E. Dual-direction short connection fusion module

HRFormer applies transformer blocks to enlarge receptive field of fused feature Frs, and uses exchange units to absorb the merits of multi-scales features. The process is described as:

HRFormer使用TRM块来扩大融合特征Frs的感受野，并使用交换单元来吸收多尺度特征的优点。该过程描述如下：
After HRFormer, output features F o = {fio }4i=1 achieve information exchange and optimization in both global and local scopes.
在HRFormer之后，输出特征Fo 在全局和局部范围内实现信息交换和优化。
f1rs f2rs f3rs f4rs ->HRFormer-> f1o f2o f3o f4o

Next, aggregating information from output features fio(i = 1, · · · , 4) of HRFormer is an essential operation for dense pre- d