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;