4 * Copyright (C) 1991-1996, Thomas G. Lane.
5 * Copyright (C) 2010, D. R. Commander.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
9 * This file contains routines to process some of cjpeg's more complicated
10 * command-line switches. Switches processed here are:
11 * -qtables file Read quantization tables from text file
12 * -scans file Read scan script from text file
13 * -quality N[,N,...] Set quality ratings
14 * -qslots N[,N,...] Set component quantization table selectors
15 * -sample HxV[,HxV,...] Set component sampling factors
18 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
19 #include <ctype.h> /* to declare isdigit(), isspace() */
23 text_getc (FILE * file)
24 /* Read next char, skipping over any comments (# to end of line) */
25 /* A comment/newline sequence is returned as a newline */
33 } while (ch != '\n' && ch != EOF);
40 read_text_integer (FILE * file, long * result, int * termchar)
41 /* Read an unsigned decimal integer from a file, store it in result */
42 /* Reads one trailing character after the integer; returns it in termchar */
47 /* Skip any leading whitespace, detect EOF */
54 } while (isspace(ch));
62 while ((ch = text_getc(file)) != EOF) {
74 #if JPEG_LIB_VERSION < 70
75 static int q_scale_factor[NUM_QUANT_TBLS] = {100, 100, 100, 100};
79 read_quant_tables (j_compress_ptr cinfo, char * filename, boolean force_baseline)
80 /* Read a set of quantization tables from the specified file.
81 * The file is plain ASCII text: decimal numbers with whitespace between.
82 * Comments preceded by '#' may be included in the file.
83 * There may be one to NUM_QUANT_TBLS tables in the file, each of 64 values.
84 * The tables are implicitly numbered 0,1,etc.
85 * NOTE: does not affect the qslots mapping, which will default to selecting
86 * table 0 for luminance (or primary) components, 1 for chrominance components.
87 * You must use -qslots if you want a different component->table mapping.
91 int tblno, i, termchar;
93 unsigned int table[DCTSIZE2];
95 if ((fp = fopen(filename, "r")) == NULL) {
96 fprintf(stderr, "Can't open table file %s\n", filename);
101 while (read_text_integer(fp, &val, &termchar)) { /* read 1st element of table */
102 if (tblno >= NUM_QUANT_TBLS) {
103 fprintf(stderr, "Too many tables in file %s\n", filename);
107 table[0] = (unsigned int) val;
108 for (i = 1; i < DCTSIZE2; i++) {
109 if (! read_text_integer(fp, &val, &termchar)) {
110 fprintf(stderr, "Invalid table data in file %s\n", filename);
114 table[i] = (unsigned int) val;
116 #if JPEG_LIB_VERSION >= 70
117 jpeg_add_quant_table(cinfo, tblno, table, cinfo->q_scale_factor[tblno],
120 jpeg_add_quant_table(cinfo, tblno, table, q_scale_factor[tblno],
126 if (termchar != EOF) {
127 fprintf(stderr, "Non-numeric data in file %s\n", filename);
137 #ifdef C_MULTISCAN_FILES_SUPPORTED
140 read_scan_integer (FILE * file, long * result, int * termchar)
141 /* Variant of read_text_integer that always looks for a non-space termchar;
142 * this simplifies parsing of punctuation in scan scripts.
147 if (! read_text_integer(file, result, termchar))
150 while (ch != EOF && isspace(ch))
151 ch = text_getc(file);
152 if (isdigit(ch)) { /* oops, put it back */
153 if (ungetc(ch, file) == EOF)
157 /* Any separators other than ';' and ':' are ignored;
158 * this allows user to insert commas, etc, if desired.
160 if (ch != EOF && ch != ';' && ch != ':')
169 read_scan_script (j_compress_ptr cinfo, char * filename)
170 /* Read a scan script from the specified text file.
171 * Each entry in the file defines one scan to be emitted.
172 * Entries are separated by semicolons ';'.
173 * An entry contains one to four component indexes,
174 * optionally followed by a colon ':' and four progressive-JPEG parameters.
175 * The component indexes denote which component(s) are to be transmitted
176 * in the current scan. The first component has index 0.
177 * Sequential JPEG is used if the progressive-JPEG parameters are omitted.
178 * The file is free format text: any whitespace may appear between numbers
179 * and the ':' and ';' punctuation marks. Also, other punctuation (such
180 * as commas or dashes) can be placed between numbers if desired.
181 * Comments preceded by '#' may be included in the file.
182 * Note: we do very little validity checking here;
183 * jcmaster.c will validate the script parameters.
187 int scanno, ncomps, termchar;
189 jpeg_scan_info * scanptr;
190 #define MAX_SCANS 100 /* quite arbitrary limit */
191 jpeg_scan_info scans[MAX_SCANS];
193 if ((fp = fopen(filename, "r")) == NULL) {
194 fprintf(stderr, "Can't open scan definition file %s\n", filename);
200 while (read_scan_integer(fp, &val, &termchar)) {
201 if (scanno >= MAX_SCANS) {
202 fprintf(stderr, "Too many scans defined in file %s\n", filename);
206 scanptr->component_index[0] = (int) val;
208 while (termchar == ' ') {
209 if (ncomps >= MAX_COMPS_IN_SCAN) {
210 fprintf(stderr, "Too many components in one scan in file %s\n",
215 if (! read_scan_integer(fp, &val, &termchar))
217 scanptr->component_index[ncomps] = (int) val;
220 scanptr->comps_in_scan = ncomps;
221 if (termchar == ':') {
222 if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
224 scanptr->Ss = (int) val;
225 if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
227 scanptr->Se = (int) val;
228 if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
230 scanptr->Ah = (int) val;
231 if (! read_scan_integer(fp, &val, &termchar))
233 scanptr->Al = (int) val;
235 /* set non-progressive parameters */
237 scanptr->Se = DCTSIZE2-1;
241 if (termchar != ';' && termchar != EOF) {
243 fprintf(stderr, "Invalid scan entry format in file %s\n", filename);
250 if (termchar != EOF) {
251 fprintf(stderr, "Non-numeric data in file %s\n", filename);
257 /* Stash completed scan list in cinfo structure.
258 * NOTE: for cjpeg's use, JPOOL_IMAGE is the right lifetime for this data,
259 * but if you want to compress multiple images you'd want JPOOL_PERMANENT.
261 scanptr = (jpeg_scan_info *)
262 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
263 scanno * SIZEOF(jpeg_scan_info));
264 MEMCOPY(scanptr, scans, scanno * SIZEOF(jpeg_scan_info));
265 cinfo->scan_info = scanptr;
266 cinfo->num_scans = scanno;
273 #endif /* C_MULTISCAN_FILES_SUPPORTED */
276 #if JPEG_LIB_VERSION < 70
277 /* These are the sample quantization tables given in JPEG spec section K.1.
278 * The spec says that the values given produce "good" quality, and
279 * when divided by 2, "very good" quality.
281 static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {
282 16, 11, 10, 16, 24, 40, 51, 61,
283 12, 12, 14, 19, 26, 58, 60, 55,
284 14, 13, 16, 24, 40, 57, 69, 56,
285 14, 17, 22, 29, 51, 87, 80, 62,
286 18, 22, 37, 56, 68, 109, 103, 77,
287 24, 35, 55, 64, 81, 104, 113, 92,
288 49, 64, 78, 87, 103, 121, 120, 101,
289 72, 92, 95, 98, 112, 100, 103, 99
291 static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {
292 17, 18, 24, 47, 99, 99, 99, 99,
293 18, 21, 26, 66, 99, 99, 99, 99,
294 24, 26, 56, 99, 99, 99, 99, 99,
295 47, 66, 99, 99, 99, 99, 99, 99,
296 99, 99, 99, 99, 99, 99, 99, 99,
297 99, 99, 99, 99, 99, 99, 99, 99,
298 99, 99, 99, 99, 99, 99, 99, 99,
299 99, 99, 99, 99, 99, 99, 99, 99
304 jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline)
306 jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
307 q_scale_factor[0], force_baseline);
308 jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
309 q_scale_factor[1], force_baseline);
315 set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline)
316 /* Process a quality-ratings parameter string, of the form
318 * If there are more q-table slots than parameters, the last value is replicated.
321 int val = 75; /* default value */
325 for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
327 ch = ','; /* if not set by sscanf, will be ',' */
328 if (sscanf(arg, "%d%c", &val, &ch) < 1)
330 if (ch != ',') /* syntax check */
332 /* Convert user 0-100 rating to percentage scaling */
333 #if JPEG_LIB_VERSION >= 70
334 cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
336 q_scale_factor[tblno] = jpeg_quality_scaling(val);
338 while (*arg && *arg++ != ',') /* advance to next segment of arg string */
341 /* reached end of parameter, set remaining factors to last value */
342 #if JPEG_LIB_VERSION >= 70
343 cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
345 q_scale_factor[tblno] = jpeg_quality_scaling(val);
349 jpeg_default_qtables(cinfo, force_baseline);
355 set_quant_slots (j_compress_ptr cinfo, char *arg)
356 /* Process a quantization-table-selectors parameter string, of the form
358 * If there are more components than parameters, the last value is replicated.
361 int val = 0; /* default table # */
365 for (ci = 0; ci < MAX_COMPONENTS; ci++) {
367 ch = ','; /* if not set by sscanf, will be ',' */
368 if (sscanf(arg, "%d%c", &val, &ch) < 1)
370 if (ch != ',') /* syntax check */
372 if (val < 0 || val >= NUM_QUANT_TBLS) {
373 fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
377 cinfo->comp_info[ci].quant_tbl_no = val;
378 while (*arg && *arg++ != ',') /* advance to next segment of arg string */
381 /* reached end of parameter, set remaining components to last table */
382 cinfo->comp_info[ci].quant_tbl_no = val;
390 set_sample_factors (j_compress_ptr cinfo, char *arg)
391 /* Process a sample-factors parameter string, of the form
393 * If there are more components than parameters, "1x1" is assumed for the rest.
399 for (ci = 0; ci < MAX_COMPONENTS; ci++) {
401 ch2 = ','; /* if not set by sscanf, will be ',' */
402 if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
404 if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',') /* syntax check */
406 if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
407 fprintf(stderr, "JPEG sampling factors must be 1..4\n");
410 cinfo->comp_info[ci].h_samp_factor = val1;
411 cinfo->comp_info[ci].v_samp_factor = val2;
412 while (*arg && *arg++ != ',') /* advance to next segment of arg string */
415 /* reached end of parameter, set remaining components to 1x1 sampling */
416 cinfo->comp_info[ci].h_samp_factor = 1;
417 cinfo->comp_info[ci].v_samp_factor = 1;