489342 - Artifacts in some APNG frames

Status: RESOLVED WORKSFORME

(Core :: Graphics: ImageLib, defect)

Description

[Andrew Smith]

Attachment: image to view to see the problem

I've got an email saying:

"Looks like that APNG bug has returned in 3.0.7 ...  Haven't tried 3.0.8 yet.
https://bugzilla.mozilla.org/show_bug.cgi?id=420416

And I've got one more sample. Most likely the same bug."

From the same guy who reported bug 420416. Attachment is attached.

Will try to get more information from the reporter. I haven't reproduced it myself (am on 3.0.5 on Linux).

Joe, do you want this one?

Comment 1

[Ryan VanderMeulen [:RyanVM]]

Reproducible in 3.1b3 as well.

Comment 2

[Andrew Smith]

More info from the reporter
---------------------------

> Did you get a chance to try 3.0.8?

Yes, and I tried 3.0.9 too. Both buggy. It started with 3.0.7:

3.0.6 - ok
3.0.7 - buggy
3.0.8 - buggy
3.0.9 - buggy

> > I take it you're seing it on Windows?

Yes.

> > 

Also, that old image is in litmus test:
https://litmus.mozilla.org/show_test.cgi?id=5213

> > I hope to add more details from you and trying it myself (I'm on linux).

I remember that Glenn fixed it the last time by crearing prev_row
buffer before decoding the next frame.

I recently ran into the very similar looking problem in my little app
and also fixed it by clearing prev_row buffer.

Comment 3

[Glenn Randers-Pehrson]

This works for me now, apparently fixed by the check-in of libpng-1.2.40 (bug #504805)

Comment 4

[Glenn Randers-Pehrson]

Artifacts are still present in Firefox 3.6.16

Comment 5

[Glenn Randers-Pehrson]

Works for me with the current nightly and with Firefox 24.0