Question about recording time

[Wisavaporn Niamsang]

Hi,
For collecting and analyzing data on human gait and movement, OpenCap is incredibly useful, which is why I truly appreciate it. As a part of my research, I am interested and have taken OpenCap. However, I have a question. I would like to know that when I record data and I use the farm rate at 120fps then I try to record the data for around 10-20 seconds. But the data that I got after that is just 3-4 seconds. I'm not sure how it happened and how can I solve that problem.

Thank you

[Antoine Falisse]

Hi,
The data is trimmed if the person is not visible by at least two cameras in the beginning and end of the trial.
Best,
Antoine

[Wisavaporn Niamsang]

Thank you for your good answer.

I'm pretty sure both cameras can see and capture the whole body of a patient at the beginning and end of the trial. But I'm not sure if it might have something wrong to do with my patients who use prosthetics during the data collection process.

Thank you very much

[Scott Uhlrich]

If at least 2 cameras cannot see all keypoints on the person, it will assume they have left the frame and trim the trial. If this problem is showing up with prosthesis users, my guess is that the pose detection algorithm is not recognizing some of the joints on the prosthesis. The more like a biological limb you can make it look (eg wearing pants), the better the pose estimatoin model will likely do.