/* gouldtoppm.c - read GOULD imaging system files and write a portable pixmap
**
** Copyright (C) 1990  Stephen P. Lesniewski
**
** 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 "ppm.h"

#define MAXVAL 255

static void getgouldheader ARGS(( FILE *infile, unsigned long *cols, unsigned long *nlines, unsigned long *bytesperline, unsigned long *bitsperpixel, unsigned long *NB ));

int
main( argc, argv )
int argc;
char *argv[];
{
        FILE *ifp;
        pixel *pixrow;

        unsigned long cols, nlines, bytesperline, bitsperpixel, NB, x, y;
        unsigned char pbuffer[4];

        int color_type;


        ppm_init( &argc, argv );

        if ( argc > 2 )
                pm_usage( "[gouldfile]" );

        if ( argc == 2 )
                ifp = pm_openr( argv[1] );
        else
                ifp = stdin;

        getgouldheader( ifp, &cols, &nlines, &bytesperline, &bitsperpixel, &NB);

        ppm_writeppminit(stdout, cols, nlines, MAXVAL, 0);

        color_type = bitsperpixel/8;
        if (color_type == 0) color_type = NB;

        pixrow = ppm_allocrow(cols);

        for (y = 0; y < nlines; ++y)
        {
                for (x = 0; x < cols; ++x)
                {
                        switch (color_type)
                        {
                        case 0:
                                pm_error("incorrect color type" );

                        case 1:
                                fread(pbuffer, 1, 1, ifp);
                                PPM_ASSIGN( pixrow[x], pbuffer[0], pbuffer[0], pbuffer[0]);
                                break;

                        case 2:
                                fread(pbuffer, 2, 1, ifp);
                                PPM_ASSIGN( pixrow[x], pbuffer[0], pbuffer[1], pbuffer[1]);
                                break;

                        case 3:
                                fread(pbuffer, 3, 1, ifp);
                                PPM_ASSIGN( pixrow[x], pbuffer[0], pbuffer[1], pbuffer[2]);
                                break;

                        default :
                                fread(pbuffer, 3, 1, ifp);
                                PPM_ASSIGN( pixrow[x], pbuffer[0], pbuffer[1], pbuffer[2]);
                                break;

                        } /* switch */
                }
                ppm_writeppmrow(stdout, pixrow, cols, MAXVAL, 0);
        }

        pm_close(ifp);
        pm_close(stdout);

        exit(0);
}



static void
getgouldheader( infile, cols, nlines, bytesperline, bitsperpixel, NB)
FILE *infile;
unsigned long *cols, *nlines, *bytesperline, *bitsperpixel, *NB;
{
        unsigned long nlines_new, bytesperline_new, numheaderrec;
        unsigned char headerblk[512];
        int i;

        if (fread(headerblk, 512, 1, infile) == 0)
                pm_error("cannot read gould header" );

        *nlines       = (headerblk[3]<<8) | headerblk[2];
        *bytesperline = (headerblk[5]<<8) | headerblk[4];
        *bitsperpixel = (headerblk[7]<<8) | headerblk[6];
        numheaderrec  = (headerblk[9]<<8) | headerblk[8];
        nlines_new    = (headerblk[15]<<24)| (headerblk[14]<<16) | (headerblk[13]<<8) | (headerblk[12]);
        bytesperline_new = (headerblk[19]<<24)| (headerblk[18]<<16) | (headerblk[17]<<8) | (headerblk[16]);
        *NB           = (headerblk[23]<<24)| (headerblk[22]<<16) | (headerblk[21]<<8) | (headerblk[20]);

        if (numheaderrec > 1)
                for (i = 1 ; i <numheaderrec; ++i)
                        if (fread(headerblk, 512, 1, infile) == 0)
                                pm_error("cannot read gould header(2nd)" );

        if (*nlines==0) *nlines=nlines_new;
        if (*bytesperline==0) *bytesperline=bytesperline_new;

        *cols = (*bytesperline)*8 / (*bitsperpixel);
}



