Can Eigenvalue Centrality Detect Blobs in Images?

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SUMMARY

The discussion centers on the application of eigenvalue centrality for detecting blobs in images based on color relationships. An adjacency matrix is utilized to represent connections, where values indicate the strength of relationships among pixels. The feasibility of using eigenvector centrality for blob detection is questioned, highlighting that the method requires computing eigenvectors of a sparse matrix sized PixelNumber x PixelNumber. The use of preconditioned conjugate gradient methods is suggested for this computation, although it is acknowledged to be complex.

PREREQUISITES
  • Understanding of adjacency matrices in network theory
  • Familiarity with eigenvector centrality concepts
  • Knowledge of image processing techniques for blob detection
  • Experience with sparse matrix computations
NEXT STEPS
  • Research eigenvalue decomposition methods for sparse matrices
  • Explore preconditioned conjugate gradient algorithms
  • Learn about alternative blob detection techniques that do not rely on corners
  • Investigate the application of network theory in image analysis
USEFUL FOR

Data scientists, image processing engineers, and researchers interested in advanced feature detection methods in computer vision.

NotASmurf
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Hey all, I just read up on the principle of centrality, where

"Think of a "network" as an NxN matrix, which has information about how N people (or N pages or N countries..) are connected to each other.

Adjacency Matrix is an NxN matrix, let's say it looks something like this. People who aren't connected to each other have A[j] = 0, people with weak relationships have A[j] = 0.1, people with medium ties have A[j]=0.4,
people with strong ties have A[j] = 0.6
1---2----3----4
1---0.0 0.1 0.4 0.6
2---0.1 0.0 0.4 0.0
3---0.4 0.4 0.0 0.1
4---0.6 0.0 0.1 0.0

1 and 2 are weakly connected, 1 and 3 have medium ties, 1 and 4 have strong ties. This is just a quick example to give you a quick idea. These matrices may not always be symmetric either.

People with "higher eigenvector centrality" are people who are better connected to each other. This takes into account, not just how many people the person knows, but also whom the person knows.'

Is it feasible to use this to locate blobs in images using their color relations to each other? I need a feature detector/ blob extractor that doesn't use corners so I saw this. Any advice appreciated.
 
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How do you plan to use it? The eigenvectors don't care about order, so the concept of "being next to each other" (which is relevant if you look for features) doesn't translate well to the matrix problem.
 
What is the final goal ? Send a picture, i will see if there is no simpler method.
The method you are explaining need to compute eigen vector of a sparse matrix of size PixelNumber * PixelNumber. You can use préconjugate gradient but it's not easy.
 

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