Rolling Shutter Camera Synchronization with Sub-millisecond Accuracy

Posted on Út 20 prosinec 2016 in misc • Tagged with publication

A simple method for synchronization of video streams with a precision better than one millisecond is proposed. The method is applicable to any number of rolling shutter cameras and when a few photographic flashes or other abrupt lighting changes are present in the video. The approach exploits the rolling shutter sensor property that every sensor row starts its exposure with a small delay after the onset of the previous row. The cameras may have different frame rates and resolutions, and need not have overlapping fields of view. The method was validated on five minutes of four streams from an ice hockey match. The found transformation maps events visible in all cameras to a reference time with a standard deviation of the temporal error in the range of 0.3 to 0.5 milliseconds. The quality of the synchronization is demonstrated on temporally and spatially overlapping images of a fast moving puck observed in two cameras.

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Image Ground Truth GUI Tools

Posted on St 11 září 2013 in misc • Tagged with python

Evaluation of computer vision algorithms usually requires comparison against manually created ground truth. Following two GUI tools are easy to use for a basic annotation in images. Both are written in Python and should be easy to modify.

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Python Packages for Graph Cuts on Images

Posted on Út 23 červenec 2013 in misc • Tagged with python

Review of python packages for performing graph cuts on images.

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