A selected input stream or the result of a filter.

Obtain a stream with an indexed helper such as FFix.video/3, a FFix.Filter function, or FFix.Graph.export/2. Pass it to another filter, an encoder, or an output. These functions manage the reference for you.

A stream retrieved from a graph retains the graph's other branches. See FFix.Graph for keeping them connected, and FFix.Selection for output queries that may match several tracks.