Obtain Query POS Embeddings in Semantically Aligner

[jiaozhiqiang]

Thank you very much for your contribution!
I want to know why the Query POS Embedding in Semantically Aligner has the operation of "*0.5" before it passes through Sin POS Embedding.

SAM-DETR/models/transformer_decoder.py

Line 256 in df4e567

q_pos_scale = reference_boxes[:, :, 2:].reshape(bs, num_queries, 1, 2).expand(-1, -1, self.nheads, -1) * 0.5

I look forward to your valuable reply，Thank you.

[ZhangGongjie]

reference_boxes[:, :, 2:] represents the width and height of the reference boxes. We wish to control the sampling space within the reference space, so we multiply it by 0.5 as the scale of spatial sampling.