Docs: Issue Examples Gallery – correct asset URLs, contributing guide, and gallery structure

[PredictiveManish]

Summary

🎯 Purpose: Describe the objective of your changes in this Pull-Request.
Closes #194
📜 Example Usage: If adding new functionality, strive to provide a minimal working example (MWE) that demonstrates end-to-end usage and output of your new methods. If creating a MWE is not feasible, a conceptual code snippet showcasing the usage is also appreciated. Ensure that the code provided can be copied, pasted, and run without modifications.

Purpose: Add a static docs page that acts as a continuously growing gallery of example images for each issue type detected by CleanVision. Images are stored in the cleanlab/assets repo (not in CleanVision). This PR (1) fixes the Issue Examples Gallery to use the image URLs that actually exist in that repo, (2) adds clear instructions for contributors on how to add more examples, and (3) documents where to source images (e.g. running CleanVision on datasets, Kaggle, blog posts). No new code or APIs; documentation and CONTRIBUTING updates only.

(No runnable code—docs-only change. The gallery is viewed at the built docs URL, e.g. Issue Examples Gallery under Tutorials.)

Impact

🌐 Areas Affected: Enumerate modules, functions, or documentation impacted by your code.

👥 Who’s Affected: Mention who might be impacted (if applicable).

Areas affected:

• docs/source/issue_examples.rst — Rewritten to use correct asset filenames (blurry.png, dark.jpg, light.jpg, etc.) from cleanlab/assets, intro/contributing note, and an “Adding more examples” section.
• CONTRIBUTING.md — New “Documentation and example images” subsection under Pull Requests pointing to the assets repo and the gallery’s “Adding more examples” section.

Who’s affected: Docs readers and contributors who want to view or add compelling example images per issue type (Blurry, Dark, Light, Grayscale, Low Information, Odd Aspect Ratio, Odd Size, Exact Duplicates, Near Duplicates).

Screenshots

📸 If your changes modify documentation or a tutorial notebook, please include screenshots or GIFs showing the rendered outputs for a quicker initial review, highlighting the main changes.

• Screenshot of the rendered Issue Examples Gallery page (intro + at least one subsection, e.g. Blurry or Dark) after building the docs.
• Optional: Screenshot of the CONTRIBUTING.md section “Documentation and example images.”

Testing

🔍 Testing Done: Outline what kinds of tests you performed.

🔗 Test Case Link: Directly link to the most end-to-end check of your new functionality.

Testing done: Built the Sphinx docs locally (cd docs && make html or equivalent) and confirmed (1) the Issue Examples Gallery builds without RST errors, (2) images load from https://raw.githubusercontent.com/cleanlab/assets/master/cleanvision/example_issue_images/, and (3) CONTRIBUTING.md renders correctly.

Unaddressed Cases

It's ok if your unit tests are not yet comprehensive when you first open the PR, we can revisit them later!

⚠️ Mention any aspects of testing that have not been covered, and why.

• No automated tests were added (docs-only). Read-the-Docs or CI doc build (if present) serves as the main check.

Links to Relevant Issues or Conversations

🔗 What Git or Slack items (Issues, threads, etc) that are specifically related to this work? Please link them here.

References

📚 Include any extra information that may be helpful to reviewers of your Pull-Request here (e.g. relevant URLs or Wiki pages that could help give background information).

Share links, docs, or sources that facilitated your changes.

• Image storage (no images in CleanVision repo): cleanlab/assets – cleanvision/example_issue_images
• Raw image URL pattern: https://raw.githubusercontent.com/cleanlab/assets/master/cleanvision/example_issue_images/<filename>
• Example sources mentioned on the page: Kaggle search (cleanvision), CleanVision blog post (João Ataíde)

Reviewer Notes

💡 Include any specific points for the reviewer to consider during their review.

• Confirm that the nine issue-type subsections and the “Adding more examples” instructions are clear and match how you want the gallery to grow.
• If the assets repo later adds more files (e.g. blurry_2.jpg, dark_food101.jpg), new .. figure:: blocks can be added in the same pattern in issue_examples.rst; no further template changes are required.

[CLAassistant]

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