Most image scaling software has a flaw that can impact the quality of the results in varying degrees. For further details, you should read this article.
To test if your software is suffering from this flaw, take this exploit image:
When you resize it to 50%, you will probably see this:
However, if your software is working correctly, you should see:
Up until today, Transloadit was suffering from the aforementioned flaw, but we have fixed it. If you want to take advantage of the new gamma correction, simply specify
correct_gamma: true in your image resize Assembly Step. Check the docs for more information.