diff options
author | Ralph Giles <ralph.giles@artifex.com> | 2005-04-24 21:31:02 +0000 |
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committer | Ralph Giles <ralph.giles@artifex.com> | 2005-04-24 21:31:02 +0000 |
commit | a10601b87cb2bb308efb50cb2cf9ab9378b09e62 (patch) | |
tree | a16798cf9c1d9776fd3ecd8b58a794c0d3f96c79 /gs/jpeg/rdswitch.c | |
parent | ac66e082c160b2ac92a72e4c51621f9083c0b252 (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')
-rw-r--r-- | gs/jpeg/rdswitch.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/gs/jpeg/rdswitch.c b/gs/jpeg/rdswitch.c new file mode 100644 index 000000000..4f4bb4f58 --- /dev/null +++ b/gs/jpeg/rdswitch.c @@ -0,0 +1,332 @@ +/* + * 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; +} |