out_count >= out_bump)
+ { out_bits ++;
+ out_bump += 1 << (out_bits - 1);
+ }
+ if (out_count >= out_clear)
+ { output(code_clear);
+ did_clear();
+ }
+}
+
+static unsigned int isqrt(unsigned int x)
+{
+ unsigned int r;
+ unsigned int v;
+
+ if (x < 2) return(x);
+ for (v=x,r=1;v;v>>=2,r<<=1) ;
+ while (1)
+ { v = ((x / r) + r) / 2;
+ if ((v == r) || (v == r+1)) return(r);
+ r = v;
+ }
+}
+
+static unsigned int compute_triangle_count(unsigned int count, unsigned int nrepcodes)
+{
+ unsigned int perrep;
+ unsigned int cost;
+
+ cost = 0;
+ perrep = (nrepcodes * (nrepcodes+1)) / 2;
+ while (count >= perrep)
+ { cost += nrepcodes;
+ count -= perrep;
+ }
+ if (count > 0)
+ { unsigned int n;
+ n = isqrt(count);
+ while ((n*(n+1)) >= 2*count) n --;
+ while ((n*(n+1)) < 2*count) n ++;
+ cost += n;
+ }
+ return(cost);
+}
+
+static void max_out_clear(void)
+{
+ out_clear = max_ocodes;
+}
+
+static void reset_out_clear(void)
+{
+ out_clear = out_clear_init;
+ if (out_count >= out_clear)
+ { output(code_clear);
+ did_clear();
+ }
+}
+
+static void rl_flush_fromclear(int count)
+{
+ int n;
+
+ if (VERBOSE) printf("rl_flush_fromclear %d\n",count);
+ max_out_clear();
+ rl_table_pixel = rl_pixel;
+ n = 1;
+ while (count > 0)
+ { if (n == 1)
+ { rl_table_max = 1;
+ output_plain(rl_pixel);
+ count --;
+ }
+ else if (count >= n)
+ { rl_table_max = n;
+ output_plain(rl_basecode+n-2);
+ count -= n;
+ }
+ else if (count == 1)
+ { rl_table_max ++;
+ output_plain(rl_pixel);
+ count = 0;
+ }
+ else
+ { rl_table_max ++;
+ output_plain(rl_basecode+count-2);
+ count = 0;
+ }
+ if (out_count == 0) n = 1; else n ++;
+ }
+ reset_out_clear();
+ if (VERBOSE) printf("rl_flush_fromclear leaving table_max=%d\n",rl_table_max);
+}
+
+static void rl_flush_clearorrep(int count)
+{
+ int withclr;
+
+ if (VERBOSE) printf("rl_flush_clearorrep %d\n",count);
+ withclr = 1 + compute_triangle_count(count,max_ocodes);
+ if (withclr < count)
+ { output(code_clear);
+ did_clear();
+ rl_flush_fromclear(count);
+ }
+ else
+ { for (;count>0;count--) output_plain(rl_pixel);
+ }
+}
+
+static void rl_flush_withtable(int count)
+{
+ int repmax;
+ int repleft;
+ int leftover;
+
+ if (VERBOSE) printf("rl_flush_withtable %d\n",count);
+ repmax = count / rl_table_max;
+ leftover = count % rl_table_max;
+ repleft = (leftover ? 1 : 0);
+ if (out_count+repmax+repleft > max_ocodes)
+ { repmax = max_ocodes - out_count;
+ leftover = count - (repmax * rl_table_max);
+ repleft = 1 + compute_triangle_count(leftover,max_ocodes);
+ }
+ if (VERBOSE) printf("rl_flush_withtable repmax=%d leftover=%d repleft=%d\n",repmax,leftover,repleft);
+ if (1+compute_triangle_count(count,max_ocodes) < repmax+repleft)
+ { output(code_clear);
+ did_clear();
+ rl_flush_fromclear(count);
+ return;
+ }
+ max_out_clear();
+ for (;repmax>0;repmax--) output_plain(rl_basecode+rl_table_max-2);
+ if (leftover)
+ { if (just_cleared)
+ { rl_flush_fromclear(leftover);
+ }
+ else if (leftover == 1)
+ { output_plain(rl_pixel);
+ }
+ else
+ { output_plain(rl_basecode+leftover-2);
+ }
+ }
+ reset_out_clear();
+}
+
+static void rl_flush(void)
+{
+ /* UNUSED int table_reps; */
+ /* UNUSED int table_extra; */
+
+ if (VERBOSE) printf("rl_flush [ %d %d\n",rl_count,rl_pixel);
+ if (rl_count == 1)
+ { output_plain(rl_pixel);
+ rl_count = 0;
+ if (VERBOSE) printf("rl_flush ]\n");
+ return;
+ }
+ if (just_cleared)
+ { rl_flush_fromclear(rl_count);
+ }
+ else if ((rl_table_max < 2) || (rl_table_pixel != rl_pixel))
+ { rl_flush_clearorrep(rl_count);
+ }
+ else
+ { rl_flush_withtable(rl_count);
+ }
+ if (VERBOSE) printf("rl_flush ]\n");
+ rl_count = 0;
+}
+
+static void GIFcompress(int init_bits, gdIOCtx *outfile, gdImagePtr im)
+{
+ int c;
+
+ ofile = outfile;
+ obuf = 0;
+ obits = 0;
+ oblen = 0;
+ code_clear = 1 << (init_bits - 1);
+ code_eof = code_clear + 1;
+ rl_basecode = code_eof + 1;
+ out_bump_init = (1 << (init_bits - 1)) - 1;
+ /* for images with a lot of runs, making out_clear_init larger will
+ give better compression. */
+ out_clear_init = (init_bits <= 3) ? 9 : (out_bump_init-1);
+#ifdef DEBUGGING_ENVARS
+ { const char *ocienv;
+ ocienv = getenv("GIF_OUT_CLEAR_INIT");
+ if (ocienv)
+ { out_clear_init = atoi(ocienv);
+ if (VERBOSE) printf("[overriding out_clear_init to %d]\n",out_clear_init);
+ }
+ }
+#endif
+ out_bits_init = init_bits;
+ max_ocodes = (1 << GIFBITS) - ((1 << (out_bits_init - 1)) + 3);
+ did_clear();
+ output(code_clear);
+ rl_count = 0;
+ while (1)
+ { c = GIFNextPixel(im);
+ if ((rl_count > 0) && (c != rl_pixel)) rl_flush();
+ if (c == EOF) break;
+ if (rl_pixel == c)
+ { rl_count ++;
+ }
+ else
+ { rl_pixel = c;
+ rl_count = 1;
+ }
+ }
+ output(code_eof);
+ output_flush();
+}
+
+/*-----------------------------------------------------------------------
+ *
+ * End of miGIF section - See copyright notice at start of section.
+ *
+ *-----------------------------------------------------------------------
+*/
+
+/******************************************************************************
+ *
+ * GIF Specific routines
+ *
+ ******************************************************************************/
+
+/*
+ * Number of characters so far in this 'packet'
+ */
+static int a_count;
+
+/*
+ * Set up the 'byte output' routine
+ */
+
+/* UNUSED
+* static void
+* char_init(void)
+* {
+* a_count = 0;
+* }
+*/
+
+/*
+ * Define the storage for the packet accumulator
+ */
+
+/* UNUSED static char accum[ 256 ]; */
+
+static void init_statics(void) {
+ /* Some of these are properly initialized later. What I'm doing
+ here is making sure code that depends on C's initialization
+ of statics doesn't break when the code gets called more
+ than once. */
+ Width = 0;
+ Height = 0;
+ curx = 0;
+ cury = 0;
+ CountDown = 0;
+ Pass = 0;
+ Interlace = 0;
+ a_count = 0;
+}
+
+
+/* +-------------------------------------------------------------------+ */
+/* | Copyright 1990, 1991, 1993, David Koblas. (koblas@netcom.com) | */
+/* | 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. | */
+/* +-------------------------------------------------------------------+ */
+
|