97931 - when displaying a stream of images mozilla shouldn't display them incrementally.

Status: RESOLVED WORKSFORME

(Core :: Graphics: ImageLib, defect)

Description

[wleese]

when opening a page that displays a stream of images it should not try to
display part of the image ASAP but instead it should wait till the entire image
has been downloaded.

to reproduce: go to any page with a webcam or one that displays a stream of
images.

result: when loading the next image in a stream it sometimes only shows half of
the next image and the other half of the old.

expected result: you should only see one image at a time (however long you have
to wait for the next.. or perhaps there shoulkd be some kind of delay for rare
occasions?)

i'm afraid i can't really give an URL 'cause the most cams are either porn,
personal, or ones with a very slow refresh time.

Comment 1

[David Hallowell]

Well pavlov did call the imagelib libpr0n so a porn webcam would be an ideal
test - I think as long as you warn about the content of a link then people won't
mind :)

But here's a non pornographic webcam link:
http://www.tynebridgewebcam.com/webcams.htm

Just click on one of those webcams and tell me if you see the problem there and
don't forget to tell us the build ID of mozilla (titlebar) as that may have a
bearing on things.
Also worth reading the Bug writing guidelines and the bugzilla helper, a link is
in the QA menu in mozilla to the writing guidelines. All bug reports are welcome
but ones following the guidelines are quicker to process.

Comment 2

[Christian Reis]

Reporter, could not verify with David´s suggestion. It would be best if you
provided a URL when the problem can be reproduced _and_ include a warning if
it´s pr0n. Thanks.

Comment 3

[wleese]

mm, all in best interest of mozilla's development..... (it actually concerned a 
personal webcam, which i certainly won't post here.).

http://www.ultrapasswords.com/club17/index.php

This btw is a java applet.

Perhaps the mungled images are because of slow painting on linux, or simply my 
low end machine at home: a pentium 60 with 96 RAM running debian unstable, 
XFree86 4.1. Netscape 4.x and Konqueror display it fine, Opera on the other 
hand has the same 'problem' as Mozilla.

David, the webcams you posted don't refresh quick enough to show the problem. 
Only with cams that have the appearance of a low quality video stream this 
problem occurs.

Comment 4

[David Hallowell]

Definitely must just be a low end machine problem, it works fine for me (900MHz
Athlon). Dunno about Konqueror but Netscape 4.x uses its own built in JVM and
Mozilla uses the sun Java plugin which is what Opera uses too.

Unless you can reproduce this bug with a webcam that streams images (like the
rather boring link I sent but with a higher refresh rate) then this is a bug
with suns JVM and not Mozilla.

Comment 5

[wleese]

Far reasoning. Konqueror uses (in my case) Blackdown I believe.

Testing with Galeon doesn't show any problems (although it remains noticably
slower than Netscape 4.x). So apparently it's speed related.

BTW, shouldn't Mozilla's JVM be much faster in general than Netscape's?
Anyway, not sure what to do with this bug because the problem could lie just
about anywhere.. is there any code that prevents streamed images being
incrementally displayed if the entire image 'doesnt arrive in time'?

Comment 6

[Keyser Sose]

Marking these all WORKSFORME sorry about lack of response but were very
overloaded here. Only reopen the bug if you can reproduce with the following steps:

1) Download the latest nightly (or 0.9.6 which should be out RSN)
2) Create a new profile
3) test the bug again

If it still occurs go ahead and reopen the bug. Again sorry about no response
were quite overloaded here and understaffed.

Comment 7

[Grey Hodge (jX)]

Accidentally marked, reopening.

Comment 8

[alge]

This
1) works for me (and made me slightly sick so I probably won't get any sleep
tonight)
2) is wrong component, as the java plugin does not use imagelib
3) has a misleading summary
4) You can't expect a pentium 60 to play nice with suns JVM and pr0n sites.
.. and anyway, a "stream" should always display images as fast as they are sent
from the server. see a streaming tutorial or something.

feel free to reopen if you've got any other testcases which actually fit the bug
description (as in: no plugins..)