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authorRalph Giles <ralph.giles@artifex.com>2005-04-24 21:31:02 +0000
committerRalph Giles <ralph.giles@artifex.com>2005-04-24 21:31:02 +0000
commita10601b87cb2bb308efb50cb2cf9ab9378b09e62 (patch)
treea16798cf9c1d9776fd3ecd8b58a794c0d3f96c79 /gs/jpeg/rdswitch.c
parentac66e082c160b2ac92a72e4c51621f9083c0b252 (diff)
Initial revision
git-svn-id: http://svn.ghostscript.com/ghostscript/trunk@5867 a1074d23-0009-0410-80fe-cf8c14f379e6
Diffstat (limited to 'gs/jpeg/rdswitch.c')
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1 files changed, 332 insertions, 0 deletions
diff --git a/gs/jpeg/rdswitch.c b/gs/jpeg/rdswitch.c
new file mode 100644
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+/*
+ * rdswitch.c
+ *
+ * Copyright (C) 1991-1996, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains routines to process some of cjpeg's more complicated
+ * command-line switches. Switches processed here are:
+ * -qtables file Read quantization tables from text file
+ * -scans file Read scan script from text file
+ * -qslots N[,N,...] Set component quantization table selectors
+ * -sample HxV[,HxV,...] Set component sampling factors
+ */
+
+#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
+#include <ctype.h> /* to declare isdigit(), isspace() */
+
+
+LOCAL(int)
+text_getc (FILE * file)
+/* Read next char, skipping over any comments (# to end of line) */
+/* A comment/newline sequence is returned as a newline */
+{
+ register int ch;
+
+ ch = getc(file);
+ if (ch == '#') {
+ do {
+ ch = getc(file);
+ } while (ch != '\n' && ch != EOF);
+ }
+ return ch;
+}
+
+
+LOCAL(boolean)
+read_text_integer (FILE * file, long * result, int * termchar)
+/* Read an unsigned decimal integer from a file, store it in result */
+/* Reads one trailing character after the integer; returns it in termchar */
+{
+ register int ch;
+ register long val;
+
+ /* Skip any leading whitespace, detect EOF */
+ do {
+ ch = text_getc(file);
+ if (ch == EOF) {
+ *termchar = ch;
+ return FALSE;
+ }
+ } while (isspace(ch));
+
+ if (! isdigit(ch)) {
+ *termchar = ch;
+ return FALSE;
+ }
+
+ val = ch - '0';
+ while ((ch = text_getc(file)) != EOF) {
+ if (! isdigit(ch))
+ break;
+ val *= 10;
+ val += ch - '0';
+ }
+ *result = val;
+ *termchar = ch;
+ return TRUE;
+}
+
+
+GLOBAL(boolean)
+read_quant_tables (j_compress_ptr cinfo, char * filename,
+ int scale_factor, boolean force_baseline)
+/* Read a set of quantization tables from the specified file.
+ * The file is plain ASCII text: decimal numbers with whitespace between.
+ * Comments preceded by '#' may be included in the file.
+ * There may be one to NUM_QUANT_TBLS tables in the file, each of 64 values.
+ * The tables are implicitly numbered 0,1,etc.
+ * NOTE: does not affect the qslots mapping, which will default to selecting
+ * table 0 for luminance (or primary) components, 1 for chrominance components.
+ * You must use -qslots if you want a different component->table mapping.
+ */
+{
+ FILE * fp;
+ int tblno, i, termchar;
+ long val;
+ unsigned int table[DCTSIZE2];
+
+ if ((fp = fopen(filename, "r")) == NULL) {
+ fprintf(stderr, "Can't open table file %s\n", filename);
+ return FALSE;
+ }
+ tblno = 0;
+
+ while (read_text_integer(fp, &val, &termchar)) { /* read 1st element of table */
+ if (tblno >= NUM_QUANT_TBLS) {
+ fprintf(stderr, "Too many tables in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+ table[0] = (unsigned int) val;
+ for (i = 1; i < DCTSIZE2; i++) {
+ if (! read_text_integer(fp, &val, &termchar)) {
+ fprintf(stderr, "Invalid table data in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+ table[i] = (unsigned int) val;
+ }
+ jpeg_add_quant_table(cinfo, tblno, table, scale_factor, force_baseline);
+ tblno++;
+ }
+
+ if (termchar != EOF) {
+ fprintf(stderr, "Non-numeric data in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+
+ fclose(fp);
+ return TRUE;
+}
+
+
+#ifdef C_MULTISCAN_FILES_SUPPORTED
+
+LOCAL(boolean)
+read_scan_integer (FILE * file, long * result, int * termchar)
+/* Variant of read_text_integer that always looks for a non-space termchar;
+ * this simplifies parsing of punctuation in scan scripts.
+ */
+{
+ register int ch;
+
+ if (! read_text_integer(file, result, termchar))
+ return FALSE;
+ ch = *termchar;
+ while (ch != EOF && isspace(ch))
+ ch = text_getc(file);
+ if (isdigit(ch)) { /* oops, put it back */
+ if (ungetc(ch, file) == EOF)
+ return FALSE;
+ ch = ' ';
+ } else {
+ /* Any separators other than ';' and ':' are ignored;
+ * this allows user to insert commas, etc, if desired.
+ */
+ if (ch != EOF && ch != ';' && ch != ':')
+ ch = ' ';
+ }
+ *termchar = ch;
+ return TRUE;
+}
+
+
+GLOBAL(boolean)
+read_scan_script (j_compress_ptr cinfo, char * filename)
+/* Read a scan script from the specified text file.
+ * Each entry in the file defines one scan to be emitted.
+ * Entries are separated by semicolons ';'.
+ * An entry contains one to four component indexes,
+ * optionally followed by a colon ':' and four progressive-JPEG parameters.
+ * The component indexes denote which component(s) are to be transmitted
+ * in the current scan. The first component has index 0.
+ * Sequential JPEG is used if the progressive-JPEG parameters are omitted.
+ * The file is free format text: any whitespace may appear between numbers
+ * and the ':' and ';' punctuation marks. Also, other punctuation (such
+ * as commas or dashes) can be placed between numbers if desired.
+ * Comments preceded by '#' may be included in the file.
+ * Note: we do very little validity checking here;
+ * jcmaster.c will validate the script parameters.
+ */
+{
+ FILE * fp;
+ int scanno, ncomps, termchar;
+ long val;
+ jpeg_scan_info * scanptr;
+#define MAX_SCANS 100 /* quite arbitrary limit */
+ jpeg_scan_info scans[MAX_SCANS];
+
+ if ((fp = fopen(filename, "r")) == NULL) {
+ fprintf(stderr, "Can't open scan definition file %s\n", filename);
+ return FALSE;
+ }
+ scanptr = scans;
+ scanno = 0;
+
+ while (read_scan_integer(fp, &val, &termchar)) {
+ if (scanno >= MAX_SCANS) {
+ fprintf(stderr, "Too many scans defined in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+ scanptr->component_index[0] = (int) val;
+ ncomps = 1;
+ while (termchar == ' ') {
+ if (ncomps >= MAX_COMPS_IN_SCAN) {
+ fprintf(stderr, "Too many components in one scan in file %s\n",
+ filename);
+ fclose(fp);
+ return FALSE;
+ }
+ if (! read_scan_integer(fp, &val, &termchar))
+ goto bogus;
+ scanptr->component_index[ncomps] = (int) val;
+ ncomps++;
+ }
+ scanptr->comps_in_scan = ncomps;
+ if (termchar == ':') {
+ if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
+ goto bogus;
+ scanptr->Ss = (int) val;
+ if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
+ goto bogus;
+ scanptr->Se = (int) val;
+ if (! read_scan_integer(fp, &val, &termchar) || termchar != ' ')
+ goto bogus;
+ scanptr->Ah = (int) val;
+ if (! read_scan_integer(fp, &val, &termchar))
+ goto bogus;
+ scanptr->Al = (int) val;
+ } else {
+ /* set non-progressive parameters */
+ scanptr->Ss = 0;
+ scanptr->Se = DCTSIZE2-1;
+ scanptr->Ah = 0;
+ scanptr->Al = 0;
+ }
+ if (termchar != ';' && termchar != EOF) {
+bogus:
+ fprintf(stderr, "Invalid scan entry format in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+ scanptr++, scanno++;
+ }
+
+ if (termchar != EOF) {
+ fprintf(stderr, "Non-numeric data in file %s\n", filename);
+ fclose(fp);
+ return FALSE;
+ }
+
+ if (scanno > 0) {
+ /* Stash completed scan list in cinfo structure.
+ * NOTE: for cjpeg's use, JPOOL_IMAGE is the right lifetime for this data,
+ * but if you want to compress multiple images you'd want JPOOL_PERMANENT.
+ */
+ scanptr = (jpeg_scan_info *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+ scanno * SIZEOF(jpeg_scan_info));
+ MEMCOPY(scanptr, scans, scanno * SIZEOF(jpeg_scan_info));
+ cinfo->scan_info = scanptr;
+ cinfo->num_scans = scanno;
+ }
+
+ fclose(fp);
+ return TRUE;
+}
+
+#endif /* C_MULTISCAN_FILES_SUPPORTED */
+
+
+GLOBAL(boolean)
+set_quant_slots (j_compress_ptr cinfo, char *arg)
+/* Process a quantization-table-selectors parameter string, of the form
+ * N[,N,...]
+ * If there are more components than parameters, the last value is replicated.
+ */
+{
+ int val = 0; /* default table # */
+ int ci;
+ char ch;
+
+ for (ci = 0; ci < MAX_COMPONENTS; ci++) {
+ if (*arg) {
+ ch = ','; /* if not set by sscanf, will be ',' */
+ if (sscanf(arg, "%d%c", &val, &ch) < 1)
+ return FALSE;
+ if (ch != ',') /* syntax check */
+ return FALSE;
+ if (val < 0 || val >= NUM_QUANT_TBLS) {
+ fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
+ NUM_QUANT_TBLS-1);
+ return FALSE;
+ }
+ cinfo->comp_info[ci].quant_tbl_no = val;
+ while (*arg && *arg++ != ',') /* advance to next segment of arg string */
+ ;
+ } else {
+ /* reached end of parameter, set remaining components to last table */
+ cinfo->comp_info[ci].quant_tbl_no = val;
+ }
+ }
+ return TRUE;
+}
+
+
+GLOBAL(boolean)
+set_sample_factors (j_compress_ptr cinfo, char *arg)
+/* Process a sample-factors parameter string, of the form
+ * HxV[,HxV,...]
+ * If there are more components than parameters, "1x1" is assumed for the rest.
+ */
+{
+ int ci, val1, val2;
+ char ch1, ch2;
+
+ for (ci = 0; ci < MAX_COMPONENTS; ci++) {
+ if (*arg) {
+ ch2 = ','; /* if not set by sscanf, will be ',' */
+ if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
+ return FALSE;
+ if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',') /* syntax check */
+ return FALSE;
+ if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
+ fprintf(stderr, "JPEG sampling factors must be 1..4\n");
+ return FALSE;
+ }
+ cinfo->comp_info[ci].h_samp_factor = val1;
+ cinfo->comp_info[ci].v_samp_factor = val2;
+ while (*arg && *arg++ != ',') /* advance to next segment of arg string */
+ ;
+ } else {
+ /* reached end of parameter, set remaining components to 1x1 sampling */
+ cinfo->comp_info[ci].h_samp_factor = 1;
+ cinfo->comp_info[ci].v_samp_factor = 1;
+ }
+ }
+ return TRUE;
+}