I have been using DirectFB for some time now and have always had an issue
with Outputs and Encoders.

Encoders have the ability to set TVStandards and Output Signals.
Outputs have the ability to set OutputSignals and Connectors.
This implies I think (Please correct if worng a model like this)

---------------------------------------
|                                    |
|  Outputs         |--------------   -----> Physical Output (ie SCART etc)
|                      | Encoders|
---------------------------------------


This (if correct) probably matches how people consider a PC GFX card

However in the embedded world the model is more like this

---------------------------                                      
------------------                             
|                         |                                      |              
 
|
|    Output           |  ---> A Fixed SIGNAL -->   |  Encoder   | ->
Physical Output
|-------------------------|                                     
-------------------

This is because an Encoder in our case can be mapped directly to a VideoDenc
which is capable of controlling the type of output signal RGB etc and the
connector to which it goes.

The next problem is that one output may have 2 encoders.  One that is
capable of outputting HDMI (ie the encoder is a HDMI encoder) and another
that outputs RGB ->SCART.
This is very difficult if the output is under the control of connectors.

To solve this problem I have a proposal which is to extend Encoders to have
the Output Connectors ENUM and move the recently added SlowBlanking ENUM
into Encoders as well.
I would also add an output signal of DSOS_DIGITAL.

This suggestion should be backwards compatible with the Current DFB apps.  

But it would allow me to indicate the capabilites of my Output to not have
connectors or selectable connectors and only supports the output of a
digital signal.

I could then have an encoder that supports changing output signal, output
connector and any slow blanking that is valid.

This would allow me to have 2 encoders for a single output and configure
them independently. Both could recieve a Digital signal and encode them, one
to say RGB and output to scart the other could encode to Component YPrPb
signal.

Is my understanding of Encoders and Outputs correct?
Do people think my proposal is a fair one.  I am working on it now.  Would
people support the addition of these enums to Encoder API.

Cheers
Dan




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