Texas Instruments DM6467, Руководство пользователя

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Introduction
1-3
(for example audio, video, image, and speech). The XDM standard defines
the following two APIs:
‰
control()
‰
process()
The
control()
API provides a standard way to control an algorithm
instance and receive status information from the algorithm in real-time. The
control()
API replaces the
algControl()
API defined as part of the
IALG interface. The
process()
API does the basic processing
(encode/decode) of data.
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).
Client Application
XDAIS Interface (IALG)
TI’s Codec Algorithms
XDM Interface
1.2 Overview of H.264 1080p@30 Baseline Profile Encoder
H.264 is the latest video compression standard from the ITU-T Video
Coding Experts Group and the ISO/IEC Moving Picture Experts Group.
H.264 provides greater compression ratios at a very low bit-rate. The new
advancements and greater compression ratios at a very low bit-rate has
made devices ranging from mobile and consumer electronics to set-top
boxes and digital terrestrial broadcasting to use the H.264 standard.