621 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			621 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
/*
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 *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
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 *  copyright (C) 1999-2019 by Willem van Schaik <willem at schaik dot com>
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 *
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 *  This software is released under the MIT license. For conditions of
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 *  distribution and use, see the LICENSE file part of this package.
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <fcntl.h>
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#ifndef BOOL
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#define BOOL unsigned char
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#endif
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#ifndef TRUE
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#define TRUE (BOOL) 1
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#endif
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#ifndef FALSE
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#define FALSE (BOOL) 0
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#endif
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/* make pnm2png verbose so we can find problems (needs to be before png.h) */
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#ifndef PNG_DEBUG
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#define PNG_DEBUG 0
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#endif
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#include "png.h"
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/* function prototypes */
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int main (int argc, char *argv[]);
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void usage ();
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BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
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              BOOL interlace, BOOL alpha);
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void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size);
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png_uint_32 get_data (FILE *pnm_file, int depth);
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png_uint_32 get_value (FILE *pnm_file, int depth);
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/*
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 *  main
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 */
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int main (int argc, char *argv[])
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{
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  FILE *fp_rd = stdin;
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  FILE *fp_al = NULL;
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  FILE *fp_wr = stdout;
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  BOOL interlace = FALSE;
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  BOOL alpha = FALSE;
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  int argi;
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  for (argi = 1; argi < argc; argi++)
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  {
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    if (argv[argi][0] == '-')
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    {
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      switch (argv[argi][1])
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      {
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        case 'i':
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          interlace = TRUE;
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          break;
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        case 'a':
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          alpha = TRUE;
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          argi++;
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          if ((fp_al = fopen (argv[argi], "rb")) == NULL)
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          {
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            fprintf (stderr, "PNM2PNG\n");
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            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",
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                     argv[argi]);
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            exit (1);
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          }
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          break;
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        case 'h':
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        case '?':
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          usage ();
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          exit (0);
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          break;
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        default:
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          fprintf (stderr, "PNM2PNG\n");
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          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
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          usage ();
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          exit (1);
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          break;
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      } /* end switch */
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    }
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    else if (fp_rd == stdin)
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    {
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      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
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      {
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        fprintf (stderr, "PNM2PNG\n");
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        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
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        exit (1);
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      }
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    }
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    else if (fp_wr == stdout)
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    {
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      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
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      {
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        fprintf (stderr, "PNM2PNG\n");
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        fprintf (stderr, "Error:  cannot create PNG-file %s\n", argv[argi]);
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        exit (1);
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      }
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    }
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    else
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    {
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      fprintf (stderr, "PNM2PNG\n");
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      fprintf (stderr, "Error:  too many parameters\n");
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      usage ();
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      exit (1);
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    }
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  } /* end for */
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#if defined(O_BINARY) && (O_BINARY != 0)
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  /* set stdin/stdout to binary,
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   * we're reading the PNM always! in binary format
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   */
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  if (fp_rd == stdin)
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    setmode (fileno (stdin), O_BINARY);
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  if (fp_wr == stdout)
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    setmode (fileno (stdout), O_BINARY);
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#endif
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  /* call the conversion program itself */
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  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
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  {
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    fprintf (stderr, "PNM2PNG\n");
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    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
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    exit (1);
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  }
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  /* close input file */
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  fclose (fp_rd);
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  /* close output file */
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  fclose (fp_wr);
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  /* close alpha file */
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  if (alpha)
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    fclose (fp_al);
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  return 0;
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}
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/*
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 *  usage
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 */
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void usage ()
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{
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  fprintf (stderr, "PNM2PNG\n");
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  fprintf (stderr, "   by Willem van Schaik, 1999\n");
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  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");
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  fprintf (stderr, "   or:  ... | pnm2png [options]\n");
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  fprintf (stderr, "Options:\n");
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  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");
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  fprintf (stderr,
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      "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
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  fprintf (stderr, "   -h | -?  print this help-information\n");
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}
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/*
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 *  pnm2png
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 */
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BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
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              BOOL interlace, BOOL alpha)
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{
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  png_struct    *png_ptr = NULL;
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  png_info      *info_ptr = NULL;
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  png_byte      *png_pixels = NULL;
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  png_byte      **row_pointers = NULL;
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  png_byte      *pix_ptr = NULL;
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  volatile png_uint_32 row_bytes;
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  char          type_token[16];
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  char          width_token[16];
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  char          height_token[16];
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  char          maxval_token[16];
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  volatile int  color_type = 1;
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  unsigned long ul_width = 0, ul_alpha_width = 0;
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  unsigned long ul_height = 0, ul_alpha_height = 0;
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  unsigned long ul_maxval = 0;
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  volatile png_uint_32 width = 0, height = 0;
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  volatile png_uint_32 alpha_width = 0, alpha_height = 0;
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  png_uint_32   maxval;
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  volatile int  bit_depth = 0;
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  int           channels = 0;
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  int           alpha_depth = 0;
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  int           alpha_present = 0;
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  int           row, col;
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  BOOL          raw, alpha_raw = FALSE;
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
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  BOOL          packed_bitmap = FALSE;
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#endif
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  png_uint_32   tmp16;
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  int           i;
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  /* read header of PNM file */
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  get_token (pnm_file, type_token, sizeof (type_token));
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  if (type_token[0] != 'P')
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  {
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    return FALSE;
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  }
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  else if ((type_token[1] == '1') || (type_token[1] == '4'))
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  {
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
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    raw = (type_token[1] == '4');
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    color_type = PNG_COLOR_TYPE_GRAY;
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    get_token (pnm_file, width_token, sizeof (width_token));
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    sscanf (width_token, "%lu", &ul_width);
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    width = (png_uint_32) ul_width;
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    get_token (pnm_file, height_token, sizeof (height_token));
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    sscanf (height_token, "%lu", &ul_height);
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    height = (png_uint_32) ul_height;
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    bit_depth = 1;
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    packed_bitmap = TRUE;
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#else
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    fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and\n");
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    fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
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    return FALSE;
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#endif
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  }
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  else if ((type_token[1] == '2') || (type_token[1] == '5'))
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  {
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    raw = (type_token[1] == '5');
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    color_type = PNG_COLOR_TYPE_GRAY;
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    get_token (pnm_file, width_token, sizeof (width_token));
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    sscanf (width_token, "%lu", &ul_width);
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    width = (png_uint_32) ul_width;
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    get_token (pnm_file, height_token, sizeof (height_token));
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    sscanf (height_token, "%lu", &ul_height);
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    height = (png_uint_32) ul_height;
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    get_token (pnm_file, maxval_token, sizeof (maxval_token));
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    sscanf (maxval_token, "%lu", &ul_maxval);
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    maxval = (png_uint_32) ul_maxval;
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    if (maxval <= 1)
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      bit_depth = 1;
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    else if (maxval <= 3)
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      bit_depth = 2;
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    else if (maxval <= 15)
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      bit_depth = 4;
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    else if (maxval <= 255)
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      bit_depth = 8;
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    else if (maxval <= 65535U)
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      bit_depth = 16;
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    else /* maxval > 65535U */
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      return FALSE;
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  }
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  else if ((type_token[1] == '3') || (type_token[1] == '6'))
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  {
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    raw = (type_token[1] == '6');
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    color_type = PNG_COLOR_TYPE_RGB;
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    get_token (pnm_file, width_token, sizeof (width_token));
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    sscanf (width_token, "%lu", &ul_width);
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    width = (png_uint_32) ul_width;
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    get_token (pnm_file, height_token, sizeof (height_token));
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    sscanf (height_token, "%lu", &ul_height);
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    height = (png_uint_32) ul_height;
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    get_token (pnm_file, maxval_token, sizeof (maxval_token));
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    sscanf (maxval_token, "%lu", &ul_maxval);
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    maxval = (png_uint_32) ul_maxval;
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    if (maxval <= 1)
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      bit_depth = 1;
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    else if (maxval <= 3)
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      bit_depth = 2;
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    else if (maxval <= 15)
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      bit_depth = 4;
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    else if (maxval <= 255)
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      bit_depth = 8;
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    else if (maxval <= 65535U)
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      bit_depth = 16;
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    else /* maxval > 65535U */
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      return FALSE;
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  }
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  else
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  {
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    return FALSE;
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  }
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  /* read header of PGM file with alpha channel */
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  if (alpha)
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  {
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    if (color_type == PNG_COLOR_TYPE_GRAY)
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      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
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    if (color_type == PNG_COLOR_TYPE_RGB)
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      color_type = PNG_COLOR_TYPE_RGB_ALPHA;
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    get_token (alpha_file, type_token, sizeof (type_token));
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    if (type_token[0] != 'P')
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    {
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      return FALSE;
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    }
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    else if ((type_token[1] == '2') || (type_token[1] == '5'))
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    {
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      alpha_raw = (type_token[1] == '5');
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      get_token (alpha_file, width_token, sizeof (width_token));
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      sscanf (width_token, "%lu", &ul_alpha_width);
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      alpha_width = (png_uint_32) ul_alpha_width;
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      if (alpha_width != width)
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        return FALSE;
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      get_token (alpha_file, height_token, sizeof (height_token));
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      sscanf (height_token, "%lu", &ul_alpha_height);
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      alpha_height = (png_uint_32) ul_alpha_height;
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      if (alpha_height != height)
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        return FALSE;
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      get_token (alpha_file, maxval_token, sizeof (maxval_token));
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      sscanf (maxval_token, "%lu", &ul_maxval);
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      maxval = (png_uint_32) ul_maxval;
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      if (maxval <= 1)
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        alpha_depth = 1;
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      else if (maxval <= 3)
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        alpha_depth = 2;
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      else if (maxval <= 15)
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        alpha_depth = 4;
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      else if (maxval <= 255)
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        alpha_depth = 8;
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      else if (maxval <= 65535U)
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        alpha_depth = 16;
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      else /* maxval > 65535U */
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        return FALSE;
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      if (alpha_depth != bit_depth)
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        return FALSE;
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    }
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    else
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    {
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      return FALSE;
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    }
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  } /* end if alpha */
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  /* calculate the number of channels and store alpha-presence */
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  if (color_type == PNG_COLOR_TYPE_GRAY)
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    channels = 1;
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  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
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    channels = 2;
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  else if (color_type == PNG_COLOR_TYPE_RGB)
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    channels = 3;
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  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
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    channels = 4;
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#if 0
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  else
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    channels = 0; /* cannot happen */
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#endif
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  alpha_present = (channels - 1) % 2;
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
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  if (packed_bitmap)
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  {
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    /* row data is as many bytes as can fit width x channels x bit_depth */
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    row_bytes = (width * channels * bit_depth + 7) / 8;
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  }
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  else
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#endif
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  {
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    /* row_bytes is the width x number of channels x (bit-depth / 8) */
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    row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
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  }
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  if ((row_bytes == 0) ||
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      ((size_t) height > (size_t) (-1) / (size_t) row_bytes))
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  {
 | 
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    /* too big */
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    return FALSE;
 | 
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  }
 | 
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  if ((png_pixels = (png_byte *)
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       malloc ((size_t) row_bytes * (size_t) height)) == NULL)
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  {
 | 
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    /* out of memory */
 | 
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    return FALSE;
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  }
 | 
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 | 
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  /* read data from PNM file */
 | 
						|
  pix_ptr = png_pixels;
 | 
						|
 | 
						|
  for (row = 0; row < (int) height; row++)
 | 
						|
  {
 | 
						|
#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
 | 
						|
    if (packed_bitmap)
 | 
						|
    {
 | 
						|
      for (i = 0; i < (int) row_bytes; i++)
 | 
						|
      {
 | 
						|
        /* png supports this format natively so no conversion is needed */
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        *pix_ptr++ = get_data (pnm_file, 8);
 | 
						|
      }
 | 
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    }
 | 
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    else
 | 
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#endif
 | 
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    {
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      for (col = 0; col < (int) width; col++)
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      {
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        for (i = 0; i < (channels - alpha_present); i++)
 | 
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        {
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          if (raw)
 | 
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          {
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            *pix_ptr++ = get_data (pnm_file, bit_depth);
 | 
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          }
 | 
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          else
 | 
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          {
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						|
            if (bit_depth <= 8)
 | 
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            {
 | 
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              *pix_ptr++ = get_value (pnm_file, bit_depth);
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            }
 | 
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            else
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            {
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              tmp16 = get_value (pnm_file, bit_depth);
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              *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
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						|
              pix_ptr++;
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              *pix_ptr = (png_byte) (tmp16 & 0xFF);
 | 
						|
              pix_ptr++;
 | 
						|
            }
 | 
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          }
 | 
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        }
 | 
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 | 
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        if (alpha) /* read alpha-channel from pgm file */
 | 
						|
        {
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						|
          if (alpha_raw)
 | 
						|
          {
 | 
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            *pix_ptr++ = get_data (alpha_file, alpha_depth);
 | 
						|
          }
 | 
						|
          else
 | 
						|
          {
 | 
						|
            if (alpha_depth <= 8)
 | 
						|
            {
 | 
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              *pix_ptr++ = get_value (alpha_file, bit_depth);
 | 
						|
            }
 | 
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            else
 | 
						|
            {
 | 
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              tmp16 = get_value (alpha_file, bit_depth);
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              *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
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              *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
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            }
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          }
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						|
        } /* end if alpha */
 | 
						|
      } /* end if packed_bitmap */
 | 
						|
    } /* end for col */
 | 
						|
  } /* end for row */
 | 
						|
 | 
						|
  /* prepare the standard PNG structures */
 | 
						|
  png_ptr = png_create_write_struct (png_get_libpng_ver(NULL),
 | 
						|
                                     NULL, NULL, NULL);
 | 
						|
  if (!png_ptr)
 | 
						|
  {
 | 
						|
    free (png_pixels);
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
  info_ptr = png_create_info_struct (png_ptr);
 | 
						|
  if (!info_ptr)
 | 
						|
  {
 | 
						|
    png_destroy_write_struct (&png_ptr, NULL);
 | 
						|
    free (png_pixels);
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
 | 
						|
#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
 | 
						|
  if (packed_bitmap == TRUE)
 | 
						|
  {
 | 
						|
    png_set_packing (png_ptr);
 | 
						|
    png_set_invert_mono (png_ptr);
 | 
						|
  }
 | 
						|
#endif
 | 
						|
 | 
						|
  if (setjmp (png_jmpbuf (png_ptr)))
 | 
						|
  {
 | 
						|
    png_destroy_write_struct (&png_ptr, &info_ptr);
 | 
						|
    free (png_pixels);
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
 | 
						|
  /* initialize the png structure */
 | 
						|
  png_init_io (png_ptr, png_file);
 | 
						|
 | 
						|
  /* we're going to write more or less the same PNG as the input file */
 | 
						|
  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
 | 
						|
                (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
 | 
						|
                PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 | 
						|
 | 
						|
  /* write the file header information */
 | 
						|
  png_write_info (png_ptr, info_ptr);
 | 
						|
 | 
						|
  /* if needed we will allocate memory for an new array of row-pointers */
 | 
						|
  if (row_pointers == NULL)
 | 
						|
  {
 | 
						|
    if ((row_pointers = (png_byte **)
 | 
						|
         malloc (height * sizeof (png_byte *))) == NULL)
 | 
						|
    {
 | 
						|
      png_destroy_write_struct (&png_ptr, &info_ptr);
 | 
						|
      free (png_pixels);
 | 
						|
      return FALSE;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  /* set the individual row_pointers to point at the correct offsets */
 | 
						|
  for (i = 0; i < (int) height; i++)
 | 
						|
    row_pointers[i] = png_pixels + i * row_bytes;
 | 
						|
 | 
						|
  /* write out the entire image data in one call */
 | 
						|
  png_write_image (png_ptr, row_pointers);
 | 
						|
 | 
						|
  /* write the additional chunks to the PNG file (not really needed) */
 | 
						|
  png_write_end (png_ptr, info_ptr);
 | 
						|
 | 
						|
  /* clean up after the write, and free any memory allocated */
 | 
						|
  png_destroy_write_struct (&png_ptr, &info_ptr);
 | 
						|
 | 
						|
  if (row_pointers != NULL)
 | 
						|
    free (row_pointers);
 | 
						|
  if (png_pixels != NULL)
 | 
						|
    free (png_pixels);
 | 
						|
 | 
						|
  return TRUE;
 | 
						|
} /* end of pnm2png */
 | 
						|
 | 
						|
/*
 | 
						|
 * get_token - gets the first string after whitespace
 | 
						|
 */
 | 
						|
 | 
						|
void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size)
 | 
						|
{
 | 
						|
  size_t i = 0;
 | 
						|
  int ret;
 | 
						|
 | 
						|
  /* remove white-space and comment lines */
 | 
						|
  do
 | 
						|
  {
 | 
						|
    ret = fgetc (pnm_file);
 | 
						|
    if (ret == '#')
 | 
						|
    {
 | 
						|
      /* the rest of this line is a comment */
 | 
						|
      do
 | 
						|
      {
 | 
						|
        ret = fgetc (pnm_file);
 | 
						|
      }
 | 
						|
      while ((ret != '\n') && (ret != '\r') && (ret != EOF));
 | 
						|
    }
 | 
						|
    if (ret == EOF) break;
 | 
						|
    token_buf[i] = (char) ret;
 | 
						|
  }
 | 
						|
  while ((ret == '\n') || (ret == '\r') || (ret == ' '));
 | 
						|
 | 
						|
  /* read string */
 | 
						|
  do
 | 
						|
  {
 | 
						|
    ret = fgetc (pnm_file);
 | 
						|
    if (ret == EOF) break;
 | 
						|
    if (++i == token_buf_size - 1) break;
 | 
						|
    token_buf[i] = (char) ret;
 | 
						|
  }
 | 
						|
  while ((ret != '\n') && (ret != '\r') && (ret != ' '));
 | 
						|
 | 
						|
  token_buf[i] = '\0';
 | 
						|
 | 
						|
  return;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  get_data - takes first byte and converts into next pixel value,
 | 
						|
 *             taking as much bits as defined by bit-depth and
 | 
						|
 *             using the bit-depth to fill up a byte (0Ah -> AAh)
 | 
						|
 */
 | 
						|
 | 
						|
png_uint_32 get_data (FILE *pnm_file, int depth)
 | 
						|
{
 | 
						|
  static int bits_left = 0;
 | 
						|
  static int old_value = 0;
 | 
						|
  static int mask = 0;
 | 
						|
  int i;
 | 
						|
  png_uint_32 ret_value;
 | 
						|
 | 
						|
  if (mask == 0)
 | 
						|
    for (i = 0; i < depth; i++)
 | 
						|
      mask = (mask >> 1) | 0x80;
 | 
						|
 | 
						|
  if (bits_left <= 0)
 | 
						|
  {
 | 
						|
    old_value = fgetc (pnm_file);
 | 
						|
    bits_left = 8;
 | 
						|
  }
 | 
						|
 | 
						|
  ret_value = old_value & mask;
 | 
						|
  for (i = 1; i < (8 / depth); i++)
 | 
						|
    ret_value = ret_value || (ret_value >> depth);
 | 
						|
 | 
						|
  old_value = (old_value << depth) & 0xFF;
 | 
						|
  bits_left -= depth;
 | 
						|
 | 
						|
  return ret_value;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  get_value - takes first (numeric) string and converts into number,
 | 
						|
 *              using the bit-depth to fill up a byte (0Ah -> AAh)
 | 
						|
 */
 | 
						|
 | 
						|
png_uint_32 get_value (FILE *pnm_file, int depth)
 | 
						|
{
 | 
						|
  static png_uint_32 mask = 0;
 | 
						|
  char token[16];
 | 
						|
  unsigned long ul_ret_value;
 | 
						|
  png_uint_32 ret_value;
 | 
						|
  int i = 0;
 | 
						|
 | 
						|
  if (mask == 0)
 | 
						|
    for (i = 0; i < depth; i++)
 | 
						|
      mask = (mask << 1) | 0x01;
 | 
						|
 | 
						|
  get_token (pnm_file, token, sizeof (token));
 | 
						|
  sscanf (token, "%lu", &ul_ret_value);
 | 
						|
  ret_value = (png_uint_32) ul_ret_value;
 | 
						|
 | 
						|
  ret_value &= mask;
 | 
						|
 | 
						|
  if (depth < 8)
 | 
						|
    for (i = 0; i < (8 / depth); i++)
 | 
						|
      ret_value = (ret_value << depth) || ret_value;
 | 
						|
 | 
						|
  return ret_value;
 | 
						|
}
 | 
						|
 | 
						|
/* end of source */
 |