534692 - Firefox 'posterizes' SOME photos...whereas Internet explorer DOES NOT.

Status: RESOLVED INCOMPLETE

(Core :: Graphics, defect)

Description

[tommylee1023]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.5) Gecko/20091102 Firefox/3.5.5
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.5) Gecko/20091102 Firefox/3.5.5

at http://www.pbase.com/tommylee1023/image/120286190
you can see this photo posterized whereas the internet explorer viewing of this file DOES NOT

I screen captured the example  in Firefox and Internet explorer  
see this address for the two captured examples...
http://www.pbase.com/tommylee1023/tweet



Reproducible: Always

Steps to Reproduce:
1.go to http://www.pbase.com/tommylee1023/tweet ... for the examples
2.view (with firefox) the first two birds - nearly identical shots but only ONE posterizes
3.look at the same page /pics with internet explorer
4. look at the two screen capture examples
5. all add-ins were disabled
Actual Results:  
reproduced the issue

Expected Results:  
reproduced results

I first saw these posterizations on SOME of my files... in the skies of photos...which I immediately thought was due to reducing number of colors or compre43ssion...
...but on SOME FILES?

I THOUGHT at first that PBASE was compressing SOME FILES..they said NO...
then I tried I.E.  and saw the difference..

only on some files.. the two photos are a few seconds apart...
but MAYBE one has some threshold of noise?... that firefox struggles with?
just trying to guess the issue
not happening in  I.E.

if this is some 'quality' issue with firefox...then it needs fixin..
if it is with ME...then please explain..
thanks for the help
and I am available to respond if you need more help...

Comment 1

[Ria Klaassen (not reading all bugmail)]

Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.7pre) Gecko/20091208 Shiretoko/3.5.7pre

I see no posterization.

Comment 2

[tommylee1023]

can you view the photos in I.E. versus Firefox ..?

there is likely a reduction in # of colors...or a similar sort of effect..
you have to compare the same picture ...back and forth .. in the two browsers..

clearly firefox is handling this differently....inferior treatment of gradual color changes...
this following shot...to the left of the bird's head.. the shadow..
is handled smoothly in I.E.  but not in firefox
http://www.pbase.com/tommylee1023/image/112599382

seems to occur on shots where there is a noise gradient.. which would be made smoother with more colors....finer gradient of color changes..

you need to use both browsers to see the poorer, but subtle handling.

if it is not seen ...what next?

Tom Schmid
dec 16, 2009

Comment 3

[Ria Klaassen (not reading all bugmail)]

On my computer I see no difference.

Comment 4

[RNicoletto]

Attachment: Firefox 3.6.x - IE7 comparison on Windows XP

I can't see any difference between Firefox 3.6.x and IE7. I can't see any "posterize" effect as well.

Comment 5

[Gregory Pappas [:gregp]]

Test case 404s and no archive can be located.