Exemple #1
0
Fichier : wpng.c Projet : phuc/wpng
void convert2png(unsigned char ** buffer, FILE *outfile) {
  ulg rowbytes;
  int rc;
  
  int nx = 800;
  int ny = 600;
  
  wpng_info.infile = NULL;
  wpng_info.outfile = NULL;
  wpng_info.image_data = NULL;
  wpng_info.row_pointers = NULL;
  wpng_info.filter = FALSE;
  wpng_info.interlaced = FALSE;
  wpng_info.have_bg = FALSE;
  wpng_info.have_time = FALSE;
  wpng_info.have_text = 0;
  wpng_info.gamma = 0.0;

  // input
  wpng_info.outfile = outfile;
  wpng_info.filter = TRUE;
  wpng_info.width = nx;
  wpng_info.height = ny;
  wpng_info.pnmtype = 6;
  wpng_info.have_bg = FALSE;
  wpng_info.sample_depth = 8; 
  wpng_info.have_text = FALSE;
  
  /* prepare the text buffers for libpng's use; note that even though
   * PNG's png_text struct includes a length field, we don't have to fill
   * it out */

  rc = writepng_init(&wpng_info);
  
  // wpng_info.pnmtype == 6
  rowbytes = wpng_info.width * 3;

  /* read and write the image, either in its entirety (if writing interlaced
   * PNG) or row by row (if non-interlaced) */

  fprintf(stderr, "Encoding image data...\n");
  fflush(stderr);
  
  long j;
  wpng_info.infile = fopen("aU.ppm","rb");
  wpng_info.image_data = (unsigned char *)malloc(rowbytes);
    
  for (j = 0;  j < wpng_info.height;  j++) {
    memcpy(wpng_info.image_data, buffer[j], rowbytes);    
    writepng_encode_row(&wpng_info);
  }
  
  writepng_encode_finish(&wpng_info);
  fprintf(stderr, "Done.\n");
  fflush(stderr);
  writepng_cleanup(&wpng_info);
  wpng_cleanup();
}
Exemple #2
0
int main ( int argc, char **argv ) {
#ifndef DOS_OS2_W32
    FILE *keybd;
#endif
#ifdef sgi
    FILE *tmpfile;      /* or we could just use keybd, since no overlap */
    char tmpline[80];
#endif
    char *inname = NULL, outname[256];
    char *p, pnmchar, pnmline[256];
    char *bgstr, *textbuf = NULL;
    ulg rowbytes;
    int rc, len = 0;
    int error = 0;
    int text = FALSE;
    int maxval;
    double LUT_exponent;                /* just the lookup table */
    double CRT_exponent = 2.2;          /* just the monitor */
    double default_display_exponent;    /* whole display system */
    double default_gamma = 0.0;


    wpng_info.infile = NULL;
    wpng_info.outfile = NULL;
    wpng_info.image_data = NULL;
    wpng_info.row_pointers = NULL;
    wpng_info.filter = FALSE;
    wpng_info.interlaced = FALSE;
    wpng_info.have_bg = FALSE;
    wpng_info.have_time = FALSE;
    wpng_info.have_text = 0;
    wpng_info.gamma = 0.0;


    /* First get the default value for our display-system exponent, i.e.,
     * the product of the CRT exponent and the exponent corresponding to
     * the frame-buffer's lookup table (LUT), if any.  If the PNM image
     * looks correct on the user's display system, its file gamma is the
     * inverse of this value.  (Note that this is not an exhaustive list
     * of LUT values--e.g., OpenStep has a lot of weird ones--but it should
     * cover 99% of the current possibilities.  This section must ensure
     * that default_display_exponent is positive.) */

#if defined(NeXT)
    /* third-party utilities can modify the default LUT exponent */
    LUT_exponent = 1.0 / 2.2;
    /*
    if (some_next_function_that_returns_gamma(&next_gamma))
        LUT_exponent = 1.0 / next_gamma;
     */
#elif defined(sgi)
    LUT_exponent = 1.0 / 1.7;
    /* there doesn't seem to be any documented function to
     * get the "gamma" value, so we do it the hard way */
    tmpfile = fopen ( "/etc/config/system.glGammaVal", "r" );
    if ( tmpfile ) {
        double sgi_gamma;

        fgets ( tmpline, 80, tmpfile );
        fclose ( tmpfile );
        sgi_gamma = atof ( tmpline );
        if ( sgi_gamma > 0.0 )
            LUT_exponent = 1.0 / sgi_gamma;
    }
#elif defined(Macintosh)
    LUT_exponent = 1.8 / 2.61;
    /*
    if (some_mac_function_that_returns_gamma(&mac_gamma))
        LUT_exponent = mac_gamma / 2.61;
     */
#else
    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
#endif

    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
    default_display_exponent = LUT_exponent * CRT_exponent;


    /* If the user has set the SCREEN_GAMMA environment variable as suggested
     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
     * use the default value we just calculated.  Either way, the user may
     * override this via a command-line option. */

    if ( ( p = getenv ( "SCREEN_GAMMA" ) ) != NULL ) {
        double exponent = atof ( p );

        if ( exponent > 0.0 )
            default_gamma = 1.0 / exponent;
    }

    if ( default_gamma == 0.0 )
        default_gamma = 1.0 / default_display_exponent;


    /* Now parse the command line for options and the PNM filename. */

    while ( *++argv && !error ) {
        if ( !strncmp ( *argv, "-i", 2 ) ) {
            wpng_info.interlaced = TRUE;
        } else if ( !strncmp ( *argv, "-time", 3 ) ) {
            wpng_info.modtime = time ( NULL );
            wpng_info.have_time = TRUE;
        } else if ( !strncmp ( *argv, "-text", 3 ) ) {
            text = TRUE;
        } else if ( !strncmp ( *argv, "-gamma", 2 ) ) {
            if ( !*++argv )
                ++error;
            else {
                wpng_info.gamma = atof ( *argv );
                if ( wpng_info.gamma <= 0.0 )
                    ++error;
                else if ( wpng_info.gamma > 1.01 )
                    fprintf ( stderr, PROGNAME
                              " warning:  file gammas are usually less than 1.0\n" );
            }
        } else if ( !strncmp ( *argv, "-bgcolor", 4 ) ) {
            if ( !*++argv )
                ++error;
            else {
                bgstr = *argv;
                if ( strlen ( bgstr ) != 7 || bgstr[0] != '#' )
                    ++error;
                else {
                    unsigned r, g, b;  /* this way quiets compiler warnings */

                    sscanf ( bgstr+1, "%2x%2x%2x", &r, &g, &b );
                    wpng_info.bg_red   = ( uch ) r;
                    wpng_info.bg_green = ( uch ) g;
                    wpng_info.bg_blue  = ( uch ) b;
                    wpng_info.have_bg = TRUE;
                }
            }
        } else {
            if ( **argv != '-' ) {
                inname = *argv;
                if ( argv[1] ) /* shouldn't be any more args after filename */
                    ++error;
            } else
                ++error;   /* not expecting any other options */
        }
    }


    /* open the input and output files, or register an error and abort */

    if ( !inname ) {
        if ( isatty ( 0 ) ) {
            fprintf ( stderr, PROGNAME
                      ":  must give input filename or provide image data via stdin\n" );
            ++error;
        } else {
#ifdef DOS_OS2_W32
            /* some buggy C libraries require BOTH setmode() and fdopen(bin) */
            setmode ( fileno ( stdin ), O_BINARY );
            setmode ( fileno ( stdout ), O_BINARY );
#endif
            if ( ( wpng_info.infile = fdopen ( fileno ( stdin ), "rb" ) ) == NULL ) {
                fprintf ( stderr, PROGNAME
                          ":  unable to reopen stdin in binary mode\n" );
                ++error;
            } else if ( ( wpng_info.outfile = fdopen ( fileno ( stdout ), "wb" ) ) == NULL ) {
                fprintf ( stderr, PROGNAME
                          ":  unable to reopen stdout in binary mode\n" );
                fclose ( wpng_info.infile );
                ++error;
            } else
                wpng_info.filter = TRUE;
        }
    } else if ( ( len = strlen ( inname ) ) > 250 ) {
        fprintf ( stderr, PROGNAME ":  input filename is too long [%d chars]\n",
                  len );
        ++error;
    } else if ( ! ( wpng_info.infile = fopen ( inname, "rb" ) ) ) {
        fprintf ( stderr, PROGNAME ":  can't open input file [%s]\n", inname );
        ++error;
    }

    if ( !error ) {
        fgets ( pnmline, 256, wpng_info.infile );
        if ( pnmline[0] != 'P' || ( ( pnmchar = pnmline[1] ) != '5' &&
                                    pnmchar != '6' && pnmchar != '8' ) ) {
            fprintf ( stderr, PROGNAME
                      ":  input file [%s] is not a binary PGM, PPM or PAM file\n",
                      inname );
            ++error;
        } else {
            wpng_info.pnmtype = ( int ) ( pnmchar - '0' );
            if ( wpng_info.pnmtype != 8 )
                wpng_info.have_bg = FALSE;  /* no need for bg if opaque */
            do {
                fgets ( pnmline, 256, wpng_info.infile ); /* lose any comments */
            } while ( pnmline[0] == '#' );
            sscanf ( pnmline, "%ld %ld", &wpng_info.width, &wpng_info.height );
            do {
                fgets ( pnmline, 256, wpng_info.infile ); /* more comment lines */
            } while ( pnmline[0] == '#' );
            sscanf ( pnmline, "%d", &maxval );
            if ( wpng_info.width <= 0L || wpng_info.height <= 0L ||
                    maxval != 255 ) {
                fprintf ( stderr, PROGNAME
                          ":  only positive width/height, maxval == 255 allowed \n" );
                ++error;
            }
            wpng_info.sample_depth = 8;  /* <==> maxval 255 */

            if ( !wpng_info.filter ) {
                /* make outname from inname */
                if ( ( p = strrchr ( inname, '.' ) ) == NULL ||
                        ( p - inname ) != ( len - 4 ) ) {
                    strcpy ( outname, inname );
                    strcpy ( outname+len, ".png" );
                } else {
                    len -= 4;
                    strncpy ( outname, inname, len );
                    strcpy ( outname+len, ".png" );
                }
                /* check if outname already exists; if not, open */
                if ( ( wpng_info.outfile = fopen ( outname, "rb" ) ) != NULL ) {
                    fprintf ( stderr, PROGNAME ":  output file exists [%s]\n",
                              outname );
                    fclose ( wpng_info.outfile );
                    ++error;
                } else if ( ! ( wpng_info.outfile = fopen ( outname, "wb" ) ) ) {
                    fprintf ( stderr, PROGNAME ":  can't open output file [%s]\n",
                              outname );
                    ++error;
                }
            }
        }
        if ( error ) {
            fclose ( wpng_info.infile );
            wpng_info.infile = NULL;
            if ( wpng_info.filter ) {
                fclose ( wpng_info.outfile );
                wpng_info.outfile = NULL;
            }
        }
    }


    /* if we had any errors, print usage and die horrible death...arrr! */

    if ( error ) {
        fprintf ( stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, APPNAME );
        writepng_version_info();
        fprintf ( stderr, "\n"
                  "Usage:  %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] pnmfile\n"
                  "or: ... | %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] | ...\n"
                  "    exp \ttransfer-function exponent (``gamma'') of the image in\n"
                  "\t\t  floating-point format (e.g., ``%.5f''); if image looks\n"
                  "\t\t  correct on given display system, image gamma is equal to\n"
                  "\t\t  inverse of display-system exponent, i.e., 1 / (LUT * CRT)\n"
                  "\t\t  (where LUT = lookup-table exponent and CRT = CRT exponent;\n"
                  "\t\t  first varies, second is usually 2.2, all are positive)\n"
                  "    bg  \tdesired background color for alpha-channel images, in\n"
                  "\t\t  7-character hex RGB format (e.g., ``#ff7700'' for orange:\n"
                  "\t\t  same as HTML colors)\n"
                  "    -text\tprompt interactively for text info (tEXt chunks)\n"
                  "    -time\tinclude a tIME chunk (last modification time)\n"
                  "    -interlace\twrite interlaced PNG image\n"
                  "\n"
                  "pnmfile or stdin must be a binary PGM (`P5'), PPM (`P6') or (extremely\n"
                  "unofficial and unsupported!) PAM (`P8') file.  Currently it is required\n"
                  "to have maxval == 255 (i.e., no scaling).  If pnmfile is specified, it\n"
                  "is converted to the corresponding PNG file with the same base name but a\n"
                  "``.png'' extension; files read from stdin are converted and sent to stdout.\n"
                  "The conversion is progressive (low memory usage) unless interlacing is\n"
                  "requested; in that case the whole image will be buffered in memory and\n"
                  "written in one call.\n"
                  "\n", PROGNAME, PROGNAME, default_gamma );
        exit ( 1 );
    }


    /* prepare the text buffers for libpng's use; note that even though
     * PNG's png_text struct includes a length field, we don't have to fill
     * it out */

    if ( text &&
#ifndef DOS_OS2_W32
            ( keybd = fdopen ( fileno ( stderr ), "r" ) ) != NULL &&
#endif
            ( textbuf = ( char * ) malloc ( ( 5 + 9 ) *75 ) ) != NULL ) {
        int i, valid, result;

        fprintf ( stderr,
                  "Enter text info (no more than 72 characters per line);\n" );
        fprintf ( stderr, "to skip a field, hit the <Enter> key.\n" );
        /* note:  just <Enter> leaves len == 1 */

        do {
            valid = TRUE;
            p = textbuf + TEXT_TITLE_OFFSET;
            fprintf ( stderr, "  Title: " );
            fflush ( stderr );
            if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 ) {
                if ( p[len-1] == '\n' )
                    p[--len] = '\0';
                wpng_info.title = p;
                wpng_info.have_text |= TEXT_TITLE;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_TITLE;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_TITLE;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

        do {
            valid = TRUE;
            p = textbuf + TEXT_AUTHOR_OFFSET;
            fprintf ( stderr, "  Author: " );
            fflush ( stderr );
            if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 ) {
                if ( p[len-1] == '\n' )
                    p[--len] = '\0';
                wpng_info.author = p;
                wpng_info.have_text |= TEXT_AUTHOR;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_AUTHOR;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_AUTHOR;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

        do {
            valid = TRUE;
            p = textbuf + TEXT_DESC_OFFSET;
            fprintf ( stderr, "  Description (up to 9 lines):\n" );
            for ( i = 1;  i < 10;  ++i ) {
                fprintf ( stderr, "    [%d] ", i );
                fflush ( stderr );
                if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 )
                    p += len;   /* now points at NULL; char before is newline */
                else
                    break;
            }
            if ( ( len = p - ( textbuf + TEXT_DESC_OFFSET ) ) > 1 ) {
                if ( p[-1] == '\n' ) {
                    p[-1] = '\0';
                    --len;
                }
                wpng_info.desc = textbuf + TEXT_DESC_OFFSET;
                wpng_info.have_text |= TEXT_DESC;
                p = textbuf + TEXT_DESC_OFFSET;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_DESC;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_DESC;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

        do {
            valid = TRUE;
            p = textbuf + TEXT_COPY_OFFSET;
            fprintf ( stderr, "  Copyright: " );
            fflush ( stderr );
            if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 ) {
                if ( p[len-1] == '\n' )
                    p[--len] = '\0';
                wpng_info.copyright = p;
                wpng_info.have_text |= TEXT_COPY;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_COPY;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_COPY;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

        do {
            valid = TRUE;
            p = textbuf + TEXT_EMAIL_OFFSET;
            fprintf ( stderr, "  E-mail: " );
            fflush ( stderr );
            if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 ) {
                if ( p[len-1] == '\n' )
                    p[--len] = '\0';
                wpng_info.email = p;
                wpng_info.have_text |= TEXT_EMAIL;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_EMAIL;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_EMAIL;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

        do {
            valid = TRUE;
            p = textbuf + TEXT_URL_OFFSET;
            fprintf ( stderr, "  URL: " );
            fflush ( stderr );
            if ( FGETS ( p, 74, keybd ) && ( len = strlen ( p ) ) > 1 ) {
                if ( p[len-1] == '\n' )
                    p[--len] = '\0';
                wpng_info.url = p;
                wpng_info.have_text |= TEXT_URL;
                if ( ( result = wpng_isvalid_latin1 ( ( uch * ) p, len ) ) >= 0 ) {
                    fprintf ( stderr, "    " PROGNAME " warning:  character code"
                              " %u is %sdiscouraged by the PNG\n    specification "
                              "[first occurrence was at character position #%d]\n",
                              ( unsigned ) p[result], ( p[result] == 27 ) ? "strongly " : "",
                              result+1 );
                    fflush ( stderr );
#ifdef FORBID_LATIN1_CTRL
                    wpng_info.have_text &= ~TEXT_URL;
                    valid = FALSE;
#else
                    if ( p[result] == 27 ) {  /* escape character */
                        wpng_info.have_text &= ~TEXT_URL;
                        valid = FALSE;
                    }
#endif
                }
            }
        } while ( !valid );

#ifndef DOS_OS2_W32
        fclose ( keybd );
#endif

    } else if ( text ) {
        fprintf ( stderr, PROGNAME ":  unable to allocate memory for text\n" );
        text = FALSE;
        wpng_info.have_text = 0;
    }


    /* allocate libpng stuff, initialize transformations, write pre-IDAT data */

    if ( ( rc = writepng_init ( &wpng_info ) ) != 0 ) {
        switch ( rc ) {
        case 2:
            fprintf ( stderr, PROGNAME
                      ":  libpng initialization problem (longjmp)\n" );
            break;
        case 4:
            fprintf ( stderr, PROGNAME ":  insufficient memory\n" );
            break;
        case 11:
            fprintf ( stderr, PROGNAME
                      ":  internal logic error (unexpected PNM type)\n" );
            break;
        default:
            fprintf ( stderr, PROGNAME
                      ":  unknown writepng_init() error\n" );
            break;
        }
        exit ( rc );
    }


    /* free textbuf, since it's a completely local variable and all text info
     * has just been written to the PNG file */

    if ( text && textbuf ) {
        free ( textbuf );
        textbuf = NULL;
    }


    /* calculate rowbytes on basis of image type; note that this becomes much
     * more complicated if we choose to support PBM type, ASCII PNM types, or
     * 16-bit-per-sample binary data [currently not an official NetPBM type] */

    if ( wpng_info.pnmtype == 5 )
        rowbytes = wpng_info.width;
    else if ( wpng_info.pnmtype == 6 )
        rowbytes = wpng_info.width * 3;
    else /* if (wpng_info.pnmtype == 8) */
        rowbytes = wpng_info.width * 4;


    /* read and write the image, either in its entirety (if writing interlaced
     * PNG) or row by row (if non-interlaced) */

    fprintf ( stderr, "Encoding image data...\n" );
    fflush ( stderr );

    if ( wpng_info.interlaced ) {
        long i;
        ulg bytes;
        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */

        wpng_info.image_data = ( uch * ) malloc ( image_bytes );
        wpng_info.row_pointers = ( uch ** ) malloc ( wpng_info.height*sizeof ( uch * ) );
        if ( wpng_info.image_data == NULL || wpng_info.row_pointers == NULL ) {
            fprintf ( stderr, PROGNAME ":  insufficient memory for image data\n" );
            writepng_cleanup ( &wpng_info );
            wpng_cleanup();
            exit ( 5 );
        }
        for ( i = 0;  i < wpng_info.height;  ++i )
            wpng_info.row_pointers[i] = wpng_info.image_data + i*rowbytes;
        bytes = fread ( wpng_info.image_data, 1, image_bytes, wpng_info.infile );
        if ( bytes != image_bytes ) {
            fprintf ( stderr, PROGNAME ":  expected %lu bytes, got %lu bytes\n",
                      image_bytes, bytes );
            fprintf ( stderr, "  (continuing anyway)\n" );
        }
        if ( writepng_encode_image ( &wpng_info ) != 0 ) {
            fprintf ( stderr, PROGNAME
                      ":  libpng problem (longjmp) while writing image data\n" );
            writepng_cleanup ( &wpng_info );
            wpng_cleanup();
            exit ( 2 );
        }

    } else { /* not interlaced:  write progressively (row by row) */
        long j;
        ulg bytes;

        wpng_info.image_data = ( uch * ) malloc ( rowbytes );
        if ( wpng_info.image_data == NULL ) {
            fprintf ( stderr, PROGNAME ":  insufficient memory for row data\n" );
            writepng_cleanup ( &wpng_info );
            wpng_cleanup();
            exit ( 5 );
        }
        error = 0;
        for ( j = wpng_info.height;  j > 0L;  --j ) {
            bytes = fread ( wpng_info.image_data, 1, rowbytes, wpng_info.infile );
            if ( bytes != rowbytes ) {
                fprintf ( stderr, PROGNAME
                          ":  expected %lu bytes, got %lu bytes (row %ld)\n", rowbytes,
                          bytes, wpng_info.height-j );
                ++error;
                break;
            }
            if ( writepng_encode_row ( &wpng_info ) != 0 ) {
                fprintf ( stderr, PROGNAME
                          ":  libpng problem (longjmp) while writing row %ld\n",
                          wpng_info.height-j );
                ++error;
                break;
            }
        }
        if ( error ) {
            writepng_cleanup ( &wpng_info );
            wpng_cleanup();
            exit ( 2 );
        }
        if ( writepng_encode_finish ( &wpng_info ) != 0 ) {
            fprintf ( stderr, PROGNAME ":  error on final libpng call\n" );
            writepng_cleanup ( &wpng_info );
            wpng_cleanup();
            exit ( 2 );
        }
    }


    /* OK, we're done (successfully):  clean up all resources and quit */

    fprintf ( stderr, "Done.\n" );
    fflush ( stderr );

    writepng_cleanup ( &wpng_info );
    wpng_cleanup();

    return 0;
}
Exemple #3
0
Fichier : wpng.c Projet : phuc/wpng
void write_ppm2png(FILE *infile, FILE *outfile) {
    char pnmline[256];
    ulg rowbytes;
    int rc;

    wpng_info.infile = NULL;
    wpng_info.outfile = NULL;
    wpng_info.image_data = NULL;
    wpng_info.row_pointers = NULL;
    wpng_info.filter = FALSE;
    wpng_info.interlaced = FALSE;
    wpng_info.have_bg = FALSE;
    wpng_info.have_time = FALSE;
    wpng_info.have_text = 0;
    wpng_info.gamma = 0.0;

    // input
    wpng_info.infile = infile;
    wpng_info.outfile = outfile;
    wpng_info.filter = TRUE;
    wpng_info.width = 800;
    wpng_info.height = 600;
    wpng_info.pnmtype = 6;
    wpng_info.have_bg = FALSE;
    wpng_info.sample_depth = 8; 
    wpng_info.have_text = FALSE;
    
    fgets(pnmline, 256, wpng_info.infile);
    do {
        fgets(pnmline, 256, wpng_info.infile);  /* lose any comments */
    } while (pnmline[0] == '#');
    do {
        fgets(pnmline, 256, wpng_info.infile);  /* more comment lines */
    } while (pnmline[0] == '#');    

    /* prepare the text buffers for libpng's use; note that even though
     * PNG's png_text struct includes a length field, we don't have to fill
     * it out */
  
    rc = writepng_init(&wpng_info);
    
    // wpng_info.pnmtype == 6
    rowbytes = wpng_info.width * 3;

    /* read and write the image, either in its entirety (if writing interlaced
     * PNG) or row by row (if non-interlaced) */

    fprintf(stderr, "Encoding image data...\n");
    fflush(stderr);
    
    long j;

    wpng_info.image_data = (uch *)malloc(rowbytes);
    for (j = wpng_info.height;  j > 0L;  --j) {
        fread(wpng_info.image_data, 1, rowbytes, wpng_info.infile);        
        writepng_encode_row(&wpng_info);
    }
    writepng_encode_finish(&wpng_info);
    fprintf(stderr, "Done.\n");
    fflush(stderr);
    writepng_cleanup(&wpng_info);
    wpng_cleanup();
}