Thursday, July 21, 2022

Playing with Phase and Magnitude


In this series dedicated to the Fourier Transform, it is important to understand the role played by magnitude (or amplitude) and phase in an image...

Wednesday, July 20, 2022

Model bias in cryo-EM - Einstein from noise

In the article of Maxim Shatsky et al.  entitled "A Method for the Alignment of Heterogeneous Macromolecules from Electron Microscopy" (J Struct Biol. 2009, 166(1): 67–78. doi:10.1016/j.jsb.2008.12.008.), the authors show that pure noise images aligned to a reference image give an average image resembling the reference. This is a perfect example of the model bias occurring during the 2D classification step. Let's do it!!!

Cryo-EM Table of Contents

Section dedicated to Cryo-Electron Microscopy and ImageJ

Thursday, June 30, 2022

Case study: The target

In this case study, we want to count the number of points obtained in this shooting session.

Thursday, January 14, 2021

Normal Map of a sphere using ImageJ

 A small script for creating a normal map of a sphere using ImageJ.

Friday, November 13, 2020

Rank Filters

Denoising images is not restricted to linear filters, another family of filters is powerful for such an image enhancement: the Rank Filters.

Thursday, November 12, 2020

Noise Distributions


Noise present in  a scientific image can be described depending of its distribution. Thus, it is important to figure out how to define the type of noise in order to elaborate a strategy to denoise the images...