339673 - png image not correctly rendered at small scale (~ 7%)

Status: RESOLVED INCOMPLETE

(Core Graveyard :: Image: Painting, defect)

Description

[Pierre]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; fr; rv:1.8.0.3) Gecko/20060426 Firefox/1.5.0.3
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; fr; rv:1.8.0.3) Gecko/20060426 Firefox/1.5.0.3

This page display a resized png image (https://www.rhapso.com/temp/img1.png) containing a border.
It is correctly displayed with Firefox under GNU/Linux, but not under Microsoft Windows : the border disappears.


Reproducible: Always

Comment 1

[penagate]

WFM as far as I know. Can you attach a screenie of how you see it under Windows.

Comment 2

[Ryan Jones-Ward [:sciguyryan]]

WFM

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060527 Minefield/3.0a1 - Build ID: 2006052802

Comment 3

[Régis Caspar]

If I compare URL and (https://www.rhapso.com/temp/img1.png), the resized image is missing a black border on left/bottom here.

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060529 Minefield/3.0a1 ID:2006052910 [cairo]

Comment 4

[Régis Caspar]

Attachment: Interactive testcase

A testcase derivated from the URL provided by the reporter.

Comment 5

[Steve England [:stevee]]

Reporter, do you still see this problem with the latest Firefox 2? If not, can you please close this bug as WORKSFORME. Thanks!

Comment 6

[Wayne Mery (:wsmwk)]

behavior in windows FF2 and trunk 2007092705 is no borders until 7%. 7% has no border (white) on the top. I don't know about linux. 

And no one has commented about MAC - perhaps Jo can?

Comment 7

[Jo Hermans]

On Mac OS X with Firefox 2.0.0.8pre (I can't run the trunk anymore, my hardware is too old), I could see the white and black borders all the way to 1% - it doesn't have the bug.

Comment 8

[Wayne Mery (:wsmwk)]

linux ... anyone see this on?

Comment 9

[Wayne Mery (:wsmwk)]

confirming - I couldn't find any dupes and comment 0 mentions WFM on linux, so windows only

Comment 10

[Wayne Mery (:wsmwk)]

on my display the left and top border differ in width at the points: from 19 to 21 (then matching at 22), again 31 to 35, 43-49, etc.  Perhaps related to the aspect ratio of the display?  Mine is a 23" _wide_ screen. (I don't have any squarish screens to test)

searching further ... there's plenty of div bugs (about half unconfirmed) - hard to tell what might be related to this. 

Comment 11

[Régis Caspar]

Wayne, I don't understand where do you see a div issue? This bug is related to image resizing.

=> Core / Image GFX, summary update

Comment 12

[dolphinling]

I see no border at 5% on trunk linux. However, I'm not sure this is a bug. The image's border is 7px wide. At 5%, only one out of 20 pixels would be displayed. Even with whatever averaging we do, that's going to be hard to see. And the GIMP, I notice, stops displaying the borders at 12.5%. So I think we're not doing anything wrong here.

Comment 13

[Wayne Mery (:wsmwk)]

(In reply to comment #11)
> Wayne, I don't understand where do you see a div issue? This bug is related to
> image resizing.

yes, quite right.  _After_ i clicked commit, it didn't make sense to me either.


(In reply to comment #12)
> I see no border at 5% on trunk linux. However, I'm not sure this is a bug. The
> image's border is 7px wide. At 5%, only one out of 20 pixels would be
> displayed. Even with whatever averaging we do, that's going to be hard to see.
> And the GIMP, I notice, stops displaying the borders at 12.5%. So I think we're
> not doing anything wrong here.

I can't speak to the original report, but:
1. comment 10 - left and top border width should be the same, not 1px dif, no?
2. why your results differ from Jo's - screen resolution?

Comment 14

[Pierre]

On my GNU/Linux system, everything is ok with Firefox 2 (Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.8) Gecko/20070914 Mandriva/2.0.0.8-1mdv2008.0 (2008.0) Firefox/2.0.0.8)
I have the 4 borders till 1%.
But on my Microsoft Windows 2000 system it is only ok till 8%.
at 7% the top border disappears, and at 6% all disappear, no more borders.
It is a standard Firefox 2 (Mozilla/5.0 (Windows; U; Windows NT 5.0; fr; rv:1.8.1.9) Gecko/20071025 Firefox/2.0.0.9)
Same thing on Windows XP.