[vlc] Re: upd stream buffering

[Albert Marti]

On 7/12/06, Jean-Paul Saman <jean-paul.saman at planet.nl> wrote:
>
> Albert Marti wrote:
> >
> >
> > On 7/12/06, *Jean-Paul Saman* < jean-paul.saman at planet.nl
> > <mailto:jean-paul.saman at planet.nl>> wrote:
> >
> >     Michael Chan wrote:
> >      > Dear all,
> >      >
> >      >   What if I have a network that can provide a 1GB capacity and
> assume
> >      > that the PC I/O port is fast enough to transfer the stream to
> decode
> >      > module?  Can I reduce the buffer in such situation?
> >      >   Besides, Is the capture from video signal (said video capture
> from
> >      > 1394 input) also follow the same behaviour?  I test that there
> are 1
> >      > second delay from the video cam to the display in my pc.  Anyway
> to
> >      > reduce the delay?
> >     Use another value for --dv-caching=10000, for instance. However
> since
> >     1394 sends data at 400 Mbps over the link, you need a really _fast_
> PC
> >     (>2GHz CPU) or LARGE buffer to not drop data at the input.
> >
> >     Gtz,
> >     Jean-Paul Saman.
> >
> >      >
> >
> >     --
> >     This is the vlc mailing-list, see http://www.videolan.org/vlc/
> >     To unsubscribe, please read
> http://www.videolan.org/support/lists.html
> >
> >
> >
> > I guess that this buffer is needed because the CPU needs enough time to
> > process all the packets. I guess also that this buffer has a minimum
> > safe value to work with a medium fast PC.
> >
> > Then, without having any knowledge about the VLC code/architecture,
> > could be possible to modify this buffer to a small value, recompile VLC
> > and run it on a really _fast_PC to reduce this latency?
> >
> > Has this any sense?
>
> You don't need to recompile for adjusting buffers in vlc. Just use the
> modules caching option. For input DV you need --dv-caching=<value> for
> file input --file-caching=<value>, for UDP input --udp-caching=<value>,
> etc.
>
> On the stream output chain it is the same. For UDP out adjust
> --sout-udp-caching=<value>
>
> Hope this helps.
>
> Gtz,
> Jean-Paul Saman.
>
> --
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>
>
As I mentioned before I already adjusted those parameters in the server
(--sout-upd-caching 0) and in the client (:udp-caching=0) without any
result.

I'm guessing because there is always a minimum buffering that vlc is doing
internally (at level of code)

I guess also this buffering is done to give some time to the CPU to process
the stream.

My question was regarding that internall buffering, if modifing the code, an
assuming that you run VLC in a really fast pc, would work.


Is it clear enough?

Thanks

ALbert
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