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EMAN::RampProcessor Class Reference

Ramp processor -- Fits a least-squares plane to the picture, and subtracts the plane from the picture. More...

#include <processor.h>

Inheritance diagram for EMAN::RampProcessor:

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Collaboration diagram for EMAN::RampProcessor:

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List of all members.

Public Member Functions

void process_inplace (EMData *image)
 To process an image in-place.
string get_name () const
 Get the processor's name.
string get_desc () const
 Get the descrition of this specific processor.

Static Public Member Functions

ProcessorNEW ()

Static Public Attributes

const string NAME = "filter.ramp"

Detailed Description

Ramp processor -- Fits a least-squares plane to the picture, and subtracts the plane from the picture.

A wedge-shaped overall density profile can thus be removed from the picture.

Definition at line 3595 of file processor.h.


Member Function Documentation

string EMAN::RampProcessor::get_desc  )  const [inline, virtual]
 

Get the descrition of this specific processor.

This function must be overwritten by a subclass.

Returns:
The description of this processor.

Implements EMAN::Processor.

Definition at line 3609 of file processor.h.

03610                 {
03611                         return "Ramp processor -- Fits a least-squares plane "
03612                                    "to the picture, and subtracts the plane from "
03613                                    "the picture.  A wedge-shaped overall density "
03614                                    "profile can thus be removed from the picture.";
03615                 }

string EMAN::RampProcessor::get_name  )  const [inline, virtual]
 

Get the processor's name.

Each processor is identified by a unique name.

Returns:
The processor's name.

Implements EMAN::Processor.

Definition at line 3600 of file processor.h.

Referenced by process_inplace().

03601                 {
03602                         return NAME;
03603                 }

Processor* EMAN::RampProcessor::NEW  )  [inline, static]
 

Definition at line 3604 of file processor.h.

03605                 {
03606                         return new RampProcessor();
03607                 }

void RampProcessor::process_inplace EMData image  )  [virtual]
 

To process an image in-place.

For those processors which can only be processed out-of-place, override this function to just print out some error message to remind user call the out-of-place version.

Parameters:
image The image to be processed.

Implements EMAN::Processor.

Definition at line 7828 of file processor.cpp.

References data, EMAN::EMData::get_data(), get_name(), EMAN::EMData::get_xsize(), EMAN::EMData::get_ysize(), EMAN::EMData::get_zsize(), ImageDimensionException, LOGERR, and EMAN::EMData::update().

07829 {
07830         if (!image) {
07831                 return;
07832         }
07833 
07834         int nz = image->get_zsize();
07835         if (nz > 1) {
07836                 LOGERR("%s Processor doesn't support 3D model", get_name().c_str());
07837                 throw ImageDimensionException("3D model not supported");
07838         }
07839 
07840         int nsam = image->get_xsize();
07841         int nrow = image->get_ysize();
07842         int n1 = nsam / 2;
07843         double sx1 = double(n1)*double(nsam+1);
07844         if ( nsam % 2 == 1 )
07845                 sx1 += 1 + n1;
07846         sx1 *= nrow;
07847         int n2 = nrow / 2;
07848         double sx2 = double(n2)*double(nrow+1);
07849         if ( nrow % 2 == 1 )
07850                 sx2 += 1 + n2;
07851         sx2 *= nsam;
07852         float *data = image->get_data();
07853         float *row = NULL; // handy pointer for values in a specific row of the data
07854         // statistical sums
07855         double syx1 = 0, syx2 = 0, sy = 0, sx1q = 0, sx2q = 0, syq = 0;
07856         for (int j=1; j <= nrow; j++) {
07857                 row = data + (j-1)*nsam - 1; // "-1" so that we can start counting at 1
07858                 for (int i=1; i<=nsam; i++) {
07859                         syx1 += row[i]*i;
07860                         syx2 += row[i]*j;
07861                         sy += row[i];
07862                         sx1q += i*i;
07863                         sx2q += j*j;
07864                         syq += row[i]*double(row[i]);
07865                 }
07866         }
07867         // least-squares
07868         float dn = float(nsam)*float(nrow);
07869         double qyx1 = syx1 - sx1*sy / dn;
07870         double qyx2 = syx2 - sx2*sy / dn;
07871         double qx1x2 = 0.0;
07872         double qx1 = sx1q - sx1*sx1 / dn;
07873         double qx2 = sx2q - sx2*sx2 / dn;
07874         double qy = syq - sy*sy / dn;
07875         double c = qx1*qx2 - qx1x2*qx1x2;
07876         if ( c > FLT_EPSILON ) {
07877                 double b1 = (qyx1*qx2 - qyx2*qx1x2) / c;
07878                 double b2 = (qyx2*qx1 - qyx1*qx1x2) / c;
07879                 double a = (sy - b1*sx1 - b2*sx2) / dn;
07880                 double d = a + b1 + b2;
07881                 for (int i=1; i<=nrow; i++) {
07882                         qy = d;
07883                         row = data + (i-1)*nsam - 1;
07884                         for (int k=1; k<=nsam; k++) {
07885                                 row[k] -= static_cast<float>(qy);
07886                                 qy += b1;
07887                         }
07888                         d += b2;
07889                 }
07890         } // image not altered if c is zero
07891 
07892         image->update();
07893 }


Member Data Documentation

const string RampProcessor::NAME = "filter.ramp" [static]
 

Definition at line 129 of file processor.cpp.


The documentation for this class was generated from the following files:
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