This is mgrtopbm.c in view mode; [Download] [Up]
/* mgrtopbm.c - read a MGR bitmap and produce a portable bitmap
**
** Copyright (C) 1989 by Jef Poskanzer.
**
** 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 "pbm.h"
#include "mgr.h"
static void getinit ARGS(( FILE* file, int* colsP, int* rowsP, int* depthP, int* padrightP ));
static bit getbit ARGS(( FILE* file ));
int
main( argc, argv )
int argc;
char* argv[];
{
FILE* ifp;
bit* bitrow;
register bit* bP;
int rows, cols, depth, padright, row, col;
pbm_init( &argc, argv );
if ( argc > 2 )
pm_usage( "[mgrfile]" );
if ( argc == 2 )
ifp = pm_openr( argv[1] );
else
ifp = stdin;
getinit( ifp, &cols, &rows, &depth, &padright );
if ( depth != 1 )
pm_error( "MGR file has depth of %d, must be 1", depth );
pbm_writepbminit( stdout, cols, rows, 0 );
bitrow = pbm_allocrow( cols );
for ( row = 0; row < rows; row++ )
{
/* Get data, bit-reversed within each byte. */
for ( col = 0, bP = bitrow; col < cols; col++, bP++ )
*bP = getbit( ifp );
/* Discard line padding */
for ( col = 0; col < padright; col ++ )
(void) getbit( ifp );
pbm_writepbmrow( stdout, bitrow, cols, 0 );
}
pm_close( ifp );
pm_close( stdout );
exit( 0 );
}
static unsigned char item;
static int bitsperitem, bitshift;
static void
getinit( file, colsP, rowsP, depthP, padrightP )
FILE* file;
int* colsP;
int* rowsP;
int* depthP;
int* padrightP;
{
struct b_header head;
int pad;
if ( fread( &head, sizeof(struct old_b_header), 1, file ) != 1 )
pm_perror( "reading header" );
if ( head.magic[0] == 'y' && head.magic[1] == 'z' )
{ /* new style bitmap */
if ( fread( &head.depth, sizeof(head) - sizeof(struct old_b_header), 1, file ) != 1 )
pm_perror( "reading rest of header" );
*depthP = (int) head.depth - ' ';
pad = 8;
}
else if ( head.magic[0] == 'x' && head.magic[1] == 'z' )
{ /* old style bitmap with 32-bit padding */
*depthP = 1;
pad = 32;
}
else if ( head.magic[0] == 'z' && head.magic[1] == 'z' )
{ /* old style bitmap with 16-bit padding */
*depthP = 1;
pad = 16;
}
else if ( head.magic[0] == 'z' && head.magic[1] == 'y' )
{ /* old style 8-bit pixmap with 16-bit padding */
*depthP = 8;
pad = 16;
}
else
pm_error(
"bad magic chars in MGR file: '%c%c'",
head.magic[0], head.magic[1] );
*colsP = ( ( (int) head.h_wide - ' ' ) << 6 ) + ( (int) head.l_wide - ' ' );
*rowsP = ( ( (int) head.h_high - ' ' ) << 6 ) + ( (int) head.l_high - ' ' );
*padrightP = ( ( *colsP + pad - 1 ) / pad ) * pad - *colsP;
bitsperitem = 8;
}
static bit
getbit( file )
FILE* file;
{
bit b;
if ( bitsperitem == 8 )
{
item = getc( file );
bitsperitem = 0;
bitshift = 7;
}
bitsperitem++;
b = ( ( item >> bitshift) & 1 ) ? PBM_BLACK : PBM_WHITE;
bitshift--;
return b;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.