Class TAvcHrdParams

class TAvcHrdParams;

Description

TAvcHrdParams specifies a set of AVC-specific HRD parameters. All pointers included in the objects have the same lifetime as the objects themselves, and the memory is allocated and deallocated by the same instance that creates and owns the object.

Members

Defined in TAvcHrdParams:
TCpbParams, iDpbSize, iLowDelayHrd, iNalCpbCount, iNalCpbParams, iVclCpbCount, iVclCpbParams

class TCpbParams;

Description

Members

Defined in TAvcHrdParams::TCpbParams:
iBitrate, iCbr, iCpbSize, iInitialCpbRemovalDelay, iInitialCpbRemovalDelayOffset

Member data

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iInitialCpbRemovalDelay

TUint iInitialCpbRemovalDelay;

Description

Specifies the delay for a CPB between the time of arrival in the CPB of the first bit of the coded data associated with the access unit associated with the buffering period SEI message and the time of removal from the CPB of the coded data associated with the same access unit, for the first buffering period after HRD initialisation. It is in units of a 90 kHz clock. The value is equal to the corresponding initinal_cpb_removal_delay of the NAL HRD parameters if the current parameter is for the NAL HRD or of the VCL HRD parameters if the current parameter is for the VCL HRD.

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iInitialCpbRemovalDelayOffset

TUint iInitialCpbRemovalDelayOffset;

Description

This parameter is used for a CPB in combination with the cpb_removal_delay to specify the initial delivery time of coded access units to the CPB. It is in units of a 90 kHz clock. The value is equal to the corresponding initinal_cpb_removal_delay_offset of the NAL HRD parameters if the current parameter is for the NAL HRD or of the VCL HRD parameters if the current parameter is for the VCL HRD.

Note: Over the entire coded video sequence, the sum of iInitialCpbRemovalDelay and the corresponding iInitialCpbRemovalDelayOffset shall be constant for either the NAL HRD parameters or the VCL HRD parameters.

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iCbr

TBool iCbr;

Description

Equal to EFalse specifies that to decode this bitstream by the HRD using the CPB specification, the hypothetical stream scheduler (HSS) operates in an intermittent bit rate mode. Equal to 1 specifies that the HSS operates in a constant bit rate (CBR) mode.

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iBitrate

TUint iBitrate;

Description

Specifies the maximum input bit rate, in bits per second, of a CPB. The value is equal to Bitrate as specified in subclause E.2.2 of the AVC specification.

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iCpbSize

TUint iCpbSize;

Description

Specifies the size, in bytes, of a CPB. The value is equal to CpbSize/8, where CpbSize is as specified in subclause E.2.2 of the AVC specification.

TUint iDpbSize;

Description

Specifies the required size of the decoded picture buffer (DPB) in unit of bytes. The value is equal to max_dec_frame_buffering* PicWidthInSamplesL*FrameHeightInMbs*2, where PicWidthInSamplesL and FrameHeightInMbs are specified in subclause 7.4.2.1 of the AVC specification amd the syntax element max_dec_frame_buffering as specified in subclause E.2.1 of the AVC specification.

TBool iLowDelayHrd;

Description

Specifies the HRD operational mode as specified in Annex C of the AVC specification. The value of LowDelayHrd is equal to ETrue if the syntax element low_delay_hrd_flag is equal to 1, and EFalse otherwise. This parameter is valid only if at least one of iNalCpbCount and iVclCpbCount is larger than 0.

TUint iNalCpbCount;

Description

Specifies the number of alternative coded picture buffer (CPB) specifications for NAL HRD parameters in the bitstream. The value of iNalCpbCount is equal to cpb_cnt_minus1 + 1 in the NAL HRD parameters, if present. iNalCpbCount equal to 0 means that NAL HRD parameters are not present.

TCpbParams * iNalCpbParams;

Description

Valid only if iNalCpbCount is larger than zero. iNalCpbParams is a pointer to an object of TCpbParams, which contains the parameters of an alternative CPB.

TUint iVclCpbCount;

Description

Specifies the number of alternative coded picture buffer (CPB) specifications for VCL HRD parameters in the bitstream. The value of iVclCpbCount is equal to cpb_cnt_minus1 + 1 in the VCL HRD parameters, if present. iVclCpbCount equal to 0 means that VCL HRD parameters are not present.

TCpbParams * iVclCpbParams;

Description

Valid only if iVclCpbCount is larger than zero. iVclCpbParams is a pointer to an object of TCpbParams, which contains the parameters of an alternative CPB.