MPEG_STREAM_BUFFER Structure

The MPEG_STREAM_BUFFER structure defines a buffer that receives MPEG-2 data.

Syntax

typedef struct {
  HRESULT hr;
  DWORD dwDataBufferSize;
  DWORD dwSizeOfDataRead;
  BYTE *pDataBuffer;
} MPEG_STREAM_BUFFER, 
 *PMPEG_STREAM_BUFFER;

Members

• hr
  Specifies a status code. Use this value to check the status of the read request.

• dwDataBufferSize
  Specifies the size of the buffer, in bytes.

• dwSizeOfDataRead
  Specifies the amount of valid data in the buffer, in bytes

• pDataBuffer
  Pointer to a buffer that holds the MPEG-2 data.

Remarks

This structure is used with the IMpeg2Stream::SupplyDataBuffer method to get raw MPEG-2 data.

For PSI tables and sections, set pDataBuffer to point to a SECTION structure. If you also create an MPEG_PACKET_LIST structure to hold a list of buffers, you can pass that list to the ISectionList::InitializeWithRawSections method.

The following code shows how to initialize an MPEG_STREAM_BUFFER structure so that it points to a SECTION structure contained in an MPEG_PACKET_LIST section list:

// Allocate two buffers for section data.
const int cBufferSize = 4096;
BYTE pBuffer1[cBufferSize];
BYTE pBuffer2[cBufferSize];

// Create a packet list to hold both buffers.
MPEG_RQST_PACKET RqstPacket[2];
MPEG_PACKET_LIST Packets;

RqstPacket[0].dwLength = cBufferSize;
RqstPacket[0].pSection = (SECTION*)pBuffer1;
RqstPacket[1].dwLength = cBufferSize;
RqstPacket[1].pSection = (SECTION*)pBuffer2;

Packets.wPacketCount = 2;
Packets.PacketList[0] = &RqstPacket[0];
Packets.PacketList[1] = &RqstPacket[1];

// Set the stream buffer structure to point to the first packet in the list.
MPEG_STREAM_BUFFER StreamBuffer;
ZeroMemory(&StreamBuffer, sizeof(MPEG_STREAM_BUFFER));
StreamBuffer.dwDataBufferSize = Packets.PacketList[0]->dwLength;
StreamBuffer.pDataBuffer = (BYTE*) Packets.PacketList[0]->pSection;

Requirements

See Also

BDA Structures

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Build date: 12/4/2008