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AVCSTRM_FORMAT_INFO structure (avcstrm.h)

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The AVCSTRM_FORMAT_INFO structure is used to describe a data stream.

Syntax

typedef struct _AVCSTRM_FORMAT_INFO {
  ULONG          SizeOfThisBlock;
  AVCSTRM_FORMAT AVCStrmFormat;
  CIP_HDR1       cipHdr1;
  CIP_HDR2_SYT   cipHdr2;
  ULONG          SrcPacketsPerFrame;
  ULONG          FrameSize;
  ULONG          NumOfRcvBuffers;
  ULONG          NumOfXmtBuffers;
  DWORD          OptionFlags;
  ULONG          AvgTimePerFrame;
  ULONG          BlockPeriod;
  ULONG          Reserved[4];
} AVCSTRM_FORMAT_INFO, *PAVCSTRM_FORMAT_INFO;

Members

SizeOfThisBlock

Specifies the size of this data structure, in bytes.

AVCStrmFormat

Specifies one of the AV/C streaming subunit formats defined in AVCSTRM_FORMAT.

cipHdr1

Specifies the definition of the first quadlet of the two quadlet CIP header.

cipHdr2

Specifies the definition of the second quadlet of the two quadlet CIP header.

SrcPacketsPerFrame

Specifies the number of source packets to fill a data frame.

FrameSize

Specifies the data buffer size.

NumOfRcvBuffers

Specifies the number of receiving buffers.

NumOfXmtBuffers

Specifies the number of transmitting buffers.

OptionFlags

Specifies any option flags. Currently, only one flag is defined:

Flag Description
AVCSTRM_FORMAT_OPTION_STRIP_SPH Strip the SPH (source packet header) from the 192-byte data packet for MPEG2TS.

AvgTimePerFrame

Specifies the average time per frame in 100 nanosecond units.

BlockPeriod

Specifies the block period. This is used for transmit only. It is calculated from 1/ BlockPerSecond 1,000,000,000 picoseconds. For SDDV, it transmits one block per 1394 cycle. 1/(29.97 250) * 1,000,000,000,000 = 133,466,800 picoseconds.

Reserved[4]

Reserved. Do not use. Must be set to 0.

Requirements

Requirement Value
Header avcstrm.h (include Avcstrm.h)

See also

AVCSTRM_FORMAT

CIP_HDR1

CIP_HDR2_FDF

CIP_HDR2_MPEGTS

CIP_HDR2_SYT