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

 

 

 

FLAT - FIELD CORRECTION


Image / Correction / Flat-Field

When processing image data from a digital microscope, there is often a problem with uneven illumination of the slide that is placed under the object being imaged. Using Flat-Field Correction, this undesirable phenomenon can be reduced. First, an image of the desired Io object, including the inhomogeneous background, must be obtained. Then move the slide under the microscope and take a picture of the If background only. Finally, we cover the eyepiece and take a dark image of Ib. The following relation describes the principle of Flat-Field Correction.

    

By the constant Io we change the contrast of the resulting image, If is the resulting image. By using the Ib image, we remove the errors caused by the non-linearity of the image sensor. If we do not have this image available, it is sufficient to use a null field (black area) the size of the Io image. .

When all three images are selected, the Flat-field correction is calculated and the resulting image is displayed. We can also change the output dynamic range of the image - the constant M from the previous relation.

 

Preview

 

 

Example 1

 

                    

  

         Original image                                           Background image

 

 

 

                    

       Image under the low light level                        Image after correction
     conditions (darked image sensor)

Example 2

 

                    

  

         Original image                                           Background image

 

 

 

                    

    Image with darked image sensor                      Image after correction

Example 3

 

                    

  

         Original image                                           Background image

 

 

 

                    

    Image with darked image sensor                      Image after correction

Example 4

 

                    

  

         Original image                                           Background image

 

 

 

                    

    Image with darked image sensor                      Image after correction

 


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