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#151
Originally Posted by bocaJ View Post
I'm sorry, I normally consider myself pretty tech-savvy, but could someone explain what "access arbitration" is, how it relates to this discussion and what it has to do with my future N900 dying in a fire?
The DSP (Digital Signal Processor) in the N900 is ensentially a co-processor which handles the chores of decoding video and sound streams (in this context). It's very much more efficient then having the main CPU do the same chores. But there is only one DSP and there isn't standard driver/process which controls access to it. That's the access arbitration that's needed.

The dying in a fire it more a metaphore of overdriving the DSP which might led to a catastrophic chip failure. In the past very extreme failures of chips have been the chip literal catching on fire. It's very doubtful the N900 could literally get that hot. Well unless the LION battery went kablooey.

Last edited by sljonson; 2009-12-02 at 18:35.
 

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#152
Originally Posted by zaheerm View Post
The dsp would error out on one or the other if it failed. This would happen if multiple gstreamer based processes used it too, so no different. I don't mind only having GStreamer but if others want mplayer/vlc let them do the work to get the dsp stuff working.
I vaguely recall some rumors that this would rather cause a device reboot than a mere failure of GStreamer, although I never checked (I wouldn't even know how to do that quickly). But even in the latter more optimistic scenario, we should expect quite nasty usability problems and bugs.

Also, I would not be surprised that the DSP would have some further limitations of its own.

Last, if the DSP can decode it, then gstreamer can decode. Then I don't know if there is much added value for DSP on Mplayer or VLC. Then it might be difficult to find a motivated, skilled, and free enough person to do the work
 
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#153
Originally Posted by bocaJ View Post
I'm sorry, I normally consider myself pretty tech-savvy, but could someone explain what "access arbitration" is, how it relates to this discussion and what it has to do with my future N900 dying in a fire?
Access arbitration just means a way of mediating or dealing with multiple users of a common resource. The implication here being that if two different media apps try to use the dsp at the same time, the overload and/or collision between data streams would cause harmful effects. Whether that's a realistic concern or hyperbole (exaggeration), i don't know.
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#154
Originally Posted by redenisc View Post
Last, if the DSP can decode it, then gstreamer can decode. Then I don't know if there is much added value for DSP on Mplayer or VLC. Then it might be difficult to find a motivated, skilled, and free enough person to do the work
Well, the reason I'm interested is that VLC's streaming capabilities have been more mature than gstreamer's on the last few versions of Maemo.

Perhaps this is changing, however. I notice that gstreamer now has an http sink available, although I haven't attempted to use it yet...
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#155
Originally Posted by qole View Post
Well, the reason I'm interested is that VLC's streaming capabilities have been more mature than gstreamer's on the last few versions of Maemo.

Perhaps this is changing, however. I notice that gstreamer now has an http sink available, although I haven't attempted to use it yet...
if you need streaming, i have flumotion working on the n900 and that uses gstreamer and python and twisted. i am porting the UI to be hildonised. if you want i can push a non hildonised pkg to extras-devel
 

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#156
well the thing about vlc is that you can stream any media

even iptv or satellite tv to your device and transcode it on its way before it hits the device with udp,http,rstp or whatever you like

and that is what is rocking vlc that you can stream in anyway you like
 
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#157
zaheerm: flumotion will be a killer app for Maemo. Looking forward to seeing your work.
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#158
Originally Posted by qole View Post
zaheerm: flumotion will be a killer app for Maemo. Looking forward to seeing your work.
Just vlc with a good GUI would be enough, but from what I can see flumotion looks quite promising.
 
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#159
I've gotten some flv's to play after getting the extra codec package, but I still have videos that don't play. And some were downloaded using my various Symbian devices, and they played just fine. But my device has been acting funny, so maybe it was the firmware. I'm reflashing as we speak. Hope it works out ok.
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#160
fixed! reflashing rocks
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