Texas Instruments DM365, User Manual

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Simple Two-pass Encoding Sample Usage
E-4
9) Once the metadata is consumed and encoding is completed at high
resolution encoder, set the value of
metaDataGenerateConsume
flag
for low-resolution encoder instance to 1.
E.1 Example Usage:
In order to provide flexibility to generate/consume
metaData
information an
extended dynamic parameter
metaDataGenerateConsume
is provided.
Initially, it can take only three values: 0 (no
metaData
generated or
consumed), 1 (Generate
metaData
) and 2 (Consume
metaData
). In case of
low resolution encoder, we will set
metaDataGenerateConsume
to 1 and in
case of high resolution encoder
metaDataGenerateConsume
is set to 2.
Example settings for low resolution encoder
In this case, the application requests for buffers which are used to pass frame
level information from low resolution encoder to the high resolution encoder.
Set meetaDataGenerateConsume = 1
// generate metadata in low resolution encoder.
Output Buffer requirement by low resolution encoder
Structure Name Buffer Size
FrameInfo_Interface sizeof(FrameInfo_Interface);
MBInfo (uiSize >> 4) * 4;
MBRowInfo uiExtHeight * 4;
Where
uiSize
is the maximum number of pixels in a frame and
uiExtHeight
is the height of the frame in pixels.
Addresses of these buffers are passed to the codec where variables of the
structures (See Section 4.6) are updated if
metaDataGenerateConsume
is
set to 1. Once the encoding is completed, set the value of
metaDataGenerateConsume
flag for low-resolution instance to 3.
In current implementation,
MBinfo
and
MBRowinfo
structures are not
populated, hence no buffers are requested.
E.1.1 Example settings for high resolution encoder
In this case, the application copies the metadata information from the buffers
of low-resolution encoder to the buffers of high-resolution encoder. The high
resolution encoder makes use of frame level information as and when it is
required.
At application:
**********************************************************
If(metaDataGenerateConsume of low resolution is 3)
{
If(metaDataGenerateConsume of high resolution is 2)