597959 - Firefox can't handle JPEG images with quantization tables other than 8x8

Status: RESOLVED WONTFIX

(Core :: Graphics: ImageLib, defect)

Description

[Peter Jeremy]

User-Agent:       Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.9.1.12) Gecko/20100912 Firefox/3.5.12
Build Identifier: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.9.1.12) Gecko/20100912 Firefox/3.5.12

The image at the above URL does not display and Tools -> Page Info reports that it is 0px x 0px.  This is due to a bug in the IJG jpeg-6b code embedded in Firefox. The problem has been verified to still exist in 3.5.13, 3.6.10 and 4.0beta5.

The original JPEG spec appears to have specified that the quantization table should be 8x8 but I gather it now allows any square table between 2x2 and 8x8.  The IJG jpeg-6b code only supports 8x8 tables (and ignores the "length" of the DQT block, reading a multiple of 8x8 table entries).  In the image above, the SOF block is close to the DQT block and is eaten by the code that processes the DQT block, leaving the image size initialised to 0x0.

This problem does not exist with the IJG jpeg-8b code and I suggest that the Mozilla project consider upgrading to a recent jpeg.

Reproducible: Always

Steps to Reproduce:
1. Attempt to view above URL

Actual Results:  
Browser will just display the URL in the window.

Expected Results:  
Display actual image.

Comment 1

[Gordon P. Hemsley [:GPHemsley]]

I'm gonna go ahead and confirm this, because I get "this image cannot be displayed because it contains errors" on Firefox 5 Beta.

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:5.0) Gecko/20100101 Firefox/5.0

Comment 2

[Jeff Muizelaar [:jrmuizel]]

I believe that these images produced by IJG jpeg-8b are no longer compliant with the JPEG spec. I don't think we have any intention of supporting the extensions added to IJG jpeg-8.