When the spherical images uploaded by mapillary to openstreetmap, it attaches fields to the images like computed_rotation, computed_altitude, computed_camera. In documentation, its mentioned that computed_rotation is in rotation vector in axis-angle representation.I want to know how computed_rotation is being calculated.
Data present in GoPro image
'GRAV': '-0.4097, 0.9118, -0.0274',
'IORI': '1.0000, 0.0000, 0.0000, 0.0000',
'CORI': '0.3888, -0.0908, 0.8825, 0.2483',
'SHFX': '0.7278',
'SHFY': '1.9069',
'SHFZ': '2.0786',
'ANGX': '5.6211',
'ANGY': '7.2492',
'ANGZ': '19.3791',
Explanation of the keys which I found in GoPro GPMF Parser
| FourCC | Property | approximate frequency (Hz) | SIUN or UNIT | Comment |
|---|---|---|---|---|
| CORI | Camera ORIentation | frame rate | n/a | Quaternions for the camera orientation since capture start |
| IORI | Image ORIentation | frame rate | n/a | Quaternions for the image orientation relative to the camera body |
| GRAV | GRAvity Vector | frame rate | n/a | Vector for the direction for gravity |
I tried with the camera orientation data which is present in GoPro images in quaternion representation and converting it to rotation vector, but the values are not matching up with the openSFM values