Hi,

FilterEngine::apply() does not take into account the srcRoi.x parameter:
As one may notice in the documentation, the code is bugged:
http://docs.opencv.org/modules/imgproc/doc/filtering.html#FilterEngine

<pre>
proceed( src.data + y*src.step,
(int)src.step, endY - startY,
dst.data + dstOfs.y*dst.step +
dstOfs.x*dst.elemSize(), (int)dst.step );
</pre>

should be replaced by

<pre>
proceed( src.data + y*src.step + _srcRoi.x*src.elemSize(),
(int)src.step, endY - startY,
dst.data + dstOfs.y*dst.step +
dstOfs.x*dst.elemSize(), (int)dst.step );

</pre>
Cheers,
Th