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

static ProcessorNEW ()

Static Public Attributes

static 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 3767 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 3781 of file processor.h.

03782                 {
03783                         return "Ramp processor -- Fits a least-squares plane "
03784                                    "to the picture, and subtracts the plane from "
03785                                    "the picture.  A wedge-shaped overall density "
03786                                    "profile can thus be removed from the picture.";
03787                 }

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 3772 of file processor.h.

References NAME.

Referenced by process_inplace().

03773                 {
03774                         return NAME;
03775                 }

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

Definition at line 3776 of file processor.h.

03777                 {
03778                         return new RampProcessor();
03779                 }

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 8096 of file processor.cpp.

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

08097 {
08098         if (!image) {
08099                 return;
08100         }
08101 
08102         int nz = image->get_zsize();
08103         if (nz > 1) {
08104                 LOGERR("%s Processor doesn't support 3D model", get_name().c_str());
08105                 throw ImageDimensionException("3D model not supported");
08106         }
08107 
08108         int nsam = image->get_xsize();
08109         int nrow = image->get_ysize();
08110         int n1 = nsam / 2;
08111         double sx1 = double(n1)*double(nsam+1);
08112         if ( nsam % 2 == 1 )
08113                 sx1 += 1 + n1;
08114         sx1 *= nrow;
08115         int n2 = nrow / 2;
08116         double sx2 = double(n2)*double(nrow+1);
08117         if ( nrow % 2 == 1 )
08118                 sx2 += 1 + n2;
08119         sx2 *= nsam;
08120         float *data = image->get_data();
08121         float *row = NULL; // handy pointer for values in a specific row of the data
08122         // statistical sums
08123         double syx1 = 0, syx2 = 0, sy = 0, sx1q = 0, sx2q = 0, syq = 0;
08124         for (int j=1; j <= nrow; j++) {
08125                 row = data + (j-1)*nsam - 1; // "-1" so that we can start counting at 1
08126                 for (int i=1; i<=nsam; i++) {
08127                         syx1 += row[i]*i;
08128                         syx2 += row[i]*j;
08129                         sy += row[i];
08130                         sx1q += i*i;
08131                         sx2q += j*j;
08132                         syq += row[i]*double(row[i]);
08133                 }
08134         }
08135         // least-squares
08136         float dn = float(nsam)*float(nrow);
08137         double qyx1 = syx1 - sx1*sy / dn;
08138         double qyx2 = syx2 - sx2*sy / dn;
08139         double qx1x2 = 0.0;
08140         double qx1 = sx1q - sx1*sx1 / dn;
08141         double qx2 = sx2q - sx2*sx2 / dn;
08142         double qy = syq - sy*sy / dn;
08143         double c = qx1*qx2 - qx1x2*qx1x2;
08144         if ( c > FLT_EPSILON ) {
08145                 double b1 = (qyx1*qx2 - qyx2*qx1x2) / c;
08146                 double b2 = (qyx2*qx1 - qyx1*qx1x2) / c;
08147                 double a = (sy - b1*sx1 - b2*sx2) / dn;
08148                 double d = a + b1 + b2;
08149                 for (int i=1; i<=nrow; i++) {
08150                         qy = d;
08151                         row = data + (i-1)*nsam - 1;
08152                         for (int k=1; k<=nsam; k++) {
08153                                 row[k] -= static_cast<float>(qy);
08154                                 qy += b1;
08155                         }
08156                         d += b2;
08157                 }
08158         } // image not altered if c is zero
08159 
08160         image->update();
08161 }


Member Data Documentation

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

Definition at line 3789 of file processor.h.

Referenced by get_name().


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