IWMProfile3::GetExpectedPacketCount method (wmsdkidl.h)
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The GetExpectedPacketCount method calculates the expected packet count for the specified duration. The packet count returned is only an estimate, and it is based upon the settings of the profile at the time this call is made.
Syntax
HRESULT GetExpectedPacketCount(
[in] QWORD msDuration,
[out] QWORD *pcPackets
);
Parameters
[in] msDuration
Specifies the duration in milliseconds.
[out] pcPackets
Pointer to receive the count of packets expected for msDuration milliseconds.
Return value
The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.
| Return code | Description |
|---|---|
|
The method succeeded. |
|
pcPackets is NULL. |
|
One of the internal objects required by the method could not be initialized. |
|
The profile in the profile object is not compatible with this method. |
Remarks
Problems will arise if the value passed in msDuration is not a positive number of milliseconds. The method will return S_OK as normal, but the packet count returned will not be correct.
It is impossible for this method to give exact counts, because there is no way to account for interleaved data in an encoded file. The packet count returned is most accurate for files with one audio stream. The more complicated the profile, the less accurate the packet count will be.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only],Windows Media Format 9 Series SDK, or later versions of the SDK |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | wmsdkidl.h (include Wmsdk.h) |
| Library | Wmvcore.lib; WMStubDRM.lib (if you use DRM) |