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About IMFRateSupport::IsRateSupported. RRS feed

  • Question

  • <<Question1.>>
     About third parameter receives value.
     It differ from SDK help description.  why?
    ※SDK use version 8.0.50727.42 RTM

    [detail]
     Basicplayback sample is customized to support RateControl.
      Below is testcode.

     float rateRequested = 5.0;
     float actualRate = 0;
     hr = pRateSupport->IsRateSupported(
         FALSE,
         rateRequested,
         &actualRate );

      The third parameter is expected "2.0" but returned "5.0".

    <<Question2.>>
      About the third parameter of IsRateSupported decsribed in the SDK Documentation.

      The type is described [in].
      But according to the explanation of "the parameter receives...", it seems [out].
      Whitch is right, [in] or [out]?

    Thursday, December 21, 2006 5:10 AM

Answers

  • From the SDK docs:

    If the object does not support the playback rate given in flRate, this parameter receives the closest supported playback rate. If the method returns S_OK, this parameter receives the value given in flRate.

    You didn't indicate the return value in your post, but if actualRate receives 5.0, it means the playback rate you requested is in fact supported.

    Regarding [in] or [out], I don't have the header file in front of me, but what you wrote sounds correct, it should be an [out] parameter. I'll follow up on that. (Possibly it's just an error in the documentation.)

    ----------------------------------------------------------------------------
    Mike Wasson, SDK Documentation
    This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

    (c) 2006 Microsoft Corporation. All rights reserved.

    Thursday, December 21, 2006 11:50 PM

All replies

  • Perhaps the graph you are using only supports a max of 2.0.
    Thursday, December 21, 2006 9:46 AM
  • From the SDK docs:

    If the object does not support the playback rate given in flRate, this parameter receives the closest supported playback rate. If the method returns S_OK, this parameter receives the value given in flRate.

    You didn't indicate the return value in your post, but if actualRate receives 5.0, it means the playback rate you requested is in fact supported.

    Regarding [in] or [out], I don't have the header file in front of me, but what you wrote sounds correct, it should be an [out] parameter. I'll follow up on that. (Possibly it's just an error in the documentation.)

    ----------------------------------------------------------------------------
    Mike Wasson, SDK Documentation
    This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

    (c) 2006 Microsoft Corporation. All rights reserved.

    Thursday, December 21, 2006 11:50 PM