Have you tried to covert the video clip into a different video format? Video formats and codecs are constantly evolving and a video clip converter is an essential tool when doing video analysis. The OSP-Tracker team has had good luck using online cloudconvert software.
https://cloudconvert.com/mp4-converter
The mp4 with H264 codec should work with both Java and JavaScript versions of Tracker.
For unsupported videos or videos with a non-constant framerate, we now recommend converting them to mp4 using the open source application HandBrake, available for Windows, Linux and MacOS platforms at https://handbrake.fr/. Choose the default "Fast 1080p30" preset, then in the Video tab choose "Constant Framerate".
