Issue title: Question on wrong results
 Issue body: Hello, zjuela.

First of all I really appreciate your source code.
Now I'm running this code on my computer (window10 64bit) by just modifying some parameters which should be changed in order to operate on the latest library version. 
However, there is a problem as shown in the attached image.
This image is a 2x scaled image as an output of the code. 
I couldn't find the reason why the image has wrong result data. 
Did you experienced this problem before? or Do you have any idea to solve this problem? 

![test_out](https://user-images.githubusercontent.com/48550067/54345255-0aaa3680-4686-11e9-98fb-1539cafd180a.png)

 Comments: 
 Comment 0: Hello, zjuela.

I finally found that this problem can be resolved by using older version of included libraries. 
I could not know which libraries are the reason of the problem, but maybe one or more of tensorlayer, scipy, scikit-image, and easydict are doubted. 
It'd be better to upgrade your code by using the latest libraries. 
Anyway, your code was very helpful to me. Thank you. 
 Comment 1: @yjyoon7  Thanks for reporting this. The results look like image format problem. So I would recommend checking the image format when saving and displaying the figure.

{'source': 'GithubIssues', 'repo_name_with_owner': 'zjuela/LapSRN-tensorflow', 'issue_id': 420912666, 'repo_stars': 115.0}