[MPlayer-users] asf mmst streaming problems

[Stephen Stocker]

>Hello,
>
>I've been trying to regularly "download" (dump to disk) WMV3 streams
>off a website; here are a couple of example commands that i'm calling:
>
>mplayer -noframedrop -dumpstream -dumpfile "Daily Show - 2005.09.21 -
>Stewart - Closer Look - Press Secretaries.wmv"
>mms://a874.v99506.c9950.g.vm.akamaistream.net/7/874/9950/v001/comedystor.downlo
>ad.akamai.com/9951/com/dailyshow/jon/jon_10119.wmv
>
>mplayer -noframedrop -dumpstream -dumpfile "Daily Show - 2005.09.21 -
>Celebrity Interview - Ricky Gervais.wmv"
>mms://a1740.v99506.c9950.g.vm.akamaistream.net/7/1740/9950/v001/comedystor.down
>load.akamai.com/9951/com/dailyshow/celeb/celeb_10119.wmv
>
>Frustratingly, my downloads are frequently fail. Mplayer falls over
>with the following message:
>
>read error:: Invalid argument
>pre-header read failed
>Core dumped ;)
>
>I tracked this message down in the code to
>libmpdemux\asf_mmst_streaming.c
>
>I poked around further and hypothesised that the error has something
>to do with a dropped connection to the server. I then tested a hunch
>by repeating my download and disabling my network connection during
>the process. And presto, I got the same message, and upon repeating it
>I got the message:
>
>read error:: Invalid argument
>media data read failed
>Core dumped ;)
>
>(which is from the same function in the code).
>
>This all probably makes sense, because my internet connection is a bit
>dodgy: it's shared amonst many people and also it's through a proxy;
>as a result, it must drop out periodically.
>
>As a result of this "adventure", I have several requests/bug reports to make:
>1) Is it possible to make the error message less cryptic? Users
>shouldn't really have to dig through the source to figure out the
>meaning of errors.
>
>2) These streams that I'm using are diagnosed as "not seekable".
>However this isn't the case as windows media player (and other
>programs) have no problems resuming from the failure point in the
>video stream when the connection is dropped. If the streams could be
>made resumable under MPlayer, then interruptions would not be so bad,
>in the sense that the dumping could just proceed from that point, and
>wouldn't have to be started again.
>
>3) If while viewing one of the above URLs, the user tries to seek
>forward, Mplayer crashes.
>
>The "-v" output is included below. I'm running an AMD Athlon64 3000+
>S939 under WinXP SP2; these problems manifest themselves under the
>latest CVS build.
>
>Regards,
>
>Jake Benilov
<snip>

  Hi,

  The "Stream not seekable!"  is normal, for most streams, and the "Core
  dumped ;)" tells you only that it's finished (a joke the developers
  slipped in :)).

  If you check, you should have a file with the name you used for
  -dumpfile. In the first case, the file contains these URLs (among
  other things) :
  
http://a1437.v99506.c9950.g.vm.akamaistream.net/7/1437/9950/v001/comedystor.download.akamai.com/9951/com/dailyshow/jon/jon_10116.wmv
http://209.170.79.203:80/7/1437/9950/v001/comedystor.download.akamai.com/9951/com/dailyshow/jon/jon_10116.wmv

  I had to trim some junk at the end of the URLs to get it to work, but
  that should do it. I hope this makes sense, I'm running on too little
  sleep. :)

  Take care,
  Steve