Jeremy Noring
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 Posted:
Tue Sep 28, 2004 9:03 pm Post subject:
Questions concerning WMV and SetRate() |
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It's been a known issue that the SetRate command does not work with the WM
ASF Reader filter for some time now--see this post by Michael Blome (dated
June 26, 2003) for more information:
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=OmfsljDPDHA.3144%40tk2msftngp13.phx.gbl
I have a few questions that I was hoping someone from MSFT could help me
with--I know that I can't expect a reply from a MSFT employee, but I'm
hoping someone has done something to resolve this issue as it's well over a
year old now.
1. Has the issue with SetRate been resolved in the 9.5 release of the
WMFSDK? Does the IMediaSeeking::SetRate command work when using the
interface on the WM ASF Reader? I have had no luck personally, but perhaps
someone else has had success using this interface method?
2. Today I tried to use the IAMExtendedSeeking interface on the WM ASF
Reader to see if I would have any luck there, but encountered no positive
results. I use the following code:
IAMExtendedSeeking *pES = NULL;
double speed;
HRESULT hr = pWMASFReader_PB->QueryInterface( IID_IAMExtendedSeeking, ( void
** ) &pES );
hr = pES->get_PlaybackSpeed( &speed ); // return S_OK
long pexcapabilities;
hr = pES->get_ExSeekCapabilities( &pexcapabilities ); // returns 49 for
my file, indicating seek but no scan capabilities
speed *= 2;
hr = pES->put_PlaybackSpeed( speed ); // return error code (0x80070057)
E_INVALIDARG
Am I doing something incorrectly above? The above code returns E_INVALIDARG
for the call to put_PlaybackSpeed. However, when I open the exact same
video clip in the WMP10, I'm able to seek and fast-forward with no
difficulty. Why is this functionality not being made available to
developers as well? It's an enormous problem developing a comprehensive
media application with the WMV codecs when you can't do something so
inherently basic to video playback.
Pardon me and my high horse, but if Microsoft is really serious about WMV as
an entertainment platform, this is something that developers need to be able
to leverage in their applications.
3. Assuming neither of the above options are going to work for me, my
question becomes: what development options do I have? I believe the only
option appears to be writing a custom DirectShow source filter that
internally uses the WMF (and, most specifically, the
IWMReaderAdvanced3::StartAtPosition method to specify the playback rate).
Sure, this is possible, but it seems like a terrible waste when that
functionality is present in the WMP10. Do I really need to re-invent the
wheel here, or is there some option that's easier for developers?
You'll have to excuse my ranting, but I'd just like to see some resolution
and/or movement on this issue.
Thanks in advance,
jer
--
Where am I going?
And why am I in this handbasket?
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The March Hare [MVP]
Guest
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| Posted:
Wed Sep 29, 2004 7:37 pm Post subject:
Re: Questions concerning WMV and SetRate() |
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On Tue, 28 Sep 2004 11:03:37 -0600, Jeremy Noring wrote:
| Quote: | It's been a known issue that the SetRate command does not work with the WM
ASF Reader filter for some time now--see this post by Michael Blome (dated
June 26, 2003) for more information:
snip |
Good post Jeremy. I am going to take this up with my contacts at MS. It
is something that also inhibits my use of WM. I don't know if you'll get
anyone from MS to respond here. Unfortunately, most of the stuff I discuss
with them is covered by an NDA so it will be unlikely for me to be able to
report back what I learn.
--
1. If there are questions above, please answer them in-line. In any case,
don't top post. (Otherwise, don't expect a followup) See
http://tinyurl.com/22ubu
2. Remove this signature from your response if your newsreader isn't
intelligent enough to do it.
3. Common courtesy is to followup if someone helped you or if you found a
solution on your own. |
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