DVSESSIONDESC Structure

Describes the desired or current session settings for the Microsoft?DirectPlay?Voice server. This structure is used by the voice session host to configure the session, and by the session host and clients to retrieve information about the current session.

Syntax

typedef struct {
    DWORD dwSize;
    DWORD dwFlags;
    DWORD dwSessionType;
    GUID guidCT;
    DWORD dwBufferQuality;
    DWORD dwBufferAggressiveness;
} DVSESSIONDESC, *LPDVSESSIONDESC, *PDVSESSIONDESC;

Members

dwSize

Must be set the to size of this structure, in bytes, before using this structure.

dwFlags

Combination of the following flags.

DVSESSION_NOHOSTMIGRATION

The voice host will not migrate regardless of the transport settings. If this flag is not specified, the voice host will migrate if the transport supports it.

DVSESSION_SERVERCONTROLTARGET

The clients are unable to control the target of their speech. Only the server player can control the target of their speech. If the server does not specify this flag, only the clients can control the target of their speech. This flag can be specified only in multicast and mixing sessions.

dwSessionType

The type of DirectPlay Voice session to run. The DVSESSIONTYPE_PEER flag is not available in client/server sessions; all other flags are valid for all session types. This member can be one of the following values.

DVSESSIONTYPE_PEER

Voice messages will be sent directly between players.

DVSESSIONTYPE_MIXING

Voice session will use a mixing server. In this mode of operation, all voice messages are sent to the server, which mixes them and then forwards a single, premixed stream to each client. This reduces the bandwidth and CPU usage on clients significantly at the cost of increased bandwidth and CPU usage on the server.

DVSESSIONTYPE_FOWARDING

Voice messages will be routed through the session host. This will save bandwidth on the clients at the expense of bandwidth usage on the server. This option is only useful if the session host has a high-speed connection.

guidCT

GUID specifying the compression type of the session. To select the default compression codec, set this member to DPVCTGUID_DEFAULT.

dwBufferQuality

The buffer quality setting. This member is unused for all session types except mixing sessions. For all sessions except mixing sessions, set this member to DVBUFFERQUALITY_DEFAULT.

Allowable values are between DVBUFFERQUALITY_MIN and DVBUFFERQUALITY_MAX. Additionally, this member can be set to the following value.

DVBUFFERQUALITY_DEFAULT

Specifying this value tells DirectPlay Voice to use the system default for this value, which is adjustable through a registry entry that can also be set through Sounds and Multimedia in Control Panel.

dwBufferAggressiveness

Buffer aggressiveness setting. This member is unused for all session types except mixing sessions. For all sessions except mixing sessions, set this member to DVBUFFERAGGRESSIVENESS_DEFAULT.

Allowable values are between DVBUFFERAGGRESSIVENESS _MIN and DVBUFFERAGGRESSIVENESS _MAX. Additionally, this member can be set to the following value.

DVBUFFERAGGRESSIVENESS_DEFAULT

Specifying this value tells DirectPlay Voice to use the system default for this value, which is adjustable through a registry entry that can also be set through Control Panel.

Remarks

The dwFlags, dwSessionType, and guidCT members can only be set when the host starts the voice session. The host can change the buffer settings at any time.

Structure Information

Header	dvoice8.h
Minimum operating systems	Windows 98