Re-enable PSNR-B metric in Image Comparison Tool

[diksha78dev]

Summary

Re-enables the PSNR-B metric in gui/comparison.py. The metric was previously disabled due to a bug in sewar library that has been fixed since sewar v0.4.4 (July 2020).

Changes

• Updated metrics table from 20 to 21 rows
• Uncommented PSNR-B table setup (row 6) with icon and tooltip
• Replaced try/except error handling with direct sewar.psnrb() call
• Uncommented PSNR-B value display with .2f formatting
• Shifted all subsequent metrics by 1 row to accommodate PSNR-B
• Removed obsolete FIXME comment

Testing

✅ All 13+ metrics compute without errors
✅ PSNR-B correctly displays as "9.48" in table row 6
✅ No commented-out code remaining
✅ Verified with test_psnrb.py

Related

• Closes PSNR-B metric commented out and FIXME references external library bug #12
• Related to sewar issue Launcher messaging about "HexEd.it: Offline cached" is potentially misleading #17: NameError: name 'log2' is not defined while calling psnrb() andrewekhalel/sewar#17

[Gooichand]

✅ Looks good!

However, PR #44 also modifies gui/comparison.py.

To avoid merge conflicts:

Option A: We merge this first (preferred - it's better documented)
Option B: Coordinate with @magic-peach on PR #44 to avoid overlap

Which would you prefer?

[diksha78dev]

I agree — let’s merge PR #44 first since it’s better documented.
I’ll rebase my branch afterward to avoid conflicts. 👍

[Gooichand]

@diksha78dev #44 has some issue afte that i willl merged

[Gooichand]

📢 Important: OSCG-26 Communication Update

Body:
All contributors working on the DGC project, please note:

Nexfellow is now our primary communication platform for OSCG-26.

👉 Important announcement - Please like and follow:
https://www.nexfellow.com/post/698eac9c636efcd987385b54

This post contains critical project updates and information.

Thank you for your contributions! 🙏

[Gooichand]

✅ LGTM - Ready to Merge

Great work fixing the PSNR-B metric! The sewar library bug was resolved in v0.4.4 (July 2020), so it's safe to re-enable this metric.

Changes look good:

• Removed try/except workaround
• Added PSNR-B to metrics table (row 6)
• All 21 metrics now working correctly
• Properly tested with verification script

This restores full functionality to the Image Comparison Tool. Approved for merge! 🎯

[Gooichand]

⚠️ Merge Conflicts Detected

Hi @diksha78dev! Great work on this PR, but there are merge conflicts that need to be resolved before we can merge.

🔧 How to Fix:

Please update your branch with the latest master:

git checkout fix/issue-12
git fetch upstream
git rebase upstream/master
# Resolve conflicts in gui/comparison.py if any appear
git push --force-with-lease

Or using merge:

git checkout fix/issue-12
git merge upstream/master
# Resolve conflicts
git push

✅ After conflicts are resolved:

The PR looks great and is ready to merge! The changes are well-tested and properly implement the PSNR-B metric fix.

Let me know if you need any help resolving the conflicts! 🚀