Texas Instruments DM365, Руководство пользователя

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Introduction
1-4
from which the
process()
call is made can be used by the application in
parallel with the encode or the decode operation. To enable this, the
framework provides flexibility to the application to pend the encoder task
when the frame level computation is happening on coprocessor.
Apart from defining standardized APIs for multimedia codecs, XDM also
standardizes the generic parameters that the client application must pass
to these APIs. The client application can define additional implementation
specific parameters using extended data structures.
The following figure depicts the XDM interface to the client application.
As depicted in the figure, XDM is an extension to XDAIS and forms an
interface between the client application and the codec component. XDM
insulates the client application from component-level changes. Since TI’s
multimedia algorithms are XDM compliant, it provides you with the flexibility
to use any TI algorithm without changing the client application code. For
example, if you have developed a client application using an XDM-
compliant MPEG4 video decoder, then you can easily replace MPEG4 with
another XDM-compliant video decoder, say H.263, with minimal changes
to the client application.
For more details, see eXpressDSP Digital Media (XDM) Standard API
Reference (literature number SPRUEC8).
1.2.3 Framework Component
As discussed earlier, Framework Component acts like a middle layer
between the codec and OS and also serves as a resource manager. The
following block diagram shows the FC components and their interfacing
structure.
XDAIS Interface (IALG)
TI’s Codec Algorithms
XDM Interface
Client Application