Matrox M264, Инструкция по установке и эксплуатации

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About the Matrox M264 hardware decoder
7
Allocate a sufficient amount of memory to hold the compressed data, and then
call
IMvSurface::AssignUserBufferReference()
to assign the memory to
the user buffer surfaces created in step 2 . Use a surface description that matches
the decoder input resolution and the
keMvSurfaceFormatAVC
parameter as the
surface format.
Remarks
$
If the size of each compressed frame is known, the user buffer surface can
reference that size.
$
If the bit rate is not known, allocating 512 KB is sufficient.
$
If the bit rate is known, it can be used to estimate the average size of one frame
of compressed data.
8 Set up the
IMvAVContent
interface of these compressed buffers with correct
read and write counts. Once the write operation is finished, call
IMvAVContent::SignalWriteCompletion()
to signal that the surface is
ready to be used by the decoder.
For information on working with buffers, see “Synchronizing surface operations”
in the
Matrox DSX.sdk User Guide or “Working with buffers” in the Matrox DSX
Topology API User Guide .
9 Call
IMvDecoderVideo::PutCompressedSurface()
for each prepared user
buffer in the order that they were read.
10
Set up the
IMvAVContent
interface for the buffers created in step 3 and call
IMvDecoderVideo::GetUncompressedVideoAndVANCSurface()
with
these buffers.
Remarks
$
Because VANC surfaces are not supported yet, set VANC surfaces to
NULL
.
$
IMvDecoderVideo::GetUncompressedVideoAndVANCSurface()
can
be called until all the buffers from the pool are sent to the decoder and as
buffers are returned to the pool.
$
To ensure that the decoder is not slowed down because it does not have buffers
at the input or output, call
IMvDecoderVideo::
PutCompressedSurface()
and
IMvDecoderVideo::
GetUncompressedVideoAndVANCSurface()
with as many buffers
available from the pool.
11 Continue the
IMvDecoderVideo::PutCompressedSurface()
and
IMvDecoderVideo::GetUncompressedVideoAndVANCSurface()
loop
until all compressed data has been sent to the decoder.