Conversion from 3-D to 2-D annotations results in empty annotation files

[kkannan8291]

@mpitropov I using the script 'cadc_unpack_all_kitti.py' in order to convert the 3-D annotations to 2-D annotations and make it compliant similar to the Kitti dataset. While this seems to work for 55% of the CADC dataset, the 2-D annotations (.txt files generated) are empty for the remaining images. I am seeing this issue across all cameras. While the number of images without annotations are less than 50 for Cam00, 01 and 07, the other cameras have over 50% of the dataset without any labels. Especially for Cam04, the entire dataset has no annotations.

On closer introspection into the 3-D annotations.json file, I noticed that the 'camera used' parameter is set to 'null' for over 90% of the dataset (Let's take scenario 2 [2018_03_06] as an example). Out of the 5185 usages of 'camera_used', 4398 of them are set to 'null'. Can you please explain what this exactly means?

Do you think this could be the root cause for the empty 2-D annotation files that are being generated?

reference: https://github.com/mathild7/faster_rcnn_pytorch_multimodal/blob/3145d91cba5ec38769b76af8f6e118748876c280/tools/cadc_unpack_all_kitti.py

[mpitropov]

Scale AI were the ones who labelled the dataset and the camera used parameter is filled in if they used the camera during labelling. I think it will be null if they didn't use the camera images and only relied on lidar.

There is also an updated converter script in this issue you can try #21