/* 
 * 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; 
} 
