Shoaib Ahmed / Mbed 2 deprecated uzairkhan

Final 350 project

Dependencies:   uzair Camera_LS_Y201 F7_Ethernet LCD_DISCO_F746NG NetworkAPI SDFileSystem mbed

includes/wrgif.c@0:791a779d6220, 2017-07-31 (annotated)

Committer:
shoaib_ahmed
Date:
Mon Jul 31 09:16:35 2017 +0000
Revision:
0:791a779d6220
final project;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
shoaib_ahmed 0:791a779d6220 1 /*
shoaib_ahmed 0:791a779d6220 2 * wrgif.c
shoaib_ahmed 0:791a779d6220 3 *
shoaib_ahmed 0:791a779d6220 4 * Copyright (C) 1991-1997, Thomas G. Lane.
shoaib_ahmed 0:791a779d6220 5 * Modified 2015 by Guido Vollbeding.
shoaib_ahmed 0:791a779d6220 6 * This file is part of the Independent JPEG Group's software.
shoaib_ahmed 0:791a779d6220 7 * For conditions of distribution and use, see the accompanying README file.
shoaib_ahmed 0:791a779d6220 8 *
shoaib_ahmed 0:791a779d6220 9 * This file contains routines to write output images in GIF format.
shoaib_ahmed 0:791a779d6220 10 *
shoaib_ahmed 0:791a779d6220 11 **************************************************************************
shoaib_ahmed 0:791a779d6220 12 * NOTE: to avoid entanglements with Unisys' patent on LZW compression, *
shoaib_ahmed 0:791a779d6220 13 * this code has been modified to output "uncompressed GIF" files. *
shoaib_ahmed 0:791a779d6220 14 * There is no trace of the LZW algorithm in this file. *
shoaib_ahmed 0:791a779d6220 15 **************************************************************************
shoaib_ahmed 0:791a779d6220 16 *
shoaib_ahmed 0:791a779d6220 17 * These routines may need modification for non-Unix environments or
shoaib_ahmed 0:791a779d6220 18 * specialized applications. As they stand, they assume output to
shoaib_ahmed 0:791a779d6220 19 * an ordinary stdio stream.
shoaib_ahmed 0:791a779d6220 20 */
shoaib_ahmed 0:791a779d6220 21
shoaib_ahmed 0:791a779d6220 22 /*
shoaib_ahmed 0:791a779d6220 23 * This code is loosely based on ppmtogif from the PBMPLUS distribution
shoaib_ahmed 0:791a779d6220 24 * of Feb. 1991. That file contains the following copyright notice:
shoaib_ahmed 0:791a779d6220 25 * Based on GIFENCODE by David Rowley <mgardi@watdscu.waterloo.edu>.
shoaib_ahmed 0:791a779d6220 26 * Lempel-Ziv compression based on "compress" by Spencer W. Thomas et al.
shoaib_ahmed 0:791a779d6220 27 * Copyright (C) 1989 by Jef Poskanzer.
shoaib_ahmed 0:791a779d6220 28 * Permission to use, copy, modify, and distribute this software and its
shoaib_ahmed 0:791a779d6220 29 * documentation for any purpose and without fee is hereby granted, provided
shoaib_ahmed 0:791a779d6220 30 * that the above copyright notice appear in all copies and that both that
shoaib_ahmed 0:791a779d6220 31 * copyright notice and this permission notice appear in supporting
shoaib_ahmed 0:791a779d6220 32 * documentation. This software is provided "as is" without express or
shoaib_ahmed 0:791a779d6220 33 * implied warranty.
shoaib_ahmed 0:791a779d6220 34 *
shoaib_ahmed 0:791a779d6220 35 * We are also required to state that
shoaib_ahmed 0:791a779d6220 36 * "The Graphics Interchange Format(c) is the Copyright property of
shoaib_ahmed 0:791a779d6220 37 * CompuServe Incorporated. GIF(sm) is a Service Mark property of
shoaib_ahmed 0:791a779d6220 38 * CompuServe Incorporated."
shoaib_ahmed 0:791a779d6220 39 */
shoaib_ahmed 0:791a779d6220 40
shoaib_ahmed 0:791a779d6220 41 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
shoaib_ahmed 0:791a779d6220 42
shoaib_ahmed 0:791a779d6220 43 #ifdef GIF_SUPPORTED
shoaib_ahmed 0:791a779d6220 44
shoaib_ahmed 0:791a779d6220 45
shoaib_ahmed 0:791a779d6220 46 /* Private version of data destination object */
shoaib_ahmed 0:791a779d6220 47
shoaib_ahmed 0:791a779d6220 48 typedef struct {
shoaib_ahmed 0:791a779d6220 49 struct djpeg_dest_struct pub; /* public fields */
shoaib_ahmed 0:791a779d6220 50
shoaib_ahmed 0:791a779d6220 51 j_decompress_ptr cinfo; /* back link saves passing separate parm */
shoaib_ahmed 0:791a779d6220 52
shoaib_ahmed 0:791a779d6220 53 /* State for packing variable-width codes into a bitstream */
shoaib_ahmed 0:791a779d6220 54 int n_bits; /* current number of bits/code */
shoaib_ahmed 0:791a779d6220 55 int maxcode; /* maximum code, given n_bits */
shoaib_ahmed 0:791a779d6220 56 INT32 cur_accum; /* holds bits not yet output */
shoaib_ahmed 0:791a779d6220 57 int cur_bits; /* # of bits in cur_accum */
shoaib_ahmed 0:791a779d6220 58
shoaib_ahmed 0:791a779d6220 59 /* State for GIF code assignment */
shoaib_ahmed 0:791a779d6220 60 int ClearCode; /* clear code (doesn't change) */
shoaib_ahmed 0:791a779d6220 61 int EOFCode; /* EOF code (ditto) */
shoaib_ahmed 0:791a779d6220 62 int code_counter; /* counts output symbols */
shoaib_ahmed 0:791a779d6220 63
shoaib_ahmed 0:791a779d6220 64 /* GIF data packet construction buffer */
shoaib_ahmed 0:791a779d6220 65 int bytesinpkt; /* # of bytes in current packet */
shoaib_ahmed 0:791a779d6220 66 char packetbuf[256]; /* workspace for accumulating packet */
shoaib_ahmed 0:791a779d6220 67
shoaib_ahmed 0:791a779d6220 68 } gif_dest_struct;
shoaib_ahmed 0:791a779d6220 69
shoaib_ahmed 0:791a779d6220 70 typedef gif_dest_struct * gif_dest_ptr;
shoaib_ahmed 0:791a779d6220 71
shoaib_ahmed 0:791a779d6220 72 /* Largest value that will fit in N bits */
shoaib_ahmed 0:791a779d6220 73 #define MAXCODE(n_bits) ((1 << (n_bits)) - 1)
shoaib_ahmed 0:791a779d6220 74
shoaib_ahmed 0:791a779d6220 75
shoaib_ahmed 0:791a779d6220 76 /*
shoaib_ahmed 0:791a779d6220 77 * Routines to package finished data bytes into GIF data blocks.
shoaib_ahmed 0:791a779d6220 78 * A data block consists of a count byte (1..255) and that many data bytes.
shoaib_ahmed 0:791a779d6220 79 */
shoaib_ahmed 0:791a779d6220 80
shoaib_ahmed 0:791a779d6220 81 LOCAL(void)
shoaib_ahmed 0:791a779d6220 82 flush_packet (gif_dest_ptr dinfo)
shoaib_ahmed 0:791a779d6220 83 /* flush any accumulated data */
shoaib_ahmed 0:791a779d6220 84 {
shoaib_ahmed 0:791a779d6220 85 if (dinfo->bytesinpkt > 0) { /* never write zero-length packet */
shoaib_ahmed 0:791a779d6220 86 dinfo->packetbuf[0] = (char) dinfo->bytesinpkt++;
shoaib_ahmed 0:791a779d6220 87 if (JFWRITE(dinfo->pub.output_file, dinfo->packetbuf, dinfo->bytesinpkt)
shoaib_ahmed 0:791a779d6220 88 != (size_t) dinfo->bytesinpkt)
shoaib_ahmed 0:791a779d6220 89 ERREXIT(dinfo->cinfo, JERR_FILE_WRITE);
shoaib_ahmed 0:791a779d6220 90 dinfo->bytesinpkt = 0;
shoaib_ahmed 0:791a779d6220 91 }
shoaib_ahmed 0:791a779d6220 92 }
shoaib_ahmed 0:791a779d6220 93
shoaib_ahmed 0:791a779d6220 94
shoaib_ahmed 0:791a779d6220 95 /* Add a character to current packet; flush to disk if necessary */
shoaib_ahmed 0:791a779d6220 96 #define CHAR_OUT(dinfo,c) \
shoaib_ahmed 0:791a779d6220 97 { (dinfo)->packetbuf[++(dinfo)->bytesinpkt] = (char) (c); \
shoaib_ahmed 0:791a779d6220 98 if ((dinfo)->bytesinpkt >= 255) \
shoaib_ahmed 0:791a779d6220 99 flush_packet(dinfo); \
shoaib_ahmed 0:791a779d6220 100 }
shoaib_ahmed 0:791a779d6220 101
shoaib_ahmed 0:791a779d6220 102
shoaib_ahmed 0:791a779d6220 103 /* Routine to convert variable-width codes into a byte stream */
shoaib_ahmed 0:791a779d6220 104
shoaib_ahmed 0:791a779d6220 105 LOCAL(void)
shoaib_ahmed 0:791a779d6220 106 output (gif_dest_ptr dinfo, int code)
shoaib_ahmed 0:791a779d6220 107 /* Emit a code of n_bits bits */
shoaib_ahmed 0:791a779d6220 108 /* Uses cur_accum and cur_bits to reblock into 8-bit bytes */
shoaib_ahmed 0:791a779d6220 109 {
shoaib_ahmed 0:791a779d6220 110 dinfo->cur_accum |= ((INT32) code) << dinfo->cur_bits;
shoaib_ahmed 0:791a779d6220 111 dinfo->cur_bits += dinfo->n_bits;
shoaib_ahmed 0:791a779d6220 112
shoaib_ahmed 0:791a779d6220 113 while (dinfo->cur_bits >= 8) {
shoaib_ahmed 0:791a779d6220 114 CHAR_OUT(dinfo, dinfo->cur_accum & 0xFF);
shoaib_ahmed 0:791a779d6220 115 dinfo->cur_accum >>= 8;
shoaib_ahmed 0:791a779d6220 116 dinfo->cur_bits -= 8;
shoaib_ahmed 0:791a779d6220 117 }
shoaib_ahmed 0:791a779d6220 118 }
shoaib_ahmed 0:791a779d6220 119
shoaib_ahmed 0:791a779d6220 120
shoaib_ahmed 0:791a779d6220 121 /* The pseudo-compression algorithm.
shoaib_ahmed 0:791a779d6220 122 *
shoaib_ahmed 0:791a779d6220 123 * In this module we simply output each pixel value as a separate symbol;
shoaib_ahmed 0:791a779d6220 124 * thus, no compression occurs. In fact, there is expansion of one bit per
shoaib_ahmed 0:791a779d6220 125 * pixel, because we use a symbol width one bit wider than the pixel width.
shoaib_ahmed 0:791a779d6220 126 *
shoaib_ahmed 0:791a779d6220 127 * GIF ordinarily uses variable-width symbols, and the decoder will expect
shoaib_ahmed 0:791a779d6220 128 * to ratchet up the symbol width after a fixed number of symbols.
shoaib_ahmed 0:791a779d6220 129 * To simplify the logic and keep the expansion penalty down, we emit a
shoaib_ahmed 0:791a779d6220 130 * GIF Clear code to reset the decoder just before the width would ratchet up.
shoaib_ahmed 0:791a779d6220 131 * Thus, all the symbols in the output file will have the same bit width.
shoaib_ahmed 0:791a779d6220 132 * Note that emitting the Clear codes at the right times is a mere matter of
shoaib_ahmed 0:791a779d6220 133 * counting output symbols and is in no way dependent on the LZW patent.
shoaib_ahmed 0:791a779d6220 134 *
shoaib_ahmed 0:791a779d6220 135 * With a small basic pixel width (low color count), Clear codes will be
shoaib_ahmed 0:791a779d6220 136 * needed very frequently, causing the file to expand even more. So this
shoaib_ahmed 0:791a779d6220 137 * simplistic approach wouldn't work too well on bilevel images, for example.
shoaib_ahmed 0:791a779d6220 138 * But for output of JPEG conversions the pixel width will usually be 8 bits
shoaib_ahmed 0:791a779d6220 139 * (129 to 256 colors), so the overhead added by Clear symbols is only about
shoaib_ahmed 0:791a779d6220 140 * one symbol in every 256.
shoaib_ahmed 0:791a779d6220 141 */
shoaib_ahmed 0:791a779d6220 142
shoaib_ahmed 0:791a779d6220 143 LOCAL(void)
shoaib_ahmed 0:791a779d6220 144 compress_init (gif_dest_ptr dinfo, int i_bits)
shoaib_ahmed 0:791a779d6220 145 /* Initialize pseudo-compressor */
shoaib_ahmed 0:791a779d6220 146 {
shoaib_ahmed 0:791a779d6220 147 /* init all the state variables */
shoaib_ahmed 0:791a779d6220 148 dinfo->n_bits = i_bits;
shoaib_ahmed 0:791a779d6220 149 dinfo->maxcode = MAXCODE(dinfo->n_bits);
shoaib_ahmed 0:791a779d6220 150 dinfo->ClearCode = (1 << (i_bits - 1));
shoaib_ahmed 0:791a779d6220 151 dinfo->EOFCode = dinfo->ClearCode + 1;
shoaib_ahmed 0:791a779d6220 152 dinfo->code_counter = dinfo->ClearCode + 2;
shoaib_ahmed 0:791a779d6220 153 /* init output buffering vars */
shoaib_ahmed 0:791a779d6220 154 dinfo->bytesinpkt = 0;
shoaib_ahmed 0:791a779d6220 155 dinfo->cur_accum = 0;
shoaib_ahmed 0:791a779d6220 156 dinfo->cur_bits = 0;
shoaib_ahmed 0:791a779d6220 157 /* GIF specifies an initial Clear code */
shoaib_ahmed 0:791a779d6220 158 output(dinfo, dinfo->ClearCode);
shoaib_ahmed 0:791a779d6220 159 }
shoaib_ahmed 0:791a779d6220 160
shoaib_ahmed 0:791a779d6220 161
shoaib_ahmed 0:791a779d6220 162 LOCAL(void)
shoaib_ahmed 0:791a779d6220 163 compress_pixel (gif_dest_ptr dinfo, int c)
shoaib_ahmed 0:791a779d6220 164 /* Accept and "compress" one pixel value.
shoaib_ahmed 0:791a779d6220 165 * The given value must be less than n_bits wide.
shoaib_ahmed 0:791a779d6220 166 */
shoaib_ahmed 0:791a779d6220 167 {
shoaib_ahmed 0:791a779d6220 168 /* Output the given pixel value as a symbol. */
shoaib_ahmed 0:791a779d6220 169 output(dinfo, c);
shoaib_ahmed 0:791a779d6220 170 /* Issue Clear codes often enough to keep the reader from ratcheting up
shoaib_ahmed 0:791a779d6220 171 * its symbol size.
shoaib_ahmed 0:791a779d6220 172 */
shoaib_ahmed 0:791a779d6220 173 if (dinfo->code_counter < dinfo->maxcode) {
shoaib_ahmed 0:791a779d6220 174 dinfo->code_counter++;
shoaib_ahmed 0:791a779d6220 175 } else {
shoaib_ahmed 0:791a779d6220 176 output(dinfo, dinfo->ClearCode);
shoaib_ahmed 0:791a779d6220 177 dinfo->code_counter = dinfo->ClearCode + 2; /* reset the counter */
shoaib_ahmed 0:791a779d6220 178 }
shoaib_ahmed 0:791a779d6220 179 }
shoaib_ahmed 0:791a779d6220 180
shoaib_ahmed 0:791a779d6220 181
shoaib_ahmed 0:791a779d6220 182 LOCAL(void)
shoaib_ahmed 0:791a779d6220 183 compress_term (gif_dest_ptr dinfo)
shoaib_ahmed 0:791a779d6220 184 /* Clean up at end */
shoaib_ahmed 0:791a779d6220 185 {
shoaib_ahmed 0:791a779d6220 186 /* Send an EOF code */
shoaib_ahmed 0:791a779d6220 187 output(dinfo, dinfo->EOFCode);
shoaib_ahmed 0:791a779d6220 188 /* Flush the bit-packing buffer */
shoaib_ahmed 0:791a779d6220 189 if (dinfo->cur_bits > 0) {
shoaib_ahmed 0:791a779d6220 190 CHAR_OUT(dinfo, dinfo->cur_accum & 0xFF);
shoaib_ahmed 0:791a779d6220 191 }
shoaib_ahmed 0:791a779d6220 192 /* Flush the packet buffer */
shoaib_ahmed 0:791a779d6220 193 flush_packet(dinfo);
shoaib_ahmed 0:791a779d6220 194 }
shoaib_ahmed 0:791a779d6220 195
shoaib_ahmed 0:791a779d6220 196
shoaib_ahmed 0:791a779d6220 197 /* GIF header construction */
shoaib_ahmed 0:791a779d6220 198
shoaib_ahmed 0:791a779d6220 199
shoaib_ahmed 0:791a779d6220 200 LOCAL(void)
shoaib_ahmed 0:791a779d6220 201 put_word (gif_dest_ptr dinfo, unsigned int w)
shoaib_ahmed 0:791a779d6220 202 /* Emit a 16-bit word, LSB first */
shoaib_ahmed 0:791a779d6220 203 {
shoaib_ahmed 0:791a779d6220 204 putc(w & 0xFF, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 205 putc((w >> 8) & 0xFF, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 206 }
shoaib_ahmed 0:791a779d6220 207
shoaib_ahmed 0:791a779d6220 208
shoaib_ahmed 0:791a779d6220 209 LOCAL(void)
shoaib_ahmed 0:791a779d6220 210 put_3bytes (gif_dest_ptr dinfo, int val)
shoaib_ahmed 0:791a779d6220 211 /* Emit 3 copies of same byte value --- handy subr for colormap construction */
shoaib_ahmed 0:791a779d6220 212 {
shoaib_ahmed 0:791a779d6220 213 putc(val, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 214 putc(val, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 215 putc(val, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 216 }
shoaib_ahmed 0:791a779d6220 217
shoaib_ahmed 0:791a779d6220 218
shoaib_ahmed 0:791a779d6220 219 LOCAL(void)
shoaib_ahmed 0:791a779d6220 220 emit_header (gif_dest_ptr dinfo, int num_colors, JSAMPARRAY colormap)
shoaib_ahmed 0:791a779d6220 221 /* Output the GIF file header, including color map */
shoaib_ahmed 0:791a779d6220 222 /* If colormap==NULL, synthesize a grayscale colormap */
shoaib_ahmed 0:791a779d6220 223 {
shoaib_ahmed 0:791a779d6220 224 int BitsPerPixel, ColorMapSize, InitCodeSize, FlagByte;
shoaib_ahmed 0:791a779d6220 225 int cshift = dinfo->cinfo->data_precision - 8;
shoaib_ahmed 0:791a779d6220 226 int i;
shoaib_ahmed 0:791a779d6220 227
shoaib_ahmed 0:791a779d6220 228 if (num_colors > 256)
shoaib_ahmed 0:791a779d6220 229 ERREXIT1(dinfo->cinfo, JERR_TOO_MANY_COLORS, num_colors);
shoaib_ahmed 0:791a779d6220 230 /* Compute bits/pixel and related values */
shoaib_ahmed 0:791a779d6220 231 BitsPerPixel = 1;
shoaib_ahmed 0:791a779d6220 232 while (num_colors > (1 << BitsPerPixel))
shoaib_ahmed 0:791a779d6220 233 BitsPerPixel++;
shoaib_ahmed 0:791a779d6220 234 ColorMapSize = 1 << BitsPerPixel;
shoaib_ahmed 0:791a779d6220 235 if (BitsPerPixel <= 1)
shoaib_ahmed 0:791a779d6220 236 InitCodeSize = 2;
shoaib_ahmed 0:791a779d6220 237 else
shoaib_ahmed 0:791a779d6220 238 InitCodeSize = BitsPerPixel;
shoaib_ahmed 0:791a779d6220 239 /*
shoaib_ahmed 0:791a779d6220 240 * Write the GIF header.
shoaib_ahmed 0:791a779d6220 241 * Note that we generate a plain GIF87 header for maximum compatibility.
shoaib_ahmed 0:791a779d6220 242 */
shoaib_ahmed 0:791a779d6220 243 putc('G', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 244 putc('I', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 245 putc('F', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 246 putc('8', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 247 putc('7', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 248 putc('a', dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 249 /* Write the Logical Screen Descriptor */
shoaib_ahmed 0:791a779d6220 250 put_word(dinfo, (unsigned int) dinfo->cinfo->output_width);
shoaib_ahmed 0:791a779d6220 251 put_word(dinfo, (unsigned int) dinfo->cinfo->output_height);
shoaib_ahmed 0:791a779d6220 252 FlagByte = 0x80; /* Yes, there is a global color table */
shoaib_ahmed 0:791a779d6220 253 FlagByte |= (BitsPerPixel-1) << 4; /* color resolution */
shoaib_ahmed 0:791a779d6220 254 FlagByte |= (BitsPerPixel-1); /* size of global color table */
shoaib_ahmed 0:791a779d6220 255 putc(FlagByte, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 256 putc(0, dinfo->pub.output_file); /* Background color index */
shoaib_ahmed 0:791a779d6220 257 putc(0, dinfo->pub.output_file); /* Reserved (aspect ratio in GIF89) */
shoaib_ahmed 0:791a779d6220 258 /* Write the Global Color Map */
shoaib_ahmed 0:791a779d6220 259 /* If the color map is more than 8 bits precision, */
shoaib_ahmed 0:791a779d6220 260 /* we reduce it to 8 bits by shifting */
shoaib_ahmed 0:791a779d6220 261 for (i=0; i < ColorMapSize; i++) {
shoaib_ahmed 0:791a779d6220 262 if (i < num_colors) {
shoaib_ahmed 0:791a779d6220 263 if (colormap != NULL) {
shoaib_ahmed 0:791a779d6220 264 if (dinfo->cinfo->out_color_space == JCS_RGB) {
shoaib_ahmed 0:791a779d6220 265 /* Normal case: RGB color map */
shoaib_ahmed 0:791a779d6220 266 putc(GETJSAMPLE(colormap[0][i]) >> cshift, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 267 putc(GETJSAMPLE(colormap[1][i]) >> cshift, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 268 putc(GETJSAMPLE(colormap[2][i]) >> cshift, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 269 } else {
shoaib_ahmed 0:791a779d6220 270 /* Grayscale "color map": possible if quantizing grayscale image */
shoaib_ahmed 0:791a779d6220 271 put_3bytes(dinfo, GETJSAMPLE(colormap[0][i]) >> cshift);
shoaib_ahmed 0:791a779d6220 272 }
shoaib_ahmed 0:791a779d6220 273 } else {
shoaib_ahmed 0:791a779d6220 274 /* Create a grayscale map of num_colors values, range 0..255 */
shoaib_ahmed 0:791a779d6220 275 put_3bytes(dinfo, (i * 255 + (num_colors-1)/2) / (num_colors-1));
shoaib_ahmed 0:791a779d6220 276 }
shoaib_ahmed 0:791a779d6220 277 } else {
shoaib_ahmed 0:791a779d6220 278 /* fill out the map to a power of 2 */
shoaib_ahmed 0:791a779d6220 279 put_3bytes(dinfo, 0);
shoaib_ahmed 0:791a779d6220 280 }
shoaib_ahmed 0:791a779d6220 281 }
shoaib_ahmed 0:791a779d6220 282 /* Write image separator and Image Descriptor */
shoaib_ahmed 0:791a779d6220 283 putc(',', dinfo->pub.output_file); /* separator */
shoaib_ahmed 0:791a779d6220 284 put_word(dinfo, 0); /* left/top offset */
shoaib_ahmed 0:791a779d6220 285 put_word(dinfo, 0);
shoaib_ahmed 0:791a779d6220 286 put_word(dinfo, (unsigned int) dinfo->cinfo->output_width); /* image size */
shoaib_ahmed 0:791a779d6220 287 put_word(dinfo, (unsigned int) dinfo->cinfo->output_height);
shoaib_ahmed 0:791a779d6220 288 /* flag byte: not interlaced, no local color map */
shoaib_ahmed 0:791a779d6220 289 putc(0x00, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 290 /* Write Initial Code Size byte */
shoaib_ahmed 0:791a779d6220 291 putc(InitCodeSize, dinfo->pub.output_file);
shoaib_ahmed 0:791a779d6220 292
shoaib_ahmed 0:791a779d6220 293 /* Initialize for "compression" of image data */
shoaib_ahmed 0:791a779d6220 294 compress_init(dinfo, InitCodeSize+1);
shoaib_ahmed 0:791a779d6220 295 }
shoaib_ahmed 0:791a779d6220 296
shoaib_ahmed 0:791a779d6220 297
shoaib_ahmed 0:791a779d6220 298 /*
shoaib_ahmed 0:791a779d6220 299 * Startup: write the file header.
shoaib_ahmed 0:791a779d6220 300 */
shoaib_ahmed 0:791a779d6220 301
shoaib_ahmed 0:791a779d6220 302 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 303 start_output_gif (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
shoaib_ahmed 0:791a779d6220 304 {
shoaib_ahmed 0:791a779d6220 305 gif_dest_ptr dest = (gif_dest_ptr) dinfo;
shoaib_ahmed 0:791a779d6220 306
shoaib_ahmed 0:791a779d6220 307 if (cinfo->quantize_colors)
shoaib_ahmed 0:791a779d6220 308 emit_header(dest, cinfo->actual_number_of_colors, cinfo->colormap);
shoaib_ahmed 0:791a779d6220 309 else
shoaib_ahmed 0:791a779d6220 310 emit_header(dest, 256, (JSAMPARRAY) NULL);
shoaib_ahmed 0:791a779d6220 311 }
shoaib_ahmed 0:791a779d6220 312
shoaib_ahmed 0:791a779d6220 313
shoaib_ahmed 0:791a779d6220 314 /*
shoaib_ahmed 0:791a779d6220 315 * Write some pixel data.
shoaib_ahmed 0:791a779d6220 316 * In this module rows_supplied will always be 1.
shoaib_ahmed 0:791a779d6220 317 */
shoaib_ahmed 0:791a779d6220 318
shoaib_ahmed 0:791a779d6220 319 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 320 put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
shoaib_ahmed 0:791a779d6220 321 JDIMENSION rows_supplied)
shoaib_ahmed 0:791a779d6220 322 {
shoaib_ahmed 0:791a779d6220 323 gif_dest_ptr dest = (gif_dest_ptr) dinfo;
shoaib_ahmed 0:791a779d6220 324 register JSAMPROW ptr;
shoaib_ahmed 0:791a779d6220 325 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 326
shoaib_ahmed 0:791a779d6220 327 ptr = dest->pub.buffer[0];
shoaib_ahmed 0:791a779d6220 328 for (col = cinfo->output_width; col > 0; col--) {
shoaib_ahmed 0:791a779d6220 329 compress_pixel(dest, GETJSAMPLE(*ptr++));
shoaib_ahmed 0:791a779d6220 330 }
shoaib_ahmed 0:791a779d6220 331 }
shoaib_ahmed 0:791a779d6220 332
shoaib_ahmed 0:791a779d6220 333
shoaib_ahmed 0:791a779d6220 334 /*
shoaib_ahmed 0:791a779d6220 335 * Finish up at the end of the file.
shoaib_ahmed 0:791a779d6220 336 */
shoaib_ahmed 0:791a779d6220 337
shoaib_ahmed 0:791a779d6220 338 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 339 finish_output_gif (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
shoaib_ahmed 0:791a779d6220 340 {
shoaib_ahmed 0:791a779d6220 341 gif_dest_ptr dest = (gif_dest_ptr) dinfo;
shoaib_ahmed 0:791a779d6220 342
shoaib_ahmed 0:791a779d6220 343 /* Flush "compression" mechanism */
shoaib_ahmed 0:791a779d6220 344 compress_term(dest);
shoaib_ahmed 0:791a779d6220 345 /* Write a zero-length data block to end the series */
shoaib_ahmed 0:791a779d6220 346 putc(0, dest->pub.output_file);
shoaib_ahmed 0:791a779d6220 347 /* Write the GIF terminator mark */
shoaib_ahmed 0:791a779d6220 348 putc(';', dest->pub.output_file);
shoaib_ahmed 0:791a779d6220 349 /* Make sure we wrote the output file OK */
shoaib_ahmed 0:791a779d6220 350 fflush(dest->pub.output_file);
shoaib_ahmed 0:791a779d6220 351 if (ferror(dest->pub.output_file))
shoaib_ahmed 0:791a779d6220 352 ERREXIT(cinfo, JERR_FILE_WRITE);
shoaib_ahmed 0:791a779d6220 353 }
shoaib_ahmed 0:791a779d6220 354
shoaib_ahmed 0:791a779d6220 355
shoaib_ahmed 0:791a779d6220 356 /*
shoaib_ahmed 0:791a779d6220 357 * The module selection routine for GIF format output.
shoaib_ahmed 0:791a779d6220 358 */
shoaib_ahmed 0:791a779d6220 359
shoaib_ahmed 0:791a779d6220 360 GLOBAL(djpeg_dest_ptr)
shoaib_ahmed 0:791a779d6220 361 jinit_write_gif (j_decompress_ptr cinfo)
shoaib_ahmed 0:791a779d6220 362 {
shoaib_ahmed 0:791a779d6220 363 gif_dest_ptr dest;
shoaib_ahmed 0:791a779d6220 364
shoaib_ahmed 0:791a779d6220 365 /* Create module interface object, fill in method pointers */
shoaib_ahmed 0:791a779d6220 366 dest = (gif_dest_ptr)
shoaib_ahmed 0:791a779d6220 367 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
shoaib_ahmed 0:791a779d6220 368 SIZEOF(gif_dest_struct));
shoaib_ahmed 0:791a779d6220 369 dest->cinfo = cinfo; /* make back link for subroutines */
shoaib_ahmed 0:791a779d6220 370 dest->pub.start_output = start_output_gif;
shoaib_ahmed 0:791a779d6220 371 dest->pub.put_pixel_rows = put_pixel_rows;
shoaib_ahmed 0:791a779d6220 372 dest->pub.finish_output = finish_output_gif;
shoaib_ahmed 0:791a779d6220 373
shoaib_ahmed 0:791a779d6220 374 if (cinfo->out_color_space != JCS_GRAYSCALE &&
shoaib_ahmed 0:791a779d6220 375 cinfo->out_color_space != JCS_RGB)
shoaib_ahmed 0:791a779d6220 376 ERREXIT(cinfo, JERR_GIF_COLORSPACE);
shoaib_ahmed 0:791a779d6220 377
shoaib_ahmed 0:791a779d6220 378 /* Force quantization if color or if > 8 bits input */
shoaib_ahmed 0:791a779d6220 379 if (cinfo->out_color_space != JCS_GRAYSCALE || cinfo->data_precision > 8) {
shoaib_ahmed 0:791a779d6220 380 /* Force quantization to at most 256 colors */
shoaib_ahmed 0:791a779d6220 381 cinfo->quantize_colors = TRUE;
shoaib_ahmed 0:791a779d6220 382 if (cinfo->desired_number_of_colors > 256)
shoaib_ahmed 0:791a779d6220 383 cinfo->desired_number_of_colors = 256;
shoaib_ahmed 0:791a779d6220 384 }
shoaib_ahmed 0:791a779d6220 385
shoaib_ahmed 0:791a779d6220 386 /* Calculate output image dimensions so we can allocate space */
shoaib_ahmed 0:791a779d6220 387 jpeg_calc_output_dimensions(cinfo);
shoaib_ahmed 0:791a779d6220 388
shoaib_ahmed 0:791a779d6220 389 if (cinfo->output_components != 1) /* safety check: just one component? */
shoaib_ahmed 0:791a779d6220 390 ERREXIT(cinfo, JERR_GIF_BUG);
shoaib_ahmed 0:791a779d6220 391
shoaib_ahmed 0:791a779d6220 392 /* Create decompressor output buffer. */
shoaib_ahmed 0:791a779d6220 393 dest->pub.buffer = (*cinfo->mem->alloc_sarray)
shoaib_ahmed 0:791a779d6220 394 ((j_common_ptr) cinfo, JPOOL_IMAGE, cinfo->output_width, (JDIMENSION) 1);
shoaib_ahmed 0:791a779d6220 395 dest->pub.buffer_height = 1;
shoaib_ahmed 0:791a779d6220 396
shoaib_ahmed 0:791a779d6220 397 return &dest->pub;
shoaib_ahmed 0:791a779d6220 398 }
shoaib_ahmed 0:791a779d6220 399
shoaib_ahmed 0:791a779d6220 400 #endif /* GIF_SUPPORTED */