# Tag Info

### How to Calculate Total Variation (TV) of an Image?

can use MATLAB function imgradientxy. [Gx,Gy] = imgradientxy(I). This will return the x and y derivative of image I.
1 vote

### What's the difference between SIFT and general stereo matching algorithm (eg, sgbm)?

After weeks of reading, researching and experiments, now I have more knowledge to answer my own question. Both of SIFT and SGBM can be used to find matching points but they are very different in the ...
• 131
1 vote

### Any good alternatives of ImageJ (Fiji)?

If you’re looking for a large collection of image processing functionality geared towards quantification, I will recommend DIPlib (I’m an author). It is different from ImageJ in that it doesn’t have a ...
• 1,077
1 vote
Accepted

### Any good alternatives of ImageJ (Fiji)?

I used to recommend ICY from Institut Pasteur, mostly dedicated to biomedical image analysis, it was active in June 2022, and CImg Library - C++ Template Image Processing Toolkit, a small and open-...
• 30.2k
1 vote
Accepted

### Wider sharpening filter

There are two basic forms of sharpening filter: I - 𝛼 Laplace(I) k I - (k-1) smooth(I) where I is the image, 𝛼 is a positive value, and k is a value larger than 1. The first form is referenced by ...
• 1,077

### Wider sharpening filter

A classical construction for a linear sharpening filter $S$ is a weighted combination of some averaging $A$ (potentially an identity operator, performing no averaging) augmented by a certain amount ...
• 30.2k

### Signal/image processing using python?Additional IDE must required or default pyhton IDLE is sufficent?

VSCode is your best bet for python DSP development. It offers a rich set of tools, and works well with a variety of other languages, and version control (i.e., git).

### Signal/image processing using python?Additional IDE must required or default pyhton IDLE is sufficent?

Jupyter Notebooks which isn't an IDE (Integrated Development Environment) is my peferred solution for doing interactive work with signal processing and plotting . You can mix rich graphics and ...
• 37.7k

### How to add a fake thermal effect to images

Please modify below line to get colors with RGBA values holds $\left( 0 \sim 255 \right)$. colors = scalarMap.to_rgba(gray) to ...
Accepted

### Image warping with heat map that "pulls" on pixels

Ok, I found what seems to be a decently principled and fast (roughly O(height*width)) solution - result here. I assume it has some pre-existing name in the ...
• 143

### Which Blur is being used in this effect

So I tried what has been suggested on this image Here's the python code : ...

### Which Blur is being used in this effect

It's not a blur; as you can see in your size=0 example, this has to do something with a cyclic half-image shift of the shape and something like XOR-ing the pattern with itself. Maybe afterwards a ...
• 26.6k

### Why are real-world digital images not bandlimited?

This is an old chestnut. One of the earlier (but relatively recent) musings about this topic for general signals is Slepian's On Bandwidth.. A screenshot of the abstract is below.
• 22.9k

### Why are real-world digital images not bandlimited?

The statement is either misleading or wrong, depending on interpretation. I defer to this answer for details, and for short version I cite my comments from under this answer What I'm saying is, it's ...
• 5,310

### Why are real-world digital images not bandlimited?

The notion of "digital image" is not so precise, when talking about some 2D multidimensional signal. One instance I know of is a seismic gather: a line of surface-based sensors, located ...
• 30.2k

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