Where are the hooks among classes?

[algoteam5]

In your config file for train 65, I can see a class order like this:
ZeroShotMaskRCNN -> BackgroundAwareRPNHead -> SharedFCSemanticBBoxHead - > SemanticFCNMaskHead

They are classes located in mmdet/models, where are the hook functions that connect among those classes?

[zhengye1995]

See this code, the mmcv runner hooks all these components.

[algoteam5]

So they are processed in order right? and what if I just want to run ZeroShotTwoStageDetector only? how would I change?

[zhengye1995]

In fact, ZeroShotTwoStageDetector is composed of Backbone, BackgroundAwareRPNHead, SharedFCSemanticBBoxHead and SemanticFCNMaskHead. Just like mask rcnn is also composed of similar modules.

[algoteam5]

"In fact, ZeroShotTwoStageDetector is composed of Backbone, BackgroundAwareRPNHead, SharedFCSemanticBBoxHead and SemanticFCNMaskHead."
I checked the zero_shot_two_stage.py file and I didn't see where did you call these functions BackgroundAwareRPNHead, SharedFCSemanticBBoxHead.

[zhengye1995]

"In fact, ZeroShotTwoStageDetector is composed of Backbone, BackgroundAwareRPNHead, SharedFCSemanticBBoxHead and SemanticFCNMaskHead."
I checked the zero_shot_two_stage.py file and I didn't see where did you call these functions BackgroundAwareRPNHead, SharedFCSemanticBBoxHead.

Please See:
In zero_shot_two_stage:

1. BackgroundAwareRPNHead: Instantiate,Forward

2. SharedFCSemanticBBoxHead: Instantiate,Forward

3. SemanticFCNMaskHead: Instantiate,Forward

[algoteam5]

Oh we don't need to directly call BackgroundAwareRPNHead, SharedFCSemanticBBoxHead? How does builder know we wanted to call BackgroundAwareRPNHead and SharedFCSemanticBBoxHead from Registry?

[zhengye1995]

Yes, we don't need to directly call BackgroundAwareRPNHead, SharedFCSemanticBBoxHead. We pass the class name and the corresponding parameters from config file into zero_shot_two_stage, the the builder uses the class name like BackgroundAwareRPNHead to build it, see the build code here.

[algoteam5]

You're awesome. I've got it. I was looking at the registry.py and was wondering that what is shared_head and how is it different from head?

[zhengye1995]

shared_head is a share head which is shared between bbox_head for detection and mask_head for instance segmentation.