Matrox M264, Инструкция по установке и эксплуатации

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Chapter 6, Using the Matrox M264 Hardware Codecs
Decompression operation
The following steps explain how to control the Matrox M264 hardware decoder using
the
IMvDecoderVideo
interface.
1
Instantiate the Matrox M264 decoder codec GUID,
CLSID_MvM264Decoder
,
using the
CreateCodecEx()
method of the
IMvFlexEngine
interface.
For more information on the
IMvFlexEngine
interface, see “Overview of the
Flex Engine” in the Matrox DSX.sdk User Guide or “Obtaining a Flex Engine for
processing buffers using the card configuration interface” in the Matrox DSX
Topology API User Guide.
2
Allocate a pool of Flex user buffers that will be used for the compressed data.
For information on allocating buffers, see “Audio/video surface allocation and
management” in the
Matrox DSX.sdk User Guide or “Using buffers to update a
card node” in the Matrox DSX Topology API User Guide .
3
Allocate a pool of uncompressed Flex host buffers (YUV 4:2:2 8-bit,
YUV 4:2:2 10-bit, or v210 4:2:2 10-bit) that will receive the uncompressed
images.
4 Call
IMvDecoderVideo::Open()
to open a stream for decoding and pass a
pointer to the
SMvM264DecompressionOptions
structure.
5
The user application must implement the completion observer interface using
IMvCompletionObserver::NotifyCompletion()
and set a notification
callback by calling
IMvDecoderVideo::SetOption()
with the
keMvCodecOptionFlushObserver_pI
parameter.
¦ Note
The notification will be called once the codec is finished decoding all the
data and after
IMvDecoderVideo::Flush()
is called. The user application calls
IMvDecoderVideo::Flush()
when it is finished passing all the compressed data
to the codec.
6
The user application must implement the error notification callback interface
using
IMvErrorNotificationCallback::Notify()
and set an asynchronous
error notification callback by calling
IMvDecoderVideo::SetOption()
with
the
keMvCodecOptionAsynchErrorCallback_pI
parameter.
¦ Note
This allows the user application to handle decoder errors.