Introduction

 

Magnifying glass in the image

 

View more images

 

Geometrical transforms

 

Brightness profile

 

Histogram

 »

Fourier transform

 

Features

 

Brightness/contrast corrrections

 

Flat-Field corrections

 

Inhomogeneous lighting correction

 

Gama correction

 

Noise generation

 

Arithmetical and logical operation

 

Look Up Tables

 

2D convolution

 

Objects drawing

 

Morphological operations

 

Nonlinear filters

 

Bit fields

 

Sobel edge detection

 

Averaging

 

Colour images

 

 MIPS 2.0 - Medical/Microscopy Image Processing Software

 

 

 »

Spectrum view

 

Filtration

 

 

SPECTRUM VIEW


Discrete Fourier Transform / Spectrum

In this window we can perform image conversion to spectral domain, spectral filtering and back transformation. Since the Fast Fourier Transform algorithm is one of the most time consuming operations implemented in MIPS 2.0, the Progress Bar was used as a graphical indicator of the operation's progress.

When moving the mouse over the window with the centred spectrum, it is possible to observe the values of the Fourier transform coefficients in the bottom bar. Their form can be set in Options. The Scale value changes the dynamic range of the brightness of the points representing the Fourier transform coefficients.

In addition to displaying the coefficients when moving the mouse cursor on the bottom bar, you can also use a special window to display them. After entering the coordinates, the real and imaginary components, absolute value and phase are displayed.

Window Save coefficents allows you to save the values of the selected coefficients in an ASCI file so that the results of the Fourier transform can be analyzed later.  

Preview

 

 

                Spectrum view

 

 

 

 

                         DFT settings

 

 

 

 

             Window for coefficients view

 

 

 

 

         Saving of selected coefficients to the file

Examples

 

 

 

                  Image spectrum

 

 

 

   Backward-transformed image - normal mode

 

 

 

Backward-transformed image - constant amplitude

 

 

 

Backward-transformed image - constant phase

 

 


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