Can WMP 9.0 play back a third party encoded ASF?

Discussion in 'Windows Media Player' started by wutheringhouse, May 18, 2004.

  1. Can WMP 9.0 play back a third party encoded ASF?
     
    wutheringhouse, May 18, 2004
    #1
    1. Advertisements

  2. If a DirectShow-compatible decoder is installed, it should.
    That is a VCM codec, a DirectShow transform filter or a DMO.

    --

    /**
    * Alessandro Angeli
    *
    * MVP :: Digital Media
    *
    * a dot angeli at biosys dot net
    */
     
    Alessandro Angeli [MVP::DigitalMedia], May 18, 2004
    #2
    1. Advertisements

  3. But Why WMP 6.4 can play it when WMP 9.0 can't play it back?
     
    wutheringhouse[DR.], May 18, 2004
    #3
  4. WMP6.4 uses the old WMSourceFilter and WMP9.0 uses the new WMASFReader. They
    do not behave in the same way. But they both should support custom codecs.
    You can try to simulate WMP9.0 in GraphEdit or in code by manually inserting
    the WMASFReader in an empty graph, make it load your test stream and render
    its output pins, so you can try to figure out what's going on inside WMP
    (and maybe provide some useful error code or debug info). Also, how is your
    decoder implemented? DMO, VCM codec, DS filter...

    --

    Alessandro Angeli

    MVP::DigitalMedia

    a dot angeli at biosys dot net
     
    Alessandro Angeli [MVP::DigitalMedia], May 18, 2004
    #4
  5. When i insert the WMASFReader or WMSourceFilter into a GraphEdit,and open my
    asf file ,the GraphEdit can work on.When I Use WMP9.0 to play it , WMP9.0
    give a message box: can't find a XXX codec.
    I wonder that Whether must have a decode DMO to Play a third encode ASF with
    WMP 9.0.But i have only a decode DS filter.
     
    wutheringhouse[DR.], May 18, 2004
    #5
  6. Does ASFViewer show the correct BITMAOINFOHEADER data in the ASF?

    http://www.microsoft.com/windows/windowsmedia/format/ASFViewer.aspx


    --

    Alessandro Angeli

    MVP::DigitalMedia

    a dot angeli at biosys dot net
     
    Alessandro Angeli [MVP::DigitalMedia], May 18, 2004
    #6
  7. When use ASFViewer to open my ASF file,the info is showed as follows:
    Bitmap Info Header
    biSize 40
    Width 352
    Height 288
    Planes 1
    Bits 24
    Compression TEXT: JML2
    0000: 4A 4D 4C 32 JML2
    Image Size 0
    X Pels / Meter 0
    Y Pels / Meter 0
    Colors Used 0
    Colors Important 0
    Error Concealment
    Strategy No Error Correction


    Is it correct?
     
    wutheringhouse[DR.], May 19, 2004
    #7
  8. It looks OK to me but you only know what it is supposed to be.

    When you render the file in GraphEdit, what does you graph look like? Does
    it contain any ColorSpaceConverter, AviDecompressor, OverlayMixer...? What
    video renderer does it contain? This last one is tricky: open up its
    property page to see whether it is a VMR7, VMR9 or old VR.

    --

    Alessandro Angeli

    MVP::DigitalMedia

    a dot angeli at biosys dot net
     
    Alessandro Angeli [MVP::DigitalMedia], May 19, 2004
    #8
  9. When i render the file in GraphEdit,the graph is showed as follow:
    myfile.asf-> my Decompress filter-> Color Space Conventer-> VMR7/old VR
    -> Mpeg Layer-3 Decoder -> Default DSound Device
    Now i can't make sure that only by a decoded DMO is registerd can play a
    third party encoded ASF?
     
    wutheringhouse[DR.], May 20, 2004
    #9
  10. What ASF source filter is that? The old Windows Media Source
    Filter or the WM ASF Reader. You should use the latter.

    What video renderer did you actually use, the VMR7 or the
    VR? You should make sure it's the VMR7

    What color space does your filter output in? And what
    conversion is the CSC doing?

    I'm asking because WMP9 uses the WMASFReader and the VMR7
    and the presence of the CSC may be the problem since I think
    WMP9 inserts some hidden transform filter or forces the use
    of a specific color space in order to provide color
    correction controls.
    If it is this way, it is not documented. But it should not
    be since older WM decoders were WMM codecs.

    --

    /**
    * Alessandro Angeli
    *
    * MVP :: Digital Media
    *
    * a dot angeli at biosys dot net
    */
     
    Alessandro Angeli [MVP::DigitalMedia], May 20, 2004
    #10
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.