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Hi, <br>
<br>
today, i've been trying sucessfully a first link :<br>
webcam plugged on a server (ubuntu-server 10.04 LTS). / 1 customer
windows XP using VLC<br>
<br>
I had many difficulties to obtain the stream on VLC.<br>
in many other configurations, ffmpeg was freezing after a while, for
example using mpeg2 and mpeg4 codecs<br>
Also ogg format did not give me good results.<br>
<br>
<br>
Finally I could only get it working using :<br>
format = swf<br>
videocodec = flv <br>
(no audio used at this moment).<br>
pictures are 352x288 15fps<br>
bandwidth used 150Kbits-500Kbits (depending of the content of the
movie)<br>
<br>
<br>
ffmpeg is succesfully launched from ffserver<br>
ffmpeg -s cif -f video4linux2 -i /dev/video0 -r 14 -g 10 -vcodec flv<br>
<br>
I can see a delay of approx. 6-7 sec between an action and seeing the
result on the screen.<br>
<br>
So my question is : <br>
is it possible to reduce this delay ?<br>
<br>
ffmpeg is making and encoding...<br>
... but I wonder if ffserver is (also) making another
decoding/re-encoding ? This could be a reason of soo much delay
(because of the GOP).<br>
<br>
So I wonder if I could reduce this delay by passing raw images from
ffmpeg to ffserver ?<br>
(for the moment I try it , unsuccessfully)<br>
<br>
<br>
Or is just ffserver streaming exactly what it receives ? So what is the
reason to declare to (video/audio)codecs in ffserver conf-file ?<br>
<br>
<br>
best regards,<br>
<br>
<br>
<br>
Le 08/03/2012 11:30, nandan amar a écrit :
<blockquote
cite="mid:CAExv3aJshTxo5jkM59DQ87-UoZ56--z84uAD7KgqaYQKpQWT_Q@mail.gmail.com"
type="cite"><br>
<br>
<div class="gmail_quote">On Thu, Mar 8, 2012 at 3:50 PM, informatique
lycee Pays-de-Retz <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:adminrezo.0441992b@ac-nantes.fr">adminrezo.0441992b@ac-nantes.fr</a>></span>
wrote:<br>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">hello,<br>
<br>
I am looking for a technical solution to make live video-streaming to<br>
many users (almost) simultaneously<br>
<br>
Because of the risk of traffic-jam on the connexion-link of the server,<br>
my idea so solve this risk is to create a cascaded architecture :<br>
<br>
- 1 video-station is sending initial stream to 1 top-level-server<br>
- 10-30 2nd-level servers get the stream from the top-level server :<br>
act as relay-server<br>
- 20-50 3rd-level servers receive the stream from every second-level<br>
server (this makes 30 x 50 = 1500 servers) : act as relay-server<br>
- customers are on the 4rth level : about 100 customers per 3rd-level
server<br>
<br>
second-level and third-level servers are on ADSL connexions<br>
<br>
so I have 3 questions :<br>
1) level 1 : do ffmpeg and ffserver necessary have to be on the same<br>
computer ? or is it possible to put a network-link between those 2<br>
applications ?<br>
</blockquote>
<div><br>
</div>
<div>Yes This is possible.</div>
<div>You can feed video stream to ffserver as :</div>
<div><span
style="color: rgb(86, 85, 85); font-family: 'courier new',monospace; line-height: 24px; background-color: rgb(255, 255, 255); font-size: medium;">ffmpeg
-i <input_video_file>
<a class="moz-txt-link-freetext" href="http://">http://</a><server_address>:<port_no_where_server_is_listening>/<file.ffm></span> <br>
</div>
<div><br>
</div>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">2)
level 2 and 3 : is it possible to build this cascade architecture<br>
with ffmpeg and ffserver ? that means create relay-servers based on<br>
ffmpeg and ffserver ?<br>
<br>
</blockquote>
<div>This looks like bit difficult and may not be possible as
ffserver needs feed in advance.</div>
<div>So cascading may work but delay may be an issue.</div>
<div> </div>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">3)
what is the best and reliable encoding for this (video 352x288<br>
10-15fps + audio 10 kHz) ?<br>
<br>
Thanks for any technical help<br>
<font color="#888888"></font></blockquote>
<div><br>
</div>
<div> what is your streaming media type.</div>
<div>If it is normal movie 25 fps sud work and CIF (352x288) for not
so great as HD kind of quality. </div>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><font
color="#888888">
<br>
-- <br>
Xavier COUDIN - coordinateur informatique<br>
Lycée Pays-de-Retz, 44210 Pornic, gsm 06 80 28 40 53<br>
_______________________________________________<br>
ffserver-user mailing list<br>
<a moz-do-not-send="true" href="mailto:ffserver-user@ffmpeg.org"
target="_blank">ffserver-user@ffmpeg.org</a><br>
<a moz-do-not-send="true"
href="http://ffmpeg.org/mailman/listinfo/ffserver-user" target="_blank">http://ffmpeg.org/mailman/listinfo/ffserver-user</a><br>
</font></blockquote>
</div>
<br>
<br clear="all">
<div><br>
</div>
-- <br>
<div><br>
</div>
Amar Kumar Nandan<br>
Karnataka, India, 560100<br>
☎:+91-9019054471<br>
✉:<a moz-do-not-send="true" href="mailto:nandan.amar@gmail.com"
target="_blank">nandan.amar@gmail.com</a><br>
<a moz-do-not-send="true" href="http://aknandan.co.nr" target="_blank">http://aknandan.co.nr</a><br>
<pre wrap="">
<fieldset class="mimeAttachmentHeader"></fieldset>
_______________________________________________
ffserver-user mailing list
<a class="moz-txt-link-abbreviated" href="mailto:ffserver-user@ffmpeg.org">ffserver-user@ffmpeg.org</a>
<a class="moz-txt-link-freetext" href="http://ffmpeg.org/mailman/listinfo/ffserver-user">http://ffmpeg.org/mailman/listinfo/ffserver-user</a>
</pre>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Xavier COUDIN - coordinateur informatique
Lycée "Pays-de-Retz"
1 pl Joseph Girard 44210 PORNIC
tel 02 40 82 40 19 poste 167</pre>
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