PDLPorters / PDLPorters/pdl

SF feature request #77 - more efficient single pass algorithm for ccNcompt

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Dominant language
Perl
Stars
105
Forks
49
PR merge metrics
No merged PRs in 30d

Description

https://sourceforge.net/p/pdl/feature-requests/77/

ccNcompt currently uses a 2-pass algorithm, but there is a more efficient single pass algorithm described in "A linear-time component-labeling algorithm using contour tracing technique" (2004):
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.95.6330

And here is an implementation in C: http://www.codeproject.com/Tips/407172/Connected-Component-Labeling-and-Vectorization

There's also pseudocode in the wikipedia article: https://en.wikipedia.org/wiki/Connected-component_labeling#Pseudocode_for_the_one-component-at-a-time_algorithm

Karl adds:

That's fine to add a new one pass algorithm but please give it a new function name! (The old one has stood the test of time.)

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by locating the existing ccNcompt implementation and reviewing the linked paper, C implementation, and pseudocode for the proposed single-pass approach. Add the algorithm under a new function name while preserving the existing function, and verify that connected-component labeling remains correct.

Written by the indexing model from the issue text.

Assessment

Tech stack
perl
Domain
computer-vision
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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