The playback of media files discussed in this article requires the co-operation and resources of both the device and the Sailfish OS. Even if Sailfish OS supported certain media format, it might be that the device hardware does not support it, which would result in a failure to use that media file.
Not all media codecs are free but require licenses. This may prevent using them.
Multimedia formats compatible with Sailfish OS
This chis a list of codecs supported by Sailfish OS.
Audio and video formats currently supported by Sailfish (OS version 3.2.1) are listed in chapter Format support at the end of the web page https://sailfishos.org/wiki/Multimedia.
JPEG, PNG, GIF
Only the files that require these codecs will appear in Sailfish Media (audio) and in Gallery (video & photo) applications.
If your Sailfish OS device does not seem to be able to use your media files in an expected way, please check first in the manual of your device that your device is capable of handling the type of media file you have at hand.
The next thing to check is if the media database of Sailfish OS is somehow corrupted. Please read this help article.