Crossbar Thing 2.PNG
Has two drop down menus [Input] and [Output]
Its (not) Intuitive but these represent the [two-sides] of a box, In-side and Out-side
On those sides each has "pins" assigned Numbers
(for example )
Input (side)
0: Video Composite In
1: Video SVideo In
Output (side)
0: Video Decoder Out
========================
Input (side)
2: Audio Line In
Output (side)
1: Audio Decoder Out
You work [backwards] from the Output side selecting the Output pin of the Crossbar to "pick" the Input pin you want assigned to that Output pin.
So to select the Input pin to "map" to the Video Decoder Out - "first" select the Output pin [0: Video Decoder Out]
then the only choices you have in the drop down selector box on the "right" Input side will be related to "Video"
make the choice and click [Apply]
So to select the Input pin to "map" to the Audio Decoder Out - "first" select the Output pin [1: Audio Decoder Out]
then the only choices you have in the drop down selector box on the "right" Input side will be related to "Audio"
make the choice and click [Apply]
(In theory) you could have multiple possible Audio Input "sources"
(In theory) they could be
1: Tuner
2: Audio Line In
3: Mic In
ect... it all depends upon the device driver for the device and what it detects is offering a signal, devices that don't exist won't offer a source and would not enumerate a pin Number.. for various reasons.. it may not have a Tuner in this model, but the same hardware and device driver may work with a different combination that does have other sources
Just think of that [Tab] dialog box and two menu "sides" as a weird wacko proxy for the two sides of a [BOX] and those drop down selectors as "switches" for mapping or connecting sources to sinks.. of Inputs to Outputs
Its the Output that decides what shows up in the Input choices
And this "might help"
Notice that on each side of the [BOX] each possible pin set starts counting from [0], that is each side has a [0] choice, that's because all of the pins on the same side of the box are part of a "set" of Inputs, or "set" of Outputs.. they may be different signal types.. but they are on the same side of that imaginary [BOX]
It won't let you map a possible video source to an audio output
[Notice too] that you can change the "Default" [Related Pin:] by first selecting the Output pin for Video and then picking its Input pin. The Related Pin will always be "2: Audio Line In" but after you press [Apply] it will be "stuck" to that video input.. if you then select the Output pin for Audio, the Related Pin: will be whatever you confirmed with the last Apply for video.
(In theory) with multiple Audio Input sources, like a Tuner or Mic input.. you could do the reverse and "glue" a Video pin with a specific Audio input and press [Apply].. but for this device you cannot.. its a degenerate case that doesn't show off the robustness of this fictional "Crossbar" way of connecting things
Its a lot more intuitive when you see it in GraphEdit.. but works if all you have is this simplified "control sheet".
I think a checkbox matrix would be easier.. but someone thought drop down menus were neater and less cluttered.
also.. [Related Pin:] has nothing to do with [Link Related Streams] .. Pins and Streams are different things
the [Link Related Streams] checkbox is an "optional" control on this boilerplate design, it may do nothing at all.. its like many controls on property pages for the device driver, proc-amp and so forth.. it has to appear there.. and the device driver can "grey" it out if it "wants too".. but the lazy way is simply not design any code to change it one way or another.. if it does nothing checking or unchecking it will do nothing.. quite often it does nothing in many drivers/filters
the "telling thing" is when you check the box and the [Apply] button does not light up as a clickable button.. basically nothing happened thats important to the driver/filter as far as its concerned "no difference" has been made
its real purpose I believe was when this property page was servicing DV video and the user could select different audio tracks in the same video stream.. but thats an archaic bit of trivia these days.. a relic from the past
this familiar design is still called up when designing a device driver, but only some of the controls actually do anything.. actually for this page.. most of the controls do something
