def forward(self, x):
    source = x[:, 0:1, :, :]
    (x, attn_weights, features) = self.transformer(x)
    x = self.decoder(x, features)
    flow = self.reg_head(x)
    out = self.spatial_trans(source, flow)
    return (out, flow)
def forward(self, x):
    source = x[:, 0:1, :, :]
    (x, attn_weights, features) = self.transformer(x)
    x = self.decoder(x, features)
    flow = self.reg_head(x)
    out = self.spatial_trans(source, flow)
    return (out, flow)