Advancing images doesn't follow numerical ordering

[EpicEric]

For the following directory structure:

IMG1.png
IMG2.png
IMG3.png
...
IMG10.png
IMG11.png
IMG12.png
...
IMG20.png
...
IMG100.png
IMG101.png

Instead of following the natural sorting above (which takes numbers into account, like most file managers do), the files are navigated in naive alphabetical order:

IMG1.png -> IMG10.png -> IMG100.png -> IMG101.png -> IMG11.png -> IMG12.png -> ... -> IMG2.png -> IMG20.png -> ... -> IMG3.png -> ...