許多CNN網路都有Fusion layer作為融合層，比如：

參考：https://arxiv.org/pdf/1712.03400.pdf

相關程式碼：（https://github.com/baldassarreFe/deep-koalarization/blob/master/src/koalarization/fusion_layer.py）

class FusionLayer(Layer):
    def call(self, inputs, mask=None):
        imgs, embs = inputs
        reshaped_shape = imgs.shape[:3].concatenate(embs.shape[1])
        embs 
 
= K.repeat(embs, imgs.shape[1] * imgs.shape[2])
        embs = K.reshape(embs, reshaped_shape)
        return K.concatenate([imgs, embs], axis=3)

當我實際去做的時候，K.reshape 報錯：ValueError: Tried to convert 'shape' to a tensor and failed. Error: Cannot convert a partially known TensorShape to a Tensor

 reshaped_shape = enco_loco.shape[:3].concatenate(enco_glob.shape[1])
    fuse 
 
= K.repeat(enco_glob, enco_loco.shape[1]*enco_loco.shape[2])
    fuse = K.reshape(fuse, (reshaped_shape))
    fuse = K.concatenate([enco_loco, fuse], axis=3)

相關資訊：

enco_loco:(None, 16, 16, 512)
enco_glob:(None, 512)
reshaped_shape:(None, 16, 16, 512)
enco_glob.shape:(None, 512)
fuse.shape:(None, 256, 512)

最後想把fuse從(None, 256, 512) 變成(None, 16, 16, 512) 就出現上述錯誤。

解決方法：

fuse = K.reshape(fuse, (-1, reshaped_shape[1], reshaped_shape[2], reshaped_shape[3]))

參考：https://github.com/matterport/Mask_RCNN/issues/1070