1 /*****************************************************************************
2 Major portions of this software are copyrighted by the Medical College
3 of Wisconsin, 1994-2000, and are released under the Gnu General Public
4 License, Version 2. See the file README.Copyright for details.
5 ******************************************************************************/
6
7 #include "mrilib.h"
8
main(int argc,char * argv[])9 int main( int argc , char *argv[] )
10 {
11 MRI_IMAGE *im , *imb ;
12 int narg ;
13 float perc=0.0 ;
14
15 if( argc < 2 || strncmp(argv[1],"-help",2) == 0 ){
16 printf( "Converts an image to raw pgm format.\n") ;
17 printf( "Results go to stdout and should be redirected.\n");
18 printf( "Usage: mritopgm [-pp] input_image\n" ) ;
19 printf( "Example: mritopgm fred.001 | ppmtogif > fred.001.gif\n") ;
20 printf( "\n"
21 " The '-pp' option expresses a clipping percentage.\n"
22 " That is, if this option is given, the pp%%-brightest\n"
23 " pixel is mapped to white; all above it are also white,\n"
24 " and all below are mapped linearly down to black.\n"
25 " The default is that pp=100; that is, the brightest\n"
26 " pixel is white. A useful operation for many MR images is\n"
27 " mritopgm -99 fred.001 | ppmtogif > fred.001.gif\n"
28 " This will clip off the top 1%% of voxels, which are often\n"
29 " super-bright due to arterial inflow effects, etc.\n"
30 ) ;
31 exit(0) ;
32 }
33
34 machdep() ;
35
36 narg = 1 ;
37 if( argv[narg][0] == '-' ){
38 perc = 0.01 * strtod(argv[narg]+1,NULL) ;
39 if( perc < 0.01 || perc > 1.00 ){
40 fprintf(stderr,"** Illegal percentage: %s\n",argv[narg]+1) ;
41 }
42 narg++ ;
43 }
44 im = mri_read_just_one( argv[narg] ) ;
45 if( im == NULL ) exit(1) ;
46
47 if( im->kind != MRI_float ){
48 imb = mri_to_float(im) ; mri_free(im) ; im = imb ;
49 }
50
51 if( perc > 0.0 ){
52 float val = mri_quantile( im , perc ) ;
53 float *ar = mri_data_pointer(im) ;
54 int ii ;
55 for( ii=0 ; ii < im->nvox ; ii++ ) if( ar[ii] > val ) ar[ii] = val ;
56 }
57
58 imb = mri_to_byte( im ) ; mri_free( im ) ;
59
60 printf( "P5 %d %d 255\n" , imb->nx , imb->ny ) ;
61 fwrite( MRI_BYTE_PTR(imb) , imb->pixel_size , imb->nx * imb->ny , stdout ) ;
62
63 exit(0) ;
64 }
65