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)
text_getc(FILE * file)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)
read_text_integer(FILE * file,long * result,int * termchar)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)
read_quant_tables(j_compress_ptr cinfo,char * filename,int scale_factor,boolean force_baseline)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)
read_scan_integer(FILE * file,long * result,int * termchar)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)
read_scan_script(j_compress_ptr cinfo,char * filename)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)
set_quant_slots(j_compress_ptr cinfo,char * arg)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)
set_sample_factors(j_compress_ptr cinfo,char * arg)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 }
333