[#4234] - JImage: drop incorrect use of imagecopyresize (take 2)
- Closed
- 8 May 2016
- Medium
- Build: staging
- # 4234
- Diff
- piotr-cz:patch_JImage2
- Success continuous-integration/travis-ci The Travis CI build passed Details
- Failure JTracker/HumanTestResults Human Test Results: 0 Successful 2 Failed. Details
User tests: Successful: Unsuccessful:
Rebased to staging branch #2116
Description from #2116 (added by @zero-24)
There was a invisible bug in the resize method that showed up when I've implemented SCALE_FIT functionality - I didn't have time to update last commit like in the Framework, which is attached here. Below is explanation what it's all about.
The class didn't evaluate loaded image be transparent (see fix) and thus was always using imagecopyresampled function and everything seemed alright.
After the patch resource handle is evaluated to be transparent and imagecopyresized method produces visually poor results.
After little research I'm not sure, why it's even been used; I hope the author @rvsjoen can say something about it.
It seems that imagecopyresized is quite faster, but still would be used for wrong reasons.
Other frameworks:
-
Lavarell Resizer bundle uses just
imagecopyresampled - Symfony too
- Kohana as well
Resources:
- TuxRadar: Scaling and rotating
- StackOverflow: php imagecopyresized vs imagecopyresampled
- php.blogle.info: Performance comparison
- random search result showing difference in quality
jissues-bot
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zero-24
- | Category | ⇒ | Libraries |
Updated again.
How to test? thanks
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I have tested this item 
unsuccessfully on eac76a4
I was able the reproduce the "visually poor result" before the patch, but the patch itself didn't work either, because the transparency got lost. I'll attach the 2 images that have been generated in the next comment.
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I have tested this item unsuccessfully on eac76a4
Picture is no more transparent. the Problem is with and without the patch the same Problem
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Original:
https://commons.wikimedia.org/wiki/File:Tibia_insulaechorab_transparent.png
Before:
After:
Tested on 3.4.5 with PHP 5.4.38.
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I tested under PHP Version 5.6.8
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Hello @piotr-cz
Thank you for your contribution.
The last comment here was on 24th October 2015. So the question is, Is this issue/pull request still valid?
If no reply is received within 4 weeks we will close this issue.
Thanks for understanding!
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Hi this fix is actually from 2013 and I'm not using this Joomla functionality anymore.
As there are two failed tests it looks like this PR doesn't address the problem.
Anyway let's wait suggested 4 weeks before closing it.
There really is no point in waiting. If you're not going to look at the issue to see why your own PR has two failed tests it might as well be closed right now
Thank you for your suggestion but it has been decided that this is not something that will be included in the core of Joomla!.
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| Status | Pending | ⇒ | Closed |
| Closed_Date | 0000-00-00 00:00:00 | ⇒ | 2016-05-08 14:29:29 |
| Closed_By | ⇒ | Kubik-Rubik |
I have tried with png transparent images with this fix it works, can-you fix conflicts in the PR ?