Improve the way PNGs are converted to JPG

[craigymunro]

If you have a PNG with transparencies and then run it through a JPG conversion the image often contains graphical glitches. Here's an example:

Original:
https://images.eurogamer.net/2014/gamersedition/papers-please/poster.png

Corrupted:
https://images.eurogamer.net/2014/gamersedition/papers-please/poster.png/EG11/format/jpg

Is there anything we can do to improve the way it's flattened? Maybe always matte it to a white background?

[craigymunro]

Here is another example.

Original:
https://images.eurogamer.net/2014/craig/XboxOne_Controller_620.png

Corrupted:
https://images.eurogamer.net/2014/craig/XboxOne_Controller_620.png/EG11/format/jpg