Help with some basic question

Hello to everybody, i’m starting to using ImageJ at university, searching to understand its basic principles.
I have to answer to some question to do an exam and i would like to have some help by someone that knows this topic mich better than me.
I’ll be very grateful to everybody will be so kind to help me.

These are the question:

  1. What is the difference between electronic processing of an image and its visualization/representation

  2. Discuss the difference between changing brightness and contrast of an image. Do these operations change the information contained in an image?

  3. Which ones among the following imply a loss or a modification of the information contained in an image: binarizing, changing the LUT (Look Up Table), image inversion, background subtraction.

  4. Can one perform an image inversion without changing the raster? What analogous operations can I do without affecting the image content?

  5. What is it meant by image calibration? Describe at least two operations that can be performed thanks to the calibration.

  6. What does it mean to binarize an image and which are the steps necessary to do so? Describe at least two applications of this operation.

  7. Give the pros and cons of background subtraction. Describe at least one strategy to determine the background and subtract it. Give an example of an application.

  8. Describe a procedure for extracting the number and geometrical features of objects in a digital image.
    What does it mean to subtract images? Describe three applications.

Hi @anna,

How about we do it like this: Answer each question to the best of your knowledge here and we’ll chip in to provide details and corrections as needed.
Welcome to the forum :smile:


That is not an appropriate request. You are confusing the purpose of this forum.