Some years ago I played around with Gstreamer quite a lot. Gstreamer is an open source multimedia framework which allows you to deal with video and audio sources of any kind and play, convert or mux them to your needs.
The nice thing with Gstreamer is the fact, that it is very powerful on the one hand, but very good to test and play around
with on the other hand. For example it provides tools to run and inspect the various filters, sources
and converters easily. Also it has bindings to e.g. Python, so you can use them in a native way, without the
need to run shell commands from within your script.
Yesterday I found, that Gstreamer also has
siddec decoder, which allows you to deal with SID files. So this blog
post is about playing retro C64 SID files with Gstreamer.