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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 3720 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 3734 of file processor.h.

03735                 {
03736                         return "Ramp processor -- Fits a least-squares plane "
03737                                    "to the picture, and subtracts the plane from "
03738                                    "the picture.  A wedge-shaped overall density "
03739                                    "profile can thus be removed from the picture.";
03740                 }

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 3725 of file processor.h.

Referenced by process_inplace().

03726                 {
03727                         return NAME;
03728                 }

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

Definition at line 3729 of file processor.h.

03730                 {
03731                         return new RampProcessor();
03732                 }

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 7944 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().

07945 {
07946         if (!image) {
07947                 return;
07948         }
07949 
07950         int nz = image->get_zsize();
07951         if (nz > 1) {
07952                 LOGERR("%s Processor doesn't support 3D model", get_name().c_str());
07953                 throw ImageDimensionException("3D model not supported");
07954         }
07955 
07956         int nsam = image->get_xsize();
07957         int nrow = image->get_ysize();
07958         int n1 = nsam / 2;
07959         double sx1 = double(n1)*double(nsam+1);
07960         if ( nsam % 2 == 1 )
07961                 sx1 += 1 + n1;
07962         sx1 *= nrow;
07963         int n2 = nrow / 2;
07964         double sx2 = double(n2)*double(nrow+1);
07965         if ( nrow % 2 == 1 )
07966                 sx2 += 1 + n2;
07967         sx2 *= nsam;
07968         float *data = image->get_data();
07969         float *row = NULL; // handy pointer for values in a specific row of the data
07970         // statistical sums
07971         double syx1 = 0, syx2 = 0, sy = 0, sx1q = 0, sx2q = 0, syq = 0;
07972         for (int j=1; j <= nrow; j++) {
07973                 row = data + (j-1)*nsam - 1; // "-1" so that we can start counting at 1
07974                 for (int i=1; i<=nsam; i++) {
07975                         syx1 += row[i]*i;
07976                         syx2 += row[i]*j;
07977                         sy += row[i];
07978                         sx1q += i*i;
07979                         sx2q += j*j;
07980                         syq += row[i]*double(row[i]);
07981                 }
07982         }
07983         // least-squares
07984         float dn = float(nsam)*float(nrow);
07985         double qyx1 = syx1 - sx1*sy / dn;
07986         double qyx2 = syx2 - sx2*sy / dn;
07987         double qx1x2 = 0.0;
07988         double qx1 = sx1q - sx1*sx1 / dn;
07989         double qx2 = sx2q - sx2*sx2 / dn;
07990         double qy = syq - sy*sy / dn;
07991         double c = qx1*qx2 - qx1x2*qx1x2;
07992         if ( c > FLT_EPSILON ) {
07993                 double b1 = (qyx1*qx2 - qyx2*qx1x2) / c;
07994                 double b2 = (qyx2*qx1 - qyx1*qx1x2) / c;
07995                 double a = (sy - b1*sx1 - b2*sx2) / dn;
07996                 double d = a + b1 + b2;
07997                 for (int i=1; i<=nrow; i++) {
07998                         qy = d;
07999                         row = data + (i-1)*nsam - 1;
08000                         for (int k=1; k<=nsam; k++) {
08001                                 row[k] -= static_cast<float>(qy);
08002                                 qy += b1;
08003                         }
08004                         d += b2;
08005                 }
08006         } // image not altered if c is zero
08007 
08008         image->update();
08009 }


Member Data Documentation

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

Definition at line 132 of file processor.cpp.


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