[question] SelectiveSearchSegmentationStrategySizeImpl does not merge sizes?

[vadimkantorov]

https://github.com/opencv/opencv_contrib/blob/master/modules/ximgproc/src/selectivesearchsegmentation.cpp#L383-L385:

void SelectiveSearchSegmentationStrategySizeImpl::merge(int /* r1 */, int /* r2 */) {
                // Nothing to do (sizes are merged at parent level)
            }

but I could not find where it is done at parent level. Parent level seems to define merge() method as empty. Is it a bug or am I missing anything? Thank you!

[vadimkantorov]

Does this comment refer to size updates made in hierarchicalGrouping https://github.com/opencv/opencv_contrib/blob/master/modules/ximgproc/src/selectivesearchsegmentation.cpp#L1038 ?

If so, could a comment be added on why the sizes are handled in different places than all other features like histograms?

Thanks!

[vadimkantorov]

Why are start_x / start_y recomputed twice? https://github.com/opencv/opencv_contrib/blob/master/modules/ximgproc/src/selectivesearchsegmentation.cpp#L584 the computation uses bbox which isn't modified after initialisation

[alalek]

BTW, You may use git "blame" to determine author of that code and use @ mention.

related PR: #520

[vadimkantorov]

cc @the-glu

[the-glu]

I have no idea, sorry :/

This is old code and I'm not working with opencv since too much time..

[vadimkantorov]

I understand :(

One more question if you may remember: H component in HSV is from 0 to 360 in OpenCV, not from 0 to 1, and no normalization seems to be done. Is it intentional?

[the-glu]

No exact idea, but since it's the Hue does it really make sense to normalize it ?