Bug 74883 - blend usage in PDF with spot colors casue random output under windows
Summary: blend usage in PDF with spot colors casue random output under windows
Status: RESOLVED FIXED
Alias: None
Product: poppler
Classification: Unclassified
Component: splash backend (show other bugs)
Version: unspecified
Hardware: All Windows (All)
: medium normal
Assignee: poppler-bugs
QA Contact:
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-02-12 10:21 UTC by Thomas Freitag
Modified: 2014-02-12 20:51 UTC (History)
0 users

See Also:
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Attachments
PDF shows the bug (248.62 KB, application/pdf)
2014-02-12 10:21 UTC, Thomas Freitag 		Details
output when splashModeDeviceN8 is used (242.39 KB, image/jpeg)
2014-02-12 10:23 UTC, Thomas Freitag 		Details
Patch which solves the problem (495 bytes, patch)
2014-02-12 10:28 UTC, Thomas Freitag 		Details | Splinter Review
Output after applying the patch (70.61 KB, image/jpeg)
2014-02-12 10:30 UTC, Thomas Freitag 		Details
View All

Description Thomas Freitag 2014-02-12 10:21:01 UTC 
Created attachment 93923 [details]
PDF shows the bug

When blend functions are used in PDF with spot colors (separation colorspace) in splash backend in splashModeDeviceN8 mode, the output shows random colors when used under windows (at least VisualC compiled)
Comment 1 Thomas Freitag 2014-02-12 10:23:19 UTC 
Created attachment 93924 [details]
output when splashModeDeviceN8 is used
Comment 2 Thomas Freitag 2014-02-12 10:28:35 UTC 
Created attachment 93926 [details] [review]
Patch which solves the problem

The reason for the random colors is the uninitialized local variable cBlend. The blend functions only fills offset 0 to 3, so offset 4 up to 4 + SPOT_NCOMPS are left uninitialized, but all offsets are stored in the bitmap.
So we need to initialize these offsets with 0!
Comment 3 Thomas Freitag 2014-02-12 10:30:02 UTC 
Created attachment 93927 [details]
Output after applying the patch
Comment 4 Albert Astals Cid 2014-02-12 20:51:22 UTC 
Pushed

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