Bug 691181 - File rendered incorrectly with -dGraphicsAlphaBits=4
Summary: File rendered incorrectly with -dGraphicsAlphaBits=4
Status: RESOLVED FIXED
Alias: None
Product: Ghostscript
Classification: Unclassified
Component: Graphics Library (show other bugs)
Version: 0.00
Hardware: All All
: P4 normal
Assignee: Michael Vrhel
URL:
Keywords:
Depends on:
Blocks: 690865
  Show dependency tree
 
Reported: 2010-03-17 15:52 UTC by Marcos H. Woehrmann
Modified: 2011-06-12 00:03 UTC (History)
1 user (show)

See Also:
Customer:
Word Size: ---


Attachments
scn-in-pattern.pdf (2.45 KB, application/pdf)
2010-03-17 15:52 UTC, Marcos H. Woehrmann
Details
screenshot.png (16.11 KB, image/png)
2010-03-17 15:52 UTC, Marcos H. Woehrmann
Details

Note You need to log in before you can comment on or make changes to this bug.
Description Marcos H. Woehrmann 2010-03-17 15:52:20 UTC
Created attachment 6070 [details]
scn-in-pattern.pdf

The attached file is rendered incorrectly with Ghostscript when specifying -dGraphicsAlphaBits=4 on the command line (I'm comparing the output to Adobe Acrobat 9.3.1, Apple Preview 5.0.1 (503), and Artifex Ghostscript).  See the attached screenshot.png for clarification.

The command line I'm using:

  bin/gs -sDEVICE=ppmraw -r300 -dGraphicsAlphaBits=4 -o test.ppm ./scn-in-pattern.pdf
Comment 1 Marcos H. Woehrmann 2010-03-17 15:52:38 UTC
Created attachment 6071 [details]
screenshot.png
Comment 2 Marcos H. Woehrmann 2010-03-17 15:55:44 UTC
Created attachment 6072 [details]
Bug690488.pdf

This file appears to have the sam problem.
Comment 3 Marcos H. Woehrmann 2010-03-17 17:51:09 UTC
Created attachment 6076 [details]
09_47N.PDF

Page 3 of this file also has a problem when converted with -dGraphicsAlphaBits=4 (though the symptoms are a bit different, so it may be an unrelated issue).
Comment 4 Ray Johnston 2010-03-18 17:10:00 UTC
Probably the pattern cache logic needs to handle alpha better. Might be related to other work by Michael to address patterns with transparency.
Comment 5 Michael Vrhel 2011-06-12 00:03:39 UTC
This appears to be fixed.  Likely from when I fixed the alpha bits to work with transparency.