Feature Map Shape Problem

[ZeningLin]

According to Figure 2 in the paper, the author did not apply downsampling in the first a block, but I found that in chargrid2d/model.py downsampling was applied in self.block1, thus dividing the height/width of all feature maps by factor 2. I guess that this adaption may help with the shape mismatch problem in the subsequent lateral connection step, as the descriptions of this part in the paper is ambiguous. Do you have any idea on concatenating two feature maps in different shapes if I did not apply downsampling at the beginning?