Max Bitrates relation to buffer size

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peter893
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Joined: Mon Feb 09, 2009 3:51 pm

Max Bitrates relation to buffer size

Post by peter893 »

Max Bitrates relation to buffer size:
Is there are relation? how do they relate? should a given max rate have any specific type of buffer amount?

Is a buffer needed when setting max bitrate anyway? Is buffer only related to streaming over networks?


Edit: opps should have posted this in Devices... please move mods...
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Rodeo
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Re: Max Bitrates relation to buffer size

Post by Rodeo »

peter893
Posts: 15
Joined: Mon Feb 09, 2009 3:51 pm

Re: Max Bitrates relation to buffer size

Post by peter893 »

Im still not understanding how buffer affects things.

Right now Ive figured that my Mac Mini 1.83ghz running Plex (.13) can handle around a MAX/Peak bitrate of 30mps.
So ive capped it vbv-maxrate=26000 and a bufsize=5000 and Ive set the average bitrate to 20000

Can someone that knows... explain what ive done here? lol and if this is a good idea/setting

Thank you
Last edited by peter893 on Thu Apr 23, 2009 1:52 pm, edited 1 time in total.
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Rodeo
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Re: Max Bitrates relation to buffer size

Post by Rodeo »

Have a look at the logs above. They're a bit technical (I don't fully understand them), but there's a lot of precise info about this feature…
peter893
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Joined: Mon Feb 09, 2009 3:51 pm

Re: Max Bitrates relation to buffer size

Post by peter893 »

Yes, thank for posting the link rodeo. I did read some of it. was looking for someone to expand on my follow up. thanks though...
dynaflash
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Re: Max Bitrates relation to buffer size

Post by dynaflash »

peter893 wrote:Im still not understanding how buffer affects things.

Right now Ive figured that my Mac Mini 1.83ghz running Plex (.13) can handle around a MAX/Peak bitrate of 30mps.
So ive capped it vbv-maxrate=26000 and a buffrate=5000 and Ive set the average bitrate to 20000

Can someone that knows... explain what ive done here? lol and if this is a good idea/setting

Thank you
Well, for how long ? a vbv buffer has to have a specified length. this has to be known to determine if you're settings make any sense.
peter893
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Joined: Mon Feb 09, 2009 3:51 pm

Re: Max Bitrates relation to buffer size

Post by peter893 »

dynaflash wrote: Well, for how long ? a vbv buffer has to have a specified length. this has to be known to determine if you're settings make any sense.
How long? you mean the length/time of the movie? can you type in an example?


thanks
dynaflash
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Re: Max Bitrates relation to buffer size

Post by dynaflash »

well, as the docs you were linked to explain, a video buffer has a size and a length. Not the length of the movie, but the specified length of the devices video buffer. You would get this from the specs or from *alot* of empiricle testing. Video buffer length might be .5 seconds, or one second or ??? basically you do not have enough info about the target video buffer to determine if your settings are sane or not. Its much more complicated than it looks.
peter893
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Joined: Mon Feb 09, 2009 3:51 pm

Re: Max Bitrates relation to buffer size

Post by peter893 »

I Did read the link, but I guess I didnt understand.

So the playback devices/softwares working buffer = the buffsize?

I have had no issue with the moveis Ive done with setting above... what would be some issues if incorrect bufsize was set?
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