OpenCap pipeline locally

[Scott Uhlrich]

This is most likely an issue with camera calibration parameters (intrinsics or extrinsics). Make sure the camera model you are using (i.e., the intrinsic/extrinsic parameters in the mathematical camera model) matches what is used in the code base. The distortion parameters are a likely culprit here.

[Carlos Gonçalves]

Thanks a lot Scott,

As I mentioned, I collected gait data with OpenCap online, downloaded the files, and tried running everything locally. I'm using the already used (online) calibration file "cameraIntrinsicsExtrinsics.pickle".

So, do you have any guess where to change the camera model in the available code?

I'm doing my tests making changes to the main.py file in opencap-core directory.

Best regards.

[Carlos Gonçalves]

About the camera model, I'm using the same metadata file from the OpenCap session.

So it is iPhone14,7 for this data.

Is that it?

Printing CamParamDict I think is right. The inial values are the same, the last ones are different (I suppose this first ones are intrinsic values):

Code: Select all

{'Cam0': {'distortion': array([[ 1.33330036e-01, -4.24884275e-01, -4.19435795e-04,
         7.74451704e-05,  4.77849416e-01]]), 'intrinsicMat': array([[917.37931162,   0.        , 360.43991397],
       [  0.        , 917.79164758, 636.84639784],
       [  0.        ,   0.        ,   1.        ]]), 'imageSize': array([[1280.],
       [ 720.]]), 'rotation': array([[-0.8987816 , -0.03383321,  0.43708917],
       [ 0.01267564, -0.99860628, -0.05123309],
       [ 0.43821337, -0.04050698,  0.89795781]]), 'translation': array([[ 121.41596193],
       [1019.86963964],
       [2891.45558384]]), 'rotation_EulerAngles': array([[ 0.70043917],
       [-0.07341272],
       [ 3.03713135]])}, 'Cam1': {'distortion': array([[ 1.33330036e-01, -4.24884275e-01, -4.19435795e-04,
         7.74451704e-05,  4.77849416e-01]]), 'intrinsicMat': array([[917.37931162,   0.        , 360.43991397],
       [  0.        , 917.79164758, 636.84639784],
       [  0.        ,   0.        ,   1.        ]]), 'imageSize': array([[1280.],
       [ 720.]]), 'rotation': array([[-9.06270219e-01, -8.72180304e-04, -4.22697917e-01],
       [ 2.11763384e-02, -9.98835865e-01, -4.33414009e-02],
       [-4.22168038e-01, -4.82302150e-02,  9.05233668e-01]]), 'translation': array([[ 241.63476081],
       [1056.79149861],
       [2964.82450638]]), 'rotation_EulerAngles': array([[-0.67743632],
       [-0.07342459],
       [ 3.05523322]])}}

[Carlos Gonçalves]

Update!

I tried with another video, and it worked!

I still need to figure out why, but the intrinsic and extrinsic configurations are ok for all trials.

I hope I can get back here with the augmented TRC file.

Best regards.