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<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - cairo_surface_create_similar_clip can create negative surfaces"
href="https://bugs.freedesktop.org/show_bug.cgi?id=70671">70671</a>
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<th>Assignee</th>
<td>poppler-bugs@lists.freedesktop.org
</td>
</tr>
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<th>Summary</th>
<td>cairo_surface_create_similar_clip can create negative surfaces
</td>
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<th>Severity</th>
<td>major
</td>
</tr>
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<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux (All)
</td>
</tr>
<tr>
<th>Reporter</th>
<td>michael@cadilhac.name
</td>
</tr>
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<th>Hardware</th>
<td>x86 (IA32)
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Version</th>
<td>unspecified
</td>
</tr>
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<th>Component</th>
<td>cairo backend
</td>
</tr>
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<th>Product</th>
<td>poppler
</td>
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<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=87877" name="attach_87877" title="This PDF triggers a cairo error">attachment 87877</a> <a href="attachment.cgi?id=87877&action=edit" title="This PDF triggers a cairo error">[details]</a></span>
This PDF triggers a cairo error
The attached PDF is a single page containing an XObject which prints a Knockout
transparency group, which itself prints a non-Knockout transparency group. It
is not properly drawn using evince because of a cairo error.
In greater details:
With this PDF, in cairo_surface_create_similar_clip, the surface resulting
from:
result = cairo_surface_create_similar (target, content, width, height);
is defined with a negative height. This in turn leads to the following Cairo
error when drawing the group:
BAD status: invalid value (typically too big) for the size of the input
(surface, pattern, etc.)
I'm not sure what the comment:
//XXX: negative matrix
in the body of the function is refering to, but indeed, there's a sign problem.
Adding abs(...) around the two substractions (CairoOutputDev.cc:1425 and next)
does the trick --- the PDF is rendered correctly ---, but I'm not sure this is
the right fix.
(Using git poppler)</pre>
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