/* *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com> * *  version 1.0 - 1999.10.15 - First version. * *  Permission to use, copy, modify, and distribute this software and *  its documentation for any purpose and without fee is hereby granted, *  provided that the above copyright notice appear in all copies and *  that both that copyright notice and this permission notice appear in *  supporting documentation. This software is provided "as is" without *  express or implied warranty. */#include <stdio.h>#include <stdlib.h>#ifdef __TURBOC__#include <mem.h>#include <fcntl.h>#endif#ifndef BOOL#define BOOL unsigned char#endif#ifndef TRUE#define TRUE (BOOL) 1#endif#ifndef FALSE#define FALSE (BOOL) 0#endif#define STDIN  0#define STDOUT 1#define STDERR 2/* to make pnm2png verbose so we can find problems (needs to be before png.h) */#ifndef PNG_DEBUG#define PNG_DEBUG 0#endif#include "png.h"/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */#ifndef png_jmpbuf#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)#endif/* function prototypes */int  main (int argc, char *argv[]);void usage ();BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);void get_token(FILE *pnm_file, char *token);png_uint_32 get_data (FILE *pnm_file, int depth);png_uint_32 get_value (FILE *pnm_file, int depth);/* *  main */int main(int argc, char *argv[]){  FILE *fp_rd = stdin;  FILE *fp_al = NULL;  FILE *fp_wr = stdout;  BOOL interlace = FALSE;  BOOL alpha = FALSE;  int argi;  for (argi = 1; argi < argc; argi++)  {    if (argv[argi][0] == '-')    {      switch (argv[argi][1])      {        case 'i':          interlace = TRUE;          break;        case 'a':          alpha = TRUE;          argi++;          if ((fp_al = fopen (argv[argi], "rb")) == NULL)          {            fprintf (stderr, "PNM2PNG\n");            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",               argv[argi]);            exit (1);          }          break;        case 'h':        case '?':          usage();          exit(0);          break;        default:          fprintf (stderr, "PNM2PNG\n");          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);          usage();          exit(1);          break;      } /* end switch */    }    else if (fp_rd == stdin)    {      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)      {        fprintf (stderr, "PNM2PNG\n");        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);        exit (1);      }    }    else if (fp_wr == stdout)    {      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)      {        fprintf (stderr, "PNM2PNG\n");        fprintf (stderr, "Error:  can not create PNG-file %s\n", argv[argi]);        exit (1);      }    }    else    {      fprintf (stderr, "PNM2PNG\n");      fprintf (stderr, "Error:  too many parameters\n");      usage();      exit (1);    }  } /* end for */#ifdef __TURBOC__  /* set stdin/stdout to binary, we're reading the PNM always! in binary format */  if (fp_rd == stdin)  {    setmode (STDIN, O_BINARY);  }  if (fp_wr == stdout)  {    setmode (STDOUT, O_BINARY);  }#endif  /* call the conversion program itself */  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)  {    fprintf (stderr, "PNM2PNG\n");    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");    exit (1);  }  /* close input file */  fclose (fp_rd);  /* close output file */  fclose (fp_wr);  /* close alpha file */  if (alpha)    fclose (fp_al);  return 0;}/* *  usage */void usage(){  fprintf (stderr, "PNM2PNG\n");  fprintf (stderr, "   by Willem van Schaik, 1999\n");#ifdef __TURBOC__  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");#else  fprintf (stderr, "   for Linux (and Unix) compilers\n");#endif  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");  fprintf (stderr, "   or:  ... | pnm2png [options]\n");  fprintf (stderr, "Options:\n");  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");  fprintf (stderr, "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");  fprintf (stderr, "   -h | -?  print this help-information\n");}/* *  pnm2png */BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha){  png_struct    *png_ptr = NULL;  png_info      *info_ptr = NULL;  png_byte      *png_pixels = NULL;  png_byte      **row_pointers = NULL;  png_byte      *pix_ptr = NULL;  png_uint_32   row_bytes;  char          type_token[16];  char          width_token[16];  char          height_token[16];  char          maxval_token[16];  int           color_type;  png_uint_32   width, alpha_width;  png_uint_32   height, alpha_height;  png_uint_32   maxval;  int           bit_depth = 0;  int           channels;  int           alpha_depth = 0;  int           alpha_present;  int           row, col;  BOOL          raw, alpha_raw = FALSE;  png_uint_32   tmp16;  int           i;  /* read header of PNM file */  get_token(pnm_file, type_token);  if (type_token[0] != 'P')  {    return FALSE;  }  else if ((type_token[1] == '1') || (type_token[1] == '4'))  {    raw = (type_token[1] == '4');    color_type = PNG_COLOR_TYPE_GRAY;    bit_depth = 1;  }  else if ((type_token[1] == '2') || (type_token[1] == '5'))  {    raw = (type_token[1] == '5');    color_type = PNG_COLOR_TYPE_GRAY;    get_token(pnm_file, width_token);    sscanf (width_token, "%lu", &width);    get_token(pnm_file, height_token);    sscanf (height_token, "%lu", &height);    get_token(pnm_file, maxval_token);    sscanf (maxval_token, "%lu", &maxval);    if (maxval <= 1)      bit_depth = 1;    else if (maxval <= 3)      bit_depth = 2;    else if (maxval <= 15)      bit_depth = 4;    else if (maxval <= 255)      bit_depth = 8;    else /* if (maxval <= 65535) */      bit_depth = 16;  }  else if ((type_token[1] == '3') || (type_token[1] == '6'))  {    raw = (type_token[1] == '6');    color_type = PNG_COLOR_TYPE_RGB;    get_token(pnm_file, width_token);    sscanf (width_token, "%lu", &width);    get_token(pnm_file, height_token);    sscanf (height_token, "%lu", &height);    get_token(pnm_file, maxval_token);    sscanf (maxval_token, "%lu", &maxval);    if (maxval <= 1)      bit_depth = 1;    else if (maxval <= 3)      bit_depth = 2;    else if (maxval <= 15)      bit_depth = 4;    else if (maxval <= 255)      bit_depth = 8;    else /* if (maxval <= 65535) */      bit_depth = 16;  }  else  {    return FALSE;  }  /* read header of PGM file with alpha channel */  if (alpha)  {    if (color_type == PNG_COLOR_TYPE_GRAY)      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;    if (color_type == PNG_COLOR_TYPE_RGB)      color_type = PNG_COLOR_TYPE_RGB_ALPHA;    get_token(alpha_file, type_token);    if (type_token[0] != 'P')    {      return FALSE;    }    else if ((type_token[1] == '2') || (type_token[1] == '5'))    {      alpha_raw = (type_token[1] == '5');      get_token(alpha_file, width_token);      sscanf (width_token, "%lu", &alpha_width);      if (alpha_width != width)        return FALSE;      get_token(alpha_file, height_token);      sscanf (height_token, "%lu", &alpha_height);      if (alpha_height != height)        return FALSE;      get_token(alpha_file, maxval_token);      sscanf (maxval_token, "%lu", &maxval);      if (maxval <= 1)        alpha_depth = 1;      else if (maxval <= 3)        alpha_depth = 2;      else if (maxval <= 15)        alpha_depth = 4;      else if (maxval <= 255)        alpha_depth = 8;      else /* if (maxval <= 65535) */        alpha_depth = 16;      if (alpha_depth != bit_depth)        return FALSE;    }    else    {      return FALSE;    }  } /* end if alpha */  /* calculate the number of channels and store alpha-presence */  if (color_type == PNG_COLOR_TYPE_GRAY)    channels = 1;  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)    channels = 2;  else if (color_type == PNG_COLOR_TYPE_RGB)    channels = 3;  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)    channels = 4;  else    channels = 0; /* should not happen */  alpha_present = (channels - 1) % 2;  /* row_bytes is the width x number of channels x (bit-depth / 8) */  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)    return FALSE;  /* read data from PNM file */  pix_ptr = png_pixels;  for (row = 0; row < height; row++)  {    for (col = 0; col < width; col++)    {      for (i = 0; i < (channels - alpha_present); i++)      {        if (raw)          *pix_ptr++ = get_data (pnm_file, bit_depth);        else          if (bit_depth <= 8)            *pix_ptr++ = get_value (pnm_file, bit_depth);          else          {            tmp16 = get_value (pnm_file, bit_depth);            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);            pix_ptr++;            *pix_ptr = (png_byte) (tmp16 & 0xFF);            pix_ptr++;          }      }      if (alpha) /* read alpha-channel from pgm file */      {        if (alpha_raw)          *pix_ptr++ = get_data (alpha_file, alpha_depth);        else          if (alpha_depth <= 8)            *pix_ptr++ = get_value (alpha_file, bit_depth);          else          {            tmp16 = get_value (alpha_file, bit_depth);            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);          }      } /* if alpha */    } /* end for col */  } /* end for row */  /* prepare the standard PNG structures */  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);  if (!png_ptr)  {    return FALSE;  }  info_ptr = png_create_info_struct (png_ptr);  if (!info_ptr)  {    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);    return FALSE;  }  /* setjmp() must be called in every function that calls a PNG-reading libpng function */  if (setjmp (png_jmpbuf(png_ptr)))  {    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);    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 == (unsigned char**) NULL)  {    if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)    {      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);      return FALSE;    }  }  /* set the individual row_pointers to point at the correct offsets */  for (i = 0; i < (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 chuncks 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, (png_infopp) NULL);  if (row_pointers != (unsigned char**) NULL)    free (row_pointers);  if (png_pixels != (unsigned char*) 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){  int i = 0;  /* remove white-space */  do  {    token[i] = (unsigned char) fgetc (pnm_file);  }  while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));  /* read string */  do  {    i++;    token[i] = (unsigned char) fgetc (pnm_file);  }  while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));  token[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;  png_byte token[16];  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, (char *) token);  sscanf ((const char *) token, "%lu", &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 */