Table Of Contents:
Introduction
The current CELF AVG 1.0 spec specifies DirectFB for graphics, and UHAPI is proposed as part of the CELF AVG 2.0 specification for controlling the Audio and Video. This section specifies how DirectFB and UHAPI can go together in the CELF AVG spec.
Rationale
The main focus of DirectFB is Graphics, and the main focus of UHAPI is Audio and Video control. Both use very similar interface technology (Vtable based interfaces, and explicit functional interfaces (not ioctrl based).
The abstraction level of DirectFB and UHAPI is also very similar. Both provide primitive interfaces to abstract the acceleration HW (different HW platforms), and focus on providing the middleware with a cross platform control interface.
Both DirectFB and UHAPI provide mechanism to compose different layers (video and gfx) into one output (e.g. by means of blending). This is exactly the area where DirectFB and UHAPI meets.
For the CELF AVG spec 2.0 it is important to describe exactly the relation between DirectFB and UHAPI to come to a clear specification.
Note that DirectFB is both an interface specification and an implementation. In this context we are only referring to the interface specification.
Specifications
The UHAPI Video Mixer specification (uhIVmix.pdf)
How can DirectFB and UHAPI go together?
This presentation shows how DirectFB and UHAPI go together (13/14th June, Yokohama, Japan) DirectFB_UHAPI.pdf
This diagram roughly shows how UHAPI and DirectFB can go together
[Explain the relation]
[Add link to XLS sheet with details on how DirectFB and UHAPI can go together]
[Add list of core elements of DirectFB?]
[Add list of core interfaces that should exist in the "CELF Profile"?]
[Add list of interfaces considered "not part of the CELF Profile"?]
Future Work
[Work out in more detail and readable format the overview of the UHAPI / DirectFB relation on a function level (complete preliminary sheet.]