GStreamer contains a bunch of conversion plugins that most
applications will find useful. Specifically, those are videoscalers
(videoscale), colorspace convertors (ffmpegcolorspace), audio format
convertors and channel resamplers (audioconvert) and audio samplerate
convertors (audioresample). Those convertors don't do anything when not
required, they will act in passthrough mode. They will activate when
the hardware doesn't support a specific request, though. All
applications are recommended to use those elements.