jimp-dev/jimp

Even sized kernel support

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#749 opened on Jun 7, 2019

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enhancementhelp wanted

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Description

Is your feature request related to a problem? Please describe. It would be useful to have even sized kernel support for convolution etc.

Describe the solution you'd like The implementation could follow Matlabs imfilter/conv2 algorithm. Imfilter(M, k) result is same as conv2(M, k, 'same').

Matlabs documentation states: "If you specify an even-sized kernel h, then the center of the kernel is floor((size(h) + 1)/2).

For example, the center of 4-element filter [0.25 0.75 -0.75 -0.25] is the second element, 0.75. This filter gives identical results as filtering with the 5-element filter [0 0.25 0.75 -0.75 -0.25]."

https://se.mathworks.com/help/images/ref/imfilter.html

Contributor guide

Research direction
Implement even sized kernel support for convolution by adapting the algorithm from MATLAB's imfilter/conv2. The center index for an even sized kernel is floor((size+1)/2). Ensure consistent behavior by padding or shifting as described.
Tech stack
javascript
Domain
backend
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
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Fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
GitJavaScript
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75