[FFmpeg-devel] [PATCH] oggpagesize option added

[Baptiste Coudurier]

Hi Gregory,

On 01/26/2011 01:11 PM, Gregory Maxwell wrote:
> I think this is a pretty poor solution for the stated problem. It
> would basically be copying the braindead behaviour we're stuck with in
> libogg because of some poorly thought out parts of our ABI.
>
> The fundamental issue here is that more tightly packed pages mean
> greater efficiency, but they also mean higher delay. If you don't care
> about delay? pack away. But if you care then you have issues.
>
> The reason this solution is not good is that a straight size limit
> does _not_ bound the delay very tightly. If the packets being emitted
> by the codec are very small then you can still get up to 255 of them
> in a single page? which is the same worst case delay you had with
> maximum size pages!   This means that your delay bounded streaming app
> will mostly work, but if the bitrate drops down it will stall and
> rebuffer.
>
> The _correct_ behaviour is to decide how much delay you are willing to
> tolerate and flush at least that often? regardless of how much data is
> in the pages.   Gstreamer does this.  Ffmpeg2theora also has a cap on
> the number of packets it will attempt to place per page.

I definitely agree with this and implemented something like this in the 
past.

Anyway with the per muxer options, it's easy to add.

[...]

-- 
Baptiste COUDURIER
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