DVB abstractions: filters and feeds

[Marc Gonzalez]

Hello,

I'm having a hard time understanding two abstractions in the DVB framework,
namely filters and feeds (P.S. I now see there are dvb_demux_filter's and
dmxdev_filter's, so it's really 3 abstractions that I'm not grasping.)

Specifically,

struct dvb_demux {
	...
	int filternum;
	int feednum;
	struct dvb_demux_filter *filter;
	struct dvb_demux_feed *feed;

and

struct dmxdev {
	...
	struct dmxdev_filter *filter;
	int filternum;


Also, I'm not sure about the relationship between dvb_demux and dmxdev.
Should they have the same filternum for a given adapter instance?

Basically, could someone shed a bit of light on these topics?


https://linuxtv.org/downloads/v4l-dvb-apis-new/kapi/dtv-demux.html?highlight=dmxdev#c.dmxdev
struct dmxdev : "Describes a digital TV demux device." /me puzzled

https://linuxtv.org/downloads/v4l-dvb-apis-new/kapi/dtv-demux.html?highlight=dvb_demux#c.dvb_demux
struct dvb_demux : "represents a digital TV demux"


Regards.