SIGSEGV on tags appearing in frame

[racamirko]

I'm getting sigsegv on tags appearing in ReadBits::run(), line 95. It appears with one and with more tags in input.

System: Ubuntu 13.10 x64, OpenCV 2.4.5 chilitags compiled with debug flags, but the problem originally occurred without them.

[racamirko]

Just to clear up "tags appearing" = tag is touching the edge of the border of the frame and/or is partially outside the frame.

[racamirko]

And more data... it seems that the tTransformedSamplePoint on sigsegv has a negative coordinate (i.e. y = -1172.18066 )

[racamirko]

Temporary solution:

cv::Rect tImageArea = cv::Rect(cv::Point(0,0), cv::Size(tInputRoi.cols, tInputRoi.rows));
    for (auto& tTransformedSamplePoint : tTransformedSamplePoints) {
        if( tImageArea.contains(tTransformedSamplePoint)  )
            *tSampleData++ = tInputRoi.at(tTransformedSamplePoint);
        else
            *tSampleData++ = 0; // dummy data
    }

[qbonnard]

A wild user appears! User uses bug report! It's very effective!

It looks like one of the bugs that are fixed in the neverending refactoring, e.g. this one or maybe this one.

Sorry that the refactoring takes so long, I blame the Christmas break. How urgent is it to fix the bug ? Can it wait the merge of the refactoring (hopefully next week), or do you want me to bring the fixes to the master branch ?

FYI: the negative coordinates usually happen when the detected quadrilateral is concave, which does not suit well the perspective deformation estimation... Most likely, the concave quadrilateral is just noise anyway, so your fix should not create false negatives.

[severin-lemaignan]

@racamirko Would it be possible to provide an image that triggers the bug? or is it +- random?

[racamirko]

@severin-lemaignan It's random (I'm using camera for samples). @qbonnard I switched to the big-refactoring branch and I'll continue from there. I'll report if I run into any more problems, or close the bug if it doesn't appear :)

[severin-lemaignan]

@racamirko Did you run again into the bug, or can we close the issue?

[racamirko]

@severin-lemaignan Sorry, forgot about it. I haven't used it in a while (other tasks).

[severin-lemaignan]

Fine. Feel free to re-open if the bug reappears.