Doxygen Source Code Documentation
Main Page Alphabetical List Data Structures File List Data Fields Globals Search
mritopgm.c
Go to the documentation of this file.00001
00002
00003
00004
00005
00006
00007 #include "mrilib.h"
00008
00009 int main( int argc , char *argv[] )
00010 {
00011 MRI_IMAGE *im , *imb ;
00012 int narg ;
00013 float perc=0.0 ;
00014
00015 if( argc < 2 || strncmp(argv[1],"-help",2) == 0 ){
00016 printf( "Converts an image to raw pgm format.\n") ;
00017 printf( "Results go to stdout and should be redirected.\n");
00018 printf( "Usage: mritopgm [-pp] input_image\n" ) ;
00019 printf( "Example: mritopgm fred.001 | ppmtogif > fred.001.gif\n") ;
00020 printf( "\n"
00021 " The '-pp' option expresses a clipping percentage.\n"
00022 " That is, if this option is given, the pp%%-brightest\n"
00023 " pixel is mapped to white; all above it are also white,\n"
00024 " and all below are mapped linearly down to black.\n"
00025 " The default is that pp=100; that is, the brightest\n"
00026 " pixel is white. A useful operation for many MR images is\n"
00027 " mritopgm -99 fred.001 | ppmtogif > fred.001.gif\n"
00028 " This will clip off the top 1%% of voxels, which are often\n"
00029 " super-bright due to arterial inflow effects, etc.\n"
00030 ) ;
00031 exit(0) ;
00032 }
00033
00034 machdep() ;
00035
00036 narg = 1 ;
00037 if( argv[narg][0] == '-' ){
00038 perc = 0.01 * strtod(argv[narg]+1,NULL) ;
00039 if( perc < 0.01 || perc > 1.00 ){
00040 fprintf(stderr,"** Illegal percentage: %s\n",argv[narg]+1) ;
00041 }
00042 narg++ ;
00043 }
00044 im = mri_read_just_one( argv[narg] ) ;
00045 if( im == NULL ) exit(1) ;
00046
00047 if( perc > 0.0 ){
00048 float val = mri_quantile( im , perc ) ;
00049 int ii ;
00050 switch( im->kind ){
00051 case MRI_short:{
00052 short *ar = mri_data_pointer(im) ;
00053 for( ii=0 ; ii < im->nvox ; ii++ ) if( ar[ii] > val ) ar[ii] = val ;
00054 }
00055 break ;
00056 case MRI_byte:{
00057 byte *ar = mri_data_pointer(im) ;
00058 for( ii=0 ; ii < im->nvox ; ii++ ) if( ar[ii] > val ) ar[ii] = val ;
00059 }
00060 break ;
00061 case MRI_float:{
00062 float *ar = mri_data_pointer(im) ;
00063 for( ii=0 ; ii < im->nvox ; ii++ ) if( ar[ii] > val ) ar[ii] = val ;
00064 }
00065 break ;
00066 default:
00067 fprintf(stderr,"** Don't know how to percent clip this type of image!\n") ;
00068 break ;
00069 }
00070 }
00071
00072 imb = mri_to_byte( im ) ;
00073 mri_free( im ) ;
00074
00075 printf( "P5 %d %d 255\n" , imb->nx , imb->ny ) ;
00076 fwrite( imb->im.byte_data , imb->pixel_size , imb->nx * imb->ny , stdout ) ;
00077
00078 exit(0) ;
00079 }
