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<p class=MsoNormal>Dear Live555 team,<o:p></o:p></p>
<p class=MsoNormal>I recently develop an application that uses live555 library
and operates simple tasks such as: get video data from camera, decode video
data, draw something on video frame, encode video frame and streaming. My
application is a client (to camera) and also a server when streaming video
data.<o:p></o:p></p>
<p class=MsoNormal>To get video data from camera, I modified the testRTSPClient
in testProgs. Data received then decoded using ffmpeg and drawn some text, shape
using Qt. After that, I use ffmpeg again to encode video frame (codec is
MJPEG-4) and put the output into a queue which will be streamed later.<o:p></o:p></p>
<p class=MsoNormal>To stream video from a queue, I write a class based on
DeviceSource, the function doGetNextFrame always read mpeg-4 package from queue
and calls FrameSource::afterGetting(this) when data available. I also write a
class called Mpeg4LiveServerMediaSubsession which subbed class from
OnDemandServerMediaSubsession and re-implement three virtual functions
(getAuxSDPLine, createNewFrameSource, createNewRTPSink). The createNewFrameSource
actually return the MPEG4VideoStreamDiscreteFramer::createNew() with input source
parameter is my class based on DeviceSource described above.<o:p></o:p></p>
<p class=MsoNormal>I use VLC as client to connect to my server and play video
stream. Everything seems ok and my application works quite fine when there are
less than 4 clients connect to server. When the 4<sup>th</sup> client connect
to server, the video of all clients is getting slower, image is very bad, I
cannot see video content clearly … <o:p></o:p></p>
<p class=MsoNormal>I don’t think the problem is with my network because I
use LAN with a good capable and even my server and client (VLC) in the same
computer, this problem still happens. <o:p></o:p></p>
<p class=MsoNormal>I have some more information here: <o:p></o:p></p>
<p class=MsoNormal>My processor : corei3 3.36 MHz, Memory (RAM): 4GB, When 4
client connect to server, program uses 30% of memory, 49% of CPU<o:p></o:p></p>
<p class=MsoNormal>When 1 client (VLC) connect to server, from VLC tool I see
that the content birate is about 6000 – 7000 kb/s. It reduce to 4000 –
5000 kb/s when 2 clients connect to server, 2000 – 2500 kb/s when 3
clients connect to server and 600 – 1500 kb/s when 4 clients connect to
server. <o:p></o:p></p>
<p class=MsoNormal>Do you have any ideals with my problem and any suggestions
to improve video quality when there are many clients connect to server? <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks!<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#0070C0'>Regards,</span></b><span style='font-size:10.5pt;color:black'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;color:black'><o:p> </o:p></span></p>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#0070C0'>Nguyen Van Long (Mr)</span></b><span style='font-size:10.5pt;
color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='line-height:13.5pt'><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:#7F7F7F'>ESoft - Software Development </span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif";color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='text-align:justify;line-height:13.5pt'><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:#BFBFBF'>-----------------------------------------------------------------------------</span><span
style='color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='text-align:justify;line-height:13.5pt'><b><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:#0070C0'>ELCOM
CORP </span></b><span
style='color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='text-align:justify;line-height:13.5pt'><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#7F7F7F'>Add:
Elcom Building, Duy Tan Street, Cau Giay District, Ha Noi</span><span
style='color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='line-height:13.5pt'><span style='font-size:8.0pt;
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<p class=MsoNormal><o:p> </o:p></p>
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