title: upconvolution implementation: where do the implementation come and effect of upsampling
body: <p>People implement the upconvolution in different ways. Basically one is to do fractional strided convolution, and the other is first upsampling the image and then do convolution. I saw the first one in implemntation of <a href="https://github.com/shelhamer/fcn.berkeleyvision.org/blob/master/voc-fcn8s/net.py#L68" rel="nofollow noreferrer">FCN</a> and UNet, however I haven't seen the second one in any official implementation of published paper. Wonder if anyone can point to an example of using the second approach in official source code of publication? </p>
  
  <p>Also, in the second approach, the upsampling function can have different behavior (say bilinear, linear, etc.) but authors of paper usually just say "upconvolution/upsampling". How to determine which kind of upsampling to use (except for trying each one to see the final result)? Or, it does not really matter? (didn't find paper on this topic)</p>