1 #include "mrilib.h"
2
main(int argc,char * argv[])3 int main( int argc , char * argv[] )
4 {
5 float mfrac=0.50 ;
6 double dsum ;
7 int nvox , iarg=1 , hist[32768] , ii,npos=0 , ncut,nmed,kk,ib , qq,nold ;
8 THD_3dim_dataset * dset ;
9 short * sar ;
10
11 if( argc < 2 || strcmp(argv[1],"-help") == 0 ){
12 printf("Usage: mcrawl [-mfrac x] dataset\n"); exit(0);
13 }
14
15 if( strcmp(argv[iarg],"-mfrac") == 0 ){
16 mfrac = strtod( argv[++iarg] , NULL ) ;
17 if( mfrac <= 0.0 ){ fprintf(stderr,"ILLEGAL -mfrac\n");exit(1);}
18 if( mfrac >= 1.0 ) mfrac *= 0.01 ;
19 iarg++ ;
20 }
21
22 dset = THD_open_dataset(argv[iarg]) ;
23 if( !ISVALID_DSET(dset) ){ fprintf(stderr,"CAN'T open dataset\n");exit(1);}
24 if( DSET_BRICK_TYPE(dset,0) != MRI_short ){ fprintf(stderr,"ILLEGAL dataset type\n");exit(1); }
25 DSET_load(dset) ;
26 if( !DSET_LOADED(dset) ){ fprintf(stderr,"CAN'T load dataset\n");exit(1);}
27 sar = DSET_ARRAY(dset,0) ;
28
29 nvox = DSET_NVOX(dset) ;
30 memset( hist , 0 , sizeof(int)*32768 ) ;
31
32 dsum = 0.0 ;
33 for( ii=0 ; ii < nvox ; ii++ ){
34 if( sar[ii] > 0 ){
35 hist[sar[ii]]++ ; dsum += (double)(sar[ii])*(double)(sar[ii]) ; npos++ ;
36 }
37 }
38
39 DSET_unload(dset) ;
40
41 printf("npos = %d\n",npos) ; if( npos <= 99 ) exit(1) ;
42
43 qq = 0.65 * npos ; ib = rint(0.5*sqrt(dsum/npos)) ;
44 for( kk=0,ii=32767 ; ii >= ib && kk < qq ; ii-- ) kk += hist[ii] ;
45
46 ncut = ii ; qq = 0 ;
47 do{
48 for( npos=0,ii=ncut ; ii < 32768 ; ii++ ) npos += hist[ii] ;
49 npos /= 2 ; /* find median */
50 for( kk=0,ii=ncut ; ii < 32768 && kk < npos ; ii++ ) kk += hist[ii] ;
51 printf("ncut=%d ii=%d kk=%d\n",ncut,ii,kk) ;
52 nold = ncut ;
53 ncut = mfrac * ii ;
54 qq++ ;
55 } while( qq < 20 && ncut != nold ) ;
56
57 exit(0) ;
58 }
59