Texas Instruments DM365, User Manual

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API Reference
4-41
Multiple slices based on number of MBs per slice and number of
rows per slice.
‰ Platinum mode Mode(
encQuality
= 2): Multiple slices based
on number of rows per slice.
4.2.2.2 IH264VENC_DynamicParams
║
Description
This structure defines the run-time parameters and any other
implementation specific parameters for a H.264 Encoder instance object.
The run-time parameters are defined in the XDM data structure,
IVIDENC1_DynamicParams
.
║
Fields
Field Data type Input/
Output Description
videncDynamicPara
ms IVIDENC1_Dy
namicParams
Input See
IVIDENC1_DynamicParams
data structure
for details.
The size parameter of
DynamicParams
is set to
size of
IVIDENC1_DynamicParams
structure by
default while using extended parameters.
intraFrameQP XDAS_Int32 Input Quantization Parameter (QP) of I-frames in fixed QP
mode. Valid value is 0 to 51. It is useful only when:
‰
rateControlPreset of
IVIDENC1_Params
is equal to
IVIDEO_NONE .
‰
RcAlgo
= 2 (Fixed QP)
‰
targetBitRate
= 0
Default value = 28
interPFrameQP XDAS_Int32
Input Quantization Parameter (QP) of P-frames in fixed
QP mode. Valid value is 0 to 51. It is useful only
when:
‰
rateControlPreset of
IVIDENC1_Params
is equal to
IVIDEO_NONE .
‰
RcAlgo
= 2 (Fixed QP)
‰
targetBitRate = 0
Default value = 28
initQ XDAS_Int32 Input Initial Quantization (QP) for the first frame. Valid
values include -1 and any value between 0 to 51.
The parameter is applicable only when rate-control
is enabled. Should be set based on the target bit-
rate.
Default value = 28
Recommended value = -1. When -1 is used,
encoder calculates initial Qp based on bit rate, frame
rate and input resolution. This calculated Qp value is
used for first frame.