dll/3rdparty/libjpeg/rdswitch.c

   1 /*
   2  * rdswitch.c
   3  *
   4  * Copyright (C) 1991-1996, Thomas G. Lane.
   5  * This file is part of the Independent JPEG Group's software.
   6  * For conditions of distribution and use, see the accompanying README file.
   7  *
   8  * This file contains routines to process some of cjpeg's more complicated
   9  * command-line switches.  Switches processed here are:
  10  *      -qtables file           Read quantization tables from text file
  11  *      -scans file             Read scan script from text file
  12  *      -qslots N[,N,...]       Set component quantization table selectors
  13  *      -sample HxV[,HxV,...]   Set component sampling factors
  14  */
  15
  16 #include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */
  17 #include <ctype.h>              /* to declare isdigit(), isspace() */
  18
  19
  20 LOCAL(int)
  21 text_getc (FILE * file)
  22 /* Read next char, skipping over any comments (# to end of line) */
  23 /* A comment/newline sequence is returned as a newline */
  24 {
  25   register int ch;
  26
  27   ch = getc(file);
  28   if (ch == '#') {
  29     do {
  30       ch = getc(file);
  31     } while (ch != '\n' && ch != EOF);
  32   }
  33   return ch;
  34 }
  35
  36
  37 LOCAL(boolean)
  38 read_text_integer (FILE * file, long * result, int * termchar)
  39 /* Read an unsigned decimal integer from a file, store it in result */
  40 /* Reads one trailing character after the integer; returns it in termchar */
  41 {
  42   register int ch;
  43   register long val;
  44
  45   /* Skip any leading whitespace, detect EOF */
  46   do {
  47     ch = text_getc(file);
  48     if (ch == EOF) {
  49       *termchar = ch;
  50       return FALSE;
  51     }
  52   } while (isspace(ch));
  53
  54   if (! isdigit(ch)) {
  55     *termchar = ch;
  56     return FALSE;
  57   }
  58
  59   val = ch - '0';
  60   while ((ch = text_getc(file)) != EOF) {
  61     if (! isdigit(ch))
  62       break;
  63     val *= 10;
  64     val += ch - '0';
  65   }
  66   *result = val;
  67   *termchar = ch;
  68   return TRUE;
  69 }
  70
  71
  72 GLOBAL(boolean)
  73 read_quant_tables (j_compress_ptr cinfo, char * filename,
  74                    int scale_factor, boolean force_baseline)
  75 /* Read a set of quantization tables from the specified file.
  76  * The file is plain ASCII text: decimal numbers with whitespace between.
  77  * Comments preceded by '#' may be included in the file.
  78  * There may be one to NUM_QUANT_TBLS tables in the file, each of 64 values.
  79  * The tables are implicitly numbered 0,1,etc.
  80  * NOTE: does not affect the qslots mapping, which will default to selecting
  81  * table 0 for luminance (or primary) components, 1 for chrominance components.
  82  * You must use -qslots if you want a different component->table mapping.
  83  */
  84 {
  85   FILE * fp;
  86   int tblno, i, termchar;
  87   long val;
  88   unsigned int table[DCTSIZE2];
  89
  90   if ((fp = fopen(filename, "r")) == NULL) {
  91     fprintf(stderr, "Can't open table file %s\n", filename);
  92     return FALSE;
  93   }
  94   tblno = 0;
  95
  96   while (read_text_integer(fp, &val, &termchar)) { /* read 1st element of table */
  97     if (tblno >= NUM_QUANT_TBLS) {
  98       fprintf(stderr, "Too many tables in file %s\n", filename);
  99       fclose(fp);
 100       return FALSE;
 101     }
 102     table[0] = (unsigned int) val;
 103     for (i = 1; i < DCTSIZE2; i++) {
 104       if (! read_text_integer(fp, &val, &termchar)) {
 105         fprintf(stderr, "Invalid table data in file %s\n", filename);
 106         fclose(fp);
 107         return FALSE;
 108       }
 109       table[i] = (unsigned int) val;
 110     }
 111     jpeg_add_quant_table(cinfo, tblno, table, scale_factor, force_baseline);
 112     tblno++;
 113   }
 114
 115   if (termchar != EOF) {
 116     fprintf(stderr, "Non-numeric data in file %s\n", filename);
 117     fclose(fp);
 118     return FALSE;
 119   }
 120
 121   fclose(fp);
 122   return TRUE;
 123 }
 124
 125
 126 #ifdef C_MULTISCAN_FILES_SUPPORTED
 127
 128 LOCAL(boolean)
 129 read_scan_integer (FILE * file, long * result, int * termchar)
 130 /* Variant of read_text_integer that always looks for a non-space termchar;
 131  * this simplifies parsing of punctuation in scan scripts.
 132  */
 133 {
 134   register int ch;
 135
 136   if (! read_text_integer(file, result, termchar))
 137     return FALSE;
 138   ch = *termchar;
 139   while (ch != EOF && isspace(ch))
 140     ch = text_getc(file);
 141   if (isdigit(ch)) {            /* oops, put it back */
 142     if (ungetc(ch, file) == EOF)
 143       return FALSE;
 144     ch = ' ';
 145   } else {
 146     /* Any separators other than ';' and ':' are ignored;
 147      * this allows user to insert commas, etc, if desired.
 148      */
 149     if (ch != EOF && ch != ';' && ch != ':')
 150       ch = ' ';
 151   }
 152   *termchar = ch;
 153   return TRUE;
 154 }
 155
 156
 157 GLOBAL(boolean)
 158 read_scan_script (j_compress_ptr cinfo, char * filename)
 159 /* Read a scan script from the specified text file.
 160  * Each entry in the file defines one scan to be emitted.
 161  * Entries are separated by semicolons ';'.
 162  * An entry contains one to four component indexes,
 163  * optionally followed by a colon ':' and four progressive-JPEG parameters.
 164  * The component indexes denote which component(s) are to be transmitted
 165  * in the current scan.  The first component has index 0.
 166  * Sequential JPEG is used if the progressive-JPEG parameters are omitted.
 167  * The file is free format text: any whitespace may appear between numbers
 168  * and the ':' and ';' punctuation marks.  Also, other punctuation (such
 169  * as commas or dashes) can be placed between numbers if desired.
 170  * Comments preceded by '#' may be included in the file.
 171  * Note: we do very little validity checking here;
 172  * jcmaster.c will validate the script parameters.
 173  */
 174 {
 175   FILE * fp;
 176   int scanno, ncomps, termchar;
 177   long val;
 178   jpeg_scan_info * scanptr;
 179 #define MAX_SCANS  100          /* quite arbitrary limit */
 180   jpeg_scan_info scans[MAX_SCANS];
 181
 182   if ((fp = fopen(filename, "r")) == NULL) {
 183     fprintf(stderr, "Can't open scan definition file %s\n", filename);
 184     return FALSE;
 185   }
 186   scanptr = scans;
 187   scanno = 0;
 188
 189   while (read_scan_integer(fp, &val, &termchar)) {
 190     if (scanno >= MAX_SCANS) {
 191       fprintf(stderr, "Too many scans defined in file %s\n", filename);
 192       fclose(fp);
 193       return FALSE;
 194     }
 195     scanptr->component_index[0] = (int) val;
 196     ncomps = 1;
 197     while (termchar == ' ') {
 198       if (ncomps >= MAX_COMPS_IN_SCAN) {
 199         fprintf(stderr, "Too many components in one scan in file %s\n",
 200                 filename);
 201         fclose(fp);
 202         return FALSE;
 203       }
 204       if (! read_scan_integer(fp, &val, &termchar))
 205         goto bogus;
 206       scanptr->component_index[ncomps] = (int) val;
 207       ncomps++;
 208     }
 209     scanptr->comps_in_scan = ncomps;
 210     if (termchar == ':') {
 211       if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
 212         goto bogus;
 213       scanptr->Ss = (int) val;
 214       if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
 215         goto bogus;
 216       scanptr->Se = (int) val;
 217       if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
 218         goto bogus;
 219       scanptr->Ah = (int) val;
 220       if (! read_scan_integer(fp, &val, &termchar))
 221         goto bogus;
 222       scanptr->Al = (int) val;
 223     } else {
 224       /* set non-progressive parameters */
 225       scanptr->Ss = 0;
 226       scanptr->Se = DCTSIZE2-1;
 227       scanptr->Ah = 0;
 228       scanptr->Al = 0;
 229     }
 230     if (termchar != ';' && termchar != EOF) {
 231 bogus:
 232       fprintf(stderr, "Invalid scan entry format in file %s\n", filename);
 233       fclose(fp);
 234       return FALSE;
 235     }
 236     scanptr++, scanno++;
 237   }
 238
 239   if (termchar != EOF) {
 240     fprintf(stderr, "Non-numeric data in file %s\n", filename);
 241     fclose(fp);
 242     return FALSE;
 243   }
 244
 245   if (scanno > 0) {
 246     /* Stash completed scan list in cinfo structure.
 247      * NOTE: for cjpeg's use, JPOOL_IMAGE is the right lifetime for this data,
 248      * but if you want to compress multiple images you'd want JPOOL_PERMANENT.
 249      */
 250     scanptr = (jpeg_scan_info *)
 251       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
 252                                   scanno * SIZEOF(jpeg_scan_info));
 253     MEMCOPY(scanptr, scans, scanno * SIZEOF(jpeg_scan_info));
 254     cinfo->scan_info = scanptr;
 255     cinfo->num_scans = scanno;
 256   }
 257
 258   fclose(fp);
 259   return TRUE;
 260 }
 261
 262 #endif /* C_MULTISCAN_FILES_SUPPORTED */
 263
 264
 265 GLOBAL(boolean)
 266 set_quant_slots (j_compress_ptr cinfo, char *arg)
 267 /* Process a quantization-table-selectors parameter string, of the form
 268  *     N[,N,...]
 269  * If there are more components than parameters, the last value is replicated.
 270  */
 271 {
 272   int val = 0;                  /* default table # */
 273   int ci;
 274   char ch;
 275
 276   for (ci = 0; ci < MAX_COMPONENTS; ci++) {
 277     if (*arg) {
 278       ch = ',';                 /* if not set by sscanf, will be ',' */
 279       if (sscanf(arg, "%d%c", &val, &ch) < 1)
 280         return FALSE;
 281       if (ch != ',')            /* syntax check */
 282         return FALSE;
 283       if (val < 0 || val >= NUM_QUANT_TBLS) {
 284         fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
 285                 NUM_QUANT_TBLS-1);
 286         return FALSE;
 287       }
 288       cinfo->comp_info[ci].quant_tbl_no = val;
 289       while (*arg && *arg++ != ',') /* advance to next segment of arg string */
 290         ;
 291     } else {
 292       /* reached end of parameter, set remaining components to last table */
 293       cinfo->comp_info[ci].quant_tbl_no = val;
 294     }
 295   }
 296   return TRUE;
 297 }
 298
 299
 300 GLOBAL(boolean)
 301 set_sample_factors (j_compress_ptr cinfo, char *arg)
 302 /* Process a sample-factors parameter string, of the form
 303  *     HxV[,HxV,...]
 304  * If there are more components than parameters, "1x1" is assumed for the rest.
 305  */
 306 {
 307   int ci, val1, val2;
 308   char ch1, ch2;
 309
 310   for (ci = 0; ci < MAX_COMPONENTS; ci++) {
 311     if (*arg) {
 312       ch2 = ',';                /* if not set by sscanf, will be ',' */
 313       if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
 314         return FALSE;
 315       if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',') /* syntax check */
 316         return FALSE;
 317       if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
 318         fprintf(stderr, "JPEG sampling factors must be 1..4\n");
 319         return FALSE;
 320       }
 321       cinfo->comp_info[ci].h_samp_factor = val1;
 322       cinfo->comp_info[ci].v_samp_factor = val2;
 323       while (*arg && *arg++ != ',') /* advance to next segment of arg string */
 324         ;
 325     } else {
 326       /* reached end of parameter, set remaining components to 1x1 sampling */
 327       cinfo->comp_info[ci].h_samp_factor = 1;
 328       cinfo->comp_info[ci].v_samp_factor = 1;
 329     }
 330   }
 331   return TRUE;
 332 }