Bug 691247

Summary:	jbig2dec doesn't handle halftone regions
Product:	jbig2dec	Reporter:	Ralph Giles <ralph.giles>
Component:	Missing Feature	Assignee:	Henry Stiles <henry.stiles>
Status:	RESOLVED FIXED
Severity:	normal	CC:	b.geisselmeier, christinedelight.top85, shailesh.mistry
Priority:	P4
Version:	master
Hardware:	PC
OS:	Linux
Customer:		Word Size:	---
Bug Depends on:
Bug Blocks:	691230

Description Ralph Giles 2010-04-16 06:08:59 UTC

The jbig2dec library doesn't have a decoder for halftone regions, and the two ubc testsuite files, amb_1.jb2 and abm_2.jb2 are not decoded correctly.

In both cases jbig2dec fails silently returning a blank (white) page. This is worse than failing with an error.

There is some code in jbig2_halftone.[ch] but it is incomplete. Gorac also contributed an implementation; see bug 690979 for Hin-Tak's factoring of that patch.

The library should be updated to handle halftone regions. For a long time this feature seemed to be unused in practice, but bug 691230 contains a wild file with a pattern region and corresponding dictionary.

Comment 1 Shailesh Mistry 2012-02-05 14:37:46 UTC

This bug has now been resolved by the fix in Bug691230 and can be closed down.