How do I change MAME's recording files

[StarmanElite]

So mame has the ability to record in original pixel size which is handy for sprite ripping, but it saves the recordings as .mng files   (which are annoying to convert to gif). So my Question is how do i make it so Mame saves the recordings as .gif instead of .mng . Please respond soon, thank you for your time -StarmanElite