JuliaImages / JuliaImages/ImageFiltering.jl

Linear extrapolation for boundary values?

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Dominant language
Julia
Stars
104
Forks
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No merged PRs in 30d

Description

The image padding machinery doesn't allow for extrapolation. This causes significant errors in the calculation of the derivative at the border, as noted in the documentation:

Ignore the values at the border since we expect them to be erroneous.

I took a look at the source to see whether I could bang out a fix in an hour, but was stymied by how heavily the current padding framework relies on indexing. Any suggestions on how one would implement this boundary condition?

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  3. Fork the repository and make your change on a branch.
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Research direction

Start with the imgradients documentation and the current image padding framework, especially how indexing handles boundary values. Determine how a linear extrapolation boundary condition should interact with derivative calculation, then verify that border derivatives no longer require ignoring the boundary.

Written by the indexing model from the issue text.

Assessment

Tech stack
julia
Domain
computer-vision
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
30/100

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