192068 - Mozilla claims it can't display some greyscale JNGs because they contain errors

Status: VERIFIED DUPLICATE of bug 181676

(Core :: Graphics: ImageLib, defect)

Description

[Greg K.]

Both FizzillaMach/2003020303 and Win/2003010408 claim to not be able to display
the JNG image, <http://greg.tcp.com/Graphics/Desert,%20larger.jng>, because,
they claim, it contains errors.

The JNG image was converted from a greyscale PNG
(<http://greg.tcp.com/Graphics/Desert,%20larger.png>) with alpha channel using
the Unix application ImageMagick 5.5.4. If the allegedly erroneous JNG is
reconverted to PNG using ImageMagick, Mozilla displays the resulting PNG just fine.

Mozilla displays color JNGs created by ImageMagick just fine, such as
<http://greg.tcp.com/Graphics/Washu.jng>.

Mozilla also displays a smaller version of the grey JNG fine
(<http://greg.tcp.com/Graphics/Desert,%20translucent,%2064px.jng>), as well as
another example grey JNG (<http://www.libmng.com/JNGsuite/tyson_large_g_img.html>).

The Windows application Futuris Imager successfully displays the allegedly
erroneous JNG image.

Comment 1

[Greg K.]

Reassigning to [e-mail] on suggestion of biesi in #mozillazine.

Comment 2

[Greg K.]

The File Insider analysis tool at <http://www.file-insider.com/> seems to claim
the allegedly erroneous JNG file is, in fact, okay.

Comment 3

[Greg K.]

Attachment: Testcase with OBJECT referencing test JNG URL (see comment 3)

Note also that if the JNG URL is referenced in an OBJECT, Mozilla will crash at
memmove after shift-reloading such a testcase no more than twice.

Comment 4

[Greg K.]

Attachment: Crash report generated by FizzillaMach/2003020303 showing crash at memmove after shift-reloading attachment 113649 (see comment 4)

Comment 5

[Christian :Biesinger (don't email me, ping me on IRC)]

ok, the problem is this:
This codepath is reached:
http://lxr.mozilla.org/seamonkey/source/modules/libpr0n/decoders/mng/imgContainerMNG.cpp#581

At that point, ret is 1027, which means that the CRC Check failed, see
http://lxr.mozilla.org/seamonkey/source/modules/libimg/mng/libmng.h#2097

therefore, looks like a libmng problem to me.

Comment 6

[Christian :Biesinger (don't email me, ping me on IRC)]

oh, and note that my testing is with libmng 1.0.4, as I'm using the system MNG
library.

I'll try 1.0.5rc3 now.

Comment 7

[Christian :Biesinger (don't email me, ping me on IRC)]

This is fixed in libmng 1.0.5rc3.

Therefore, marking as duplicate of bug 181676



*** This bug has been marked as a duplicate of 181676 ***

Comment 8

[Greg K.]

Thanks, biesi.

Comment 9

[Greg K.]

Is that also what caused the crash I mentioned?

Comment 10

[Christian :Biesinger (don't email me, ping me on IRC)]

Hm, don't know, I can't reproduce the crash in Linux nightly build 2003020508
I loaded the "testcase" attachment here and hit shift+reload several times. no
crash. maybe mac specific?

Comment 11

[Greg K.]

I have filed related bug 192204 (OBJECT nesting not being respected after
ImageLib failure) and bug 192205 (the crash mentioned in comment 3).

Comment 12

[:deanis74]

v