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.
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
* -quality N[,N,...] Set quality ratings
13
* -qslots N[,N,...] Set component quantization table selectors
14
* -sample HxV[,HxV,...] Set component sampling factors
17
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
18
#include <ctype.h> /* to declare isdigit(), isspace() */
22
text_getc (FILE * file)
23
/* Read next char, skipping over any comments (# to end of line) */
24
/* A comment/newline sequence is returned as a newline */
32
} while (ch != '\n' && ch != EOF);
39
read_text_integer (FILE * file, long * result, int * termchar)
40
/* Read an unsigned decimal integer from a file, store it in result */
41
/* Reads one trailing character after the integer; returns it in termchar */
46
/* Skip any leading whitespace, detect EOF */
53
} while (isspace(ch));
61
while ((ch = text_getc(file)) != EOF) {
74
read_quant_tables (j_compress_ptr cinfo, char * filename, 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.
86
int tblno, i, termchar;
88
unsigned int table[DCTSIZE2];
90
if ((fp = fopen(filename, "r")) == NULL) {
91
fprintf(stderr, "Can't open table file %s\n", filename);
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);
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);
109
table[i] = (unsigned int) val;
111
jpeg_add_quant_table(cinfo, tblno, table, cinfo->q_scale_factor[tblno],
116
if (termchar != EOF) {
117
fprintf(stderr, "Non-numeric data in file %s\n", filename);
127
#ifdef C_MULTISCAN_FILES_SUPPORTED
130
read_scan_integer (FILE * file, long * result, int * termchar)
131
/* Variant of read_text_integer that always looks for a non-space termchar;
132
* this simplifies parsing of punctuation in scan scripts.
137
if (! read_text_integer(file, result, termchar))
140
while (ch != EOF && isspace(ch))
141
ch = text_getc(file);
142
if (isdigit(ch)) { /* oops, put it back */
143
if (ungetc(ch, file) == EOF)
147
/* Any separators other than ';' and ':' are ignored;
148
* this allows user to insert commas, etc, if desired.
150
if (ch != EOF && ch != ';' && ch != ':')
159
read_scan_script (j_compress_ptr cinfo, char * filename)
160
/* Read a scan script from the specified text file.
161
* Each entry in the file defines one scan to be emitted.
162
* Entries are separated by semicolons ';'.
163
* An entry contains one to four component indexes,
164
* optionally followed by a colon ':' and four progressive-JPEG parameters.
165
* The component indexes denote which component(s) are to be transmitted
166
* in the current scan. The first component has index 0.
167
* Sequential JPEG is used if the progressive-JPEG parameters are omitted.
168
* The file is free format text: any whitespace may appear between numbers
169
* and the ':' and ';' punctuation marks. Also, other punctuation (such
170
* as commas or dashes) can be placed between numbers if desired.
171
* Comments preceded by '#' may be included in the file.
172
* Note: we do very little validity checking here;
173
* jcmaster.c will validate the script parameters.
177
int scanno, ncomps, termchar;
179
jpeg_scan_info * scanptr;
180
#define MAX_SCANS 100 /* quite arbitrary limit */
181
jpeg_scan_info scans[MAX_SCANS];
183
if ((fp = fopen(filename, "r")) == NULL) {
184
fprintf(stderr, "Can't open scan definition file %s\n", filename);
190
while (read_scan_integer(fp, &val, &termchar)) {
191
if (scanno >= MAX_SCANS) {
192
fprintf(stderr, "Too many scans defined in file %s\n", filename);
196
scanptr->component_index[0] = (int) val;
198
while (termchar == ' ') {
199
if (ncomps >= MAX_COMPS_IN_SCAN) {
200
fprintf(stderr, "Too many components in one scan in file %s\n",
205
if (! read_scan_integer(fp, &val, &termchar))
207
scanptr->component_index[ncomps] = (int) val;
210
scanptr->comps_in_scan = ncomps;
211
if (termchar == ':') {
212
if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
214
scanptr->Ss = (int) val;
215
if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
217
scanptr->Se = (int) val;
218
if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
220
scanptr->Ah = (int) val;
221
if (! read_scan_integer(fp, &val, &termchar))
223
scanptr->Al = (int) val;
225
/* set non-progressive parameters */
227
scanptr->Se = DCTSIZE2-1;
231
if (termchar != ';' && termchar != EOF) {
233
fprintf(stderr, "Invalid scan entry format in file %s\n", filename);
240
if (termchar != EOF) {
241
fprintf(stderr, "Non-numeric data in file %s\n", filename);
247
/* Stash completed scan list in cinfo structure.
248
* NOTE: for cjpeg's use, JPOOL_IMAGE is the right lifetime for this data,
249
* but if you want to compress multiple images you'd want JPOOL_PERMANENT.
251
scanptr = (jpeg_scan_info *)
252
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
253
scanno * SIZEOF(jpeg_scan_info));
254
MEMCOPY(scanptr, scans, scanno * SIZEOF(jpeg_scan_info));
255
cinfo->scan_info = scanptr;
256
cinfo->num_scans = scanno;
263
#endif /* C_MULTISCAN_FILES_SUPPORTED */
267
set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline)
268
/* Process a quality-ratings parameter string, of the form
270
* If there are more q-table slots than parameters, the last value is replicated.
273
int val = 75; /* default value */
277
for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
279
ch = ','; /* if not set by sscanf, will be ',' */
280
if (sscanf(arg, "%d%c", &val, &ch) < 1)
282
if (ch != ',') /* syntax check */
284
/* Convert user 0-100 rating to percentage scaling */
285
cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
286
while (*arg && *arg++ != ',') /* advance to next segment of arg string */
289
/* reached end of parameter, set remaining factors to last value */
290
cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
293
jpeg_default_qtables(cinfo, force_baseline);
299
set_quant_slots (j_compress_ptr cinfo, char *arg)
300
/* Process a quantization-table-selectors parameter string, of the form
302
* If there are more components than parameters, the last value is replicated.
305
int val = 0; /* default table # */
309
for (ci = 0; ci < MAX_COMPONENTS; ci++) {
311
ch = ','; /* if not set by sscanf, will be ',' */
312
if (sscanf(arg, "%d%c", &val, &ch) < 1)
314
if (ch != ',') /* syntax check */
316
if (val < 0 || val >= NUM_QUANT_TBLS) {
317
fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
321
cinfo->comp_info[ci].quant_tbl_no = val;
322
while (*arg && *arg++ != ',') /* advance to next segment of arg string */
325
/* reached end of parameter, set remaining components to last table */
326
cinfo->comp_info[ci].quant_tbl_no = val;
334
set_sample_factors (j_compress_ptr cinfo, char *arg)
335
/* Process a sample-factors parameter string, of the form
337
* If there are more components than parameters, "1x1" is assumed for the rest.
343
for (ci = 0; ci < MAX_COMPONENTS; ci++) {
345
ch2 = ','; /* if not set by sscanf, will be ',' */
346
if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
348
if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',') /* syntax check */
350
if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
351
fprintf(stderr, "JPEG sampling factors must be 1..4\n");
354
cinfo->comp_info[ci].h_samp_factor = val1;
355
cinfo->comp_info[ci].v_samp_factor = val2;
356
while (*arg && *arg++ != ',') /* advance to next segment of arg string */
359
/* reached end of parameter, set remaining components to 1x1 sampling */
360
cinfo->comp_info[ci].h_samp_factor = 1;
361
cinfo->comp_info[ci].v_samp_factor = 1;