[Live-devel] About transfer of RTP / RTCP

[吉原正信]

live555 Dear Developer

I am promoting the development of stream transfer system
and I plan to use live 555.
I have some questions but please check one by one.

I am developing a relay system for stream data. Transfer
RTP / RTCP packets from the IP camera connected via Ethernet
to the receiving system. Transmission system and reception system
are wireless communication and unidirectional communication.
The software interface of wireless communication is a unique
interface (hardware access) without using socket.
Only IP and port number need to be changed and transferred.

I confirmed the source of "testRTSPClient.cpp".
The DummySink class was able to acquire media data,
but there was no RTP header.
I think that it is probably because the source class
is automatically specified as an appropriate class.

Next I confirmed the source of "testRelay.cpp".
I do not use the BasicUDPSink class on my system,
but I think that you can create your own class derived
from the MediaSink class.
In that way, we think that we can change IP packet to only
the destination, destination IP and port number and transfer
it to the receiving system.

Is this idea correct?

Please answer and give advice.


------------------------------------------------
Masanobu Yoshihara
Nippon Information Development Co., Ltd.
TEL: [phone]
FAX: [phone]
E-mail: ***@nid.co.jp
URL: http://www.nid.co.jp/
------------------------------------------------

[Ross Finlayson]

Post by 吉原正信
I am developing a relay system for stream data. Transfer
RTP / RTCP packets from the IP camera connected via Ethernet
to the receiving system.

First, do you know about our “LIVE555 Proxy Server”: http://www.live555.com/proxyServer/ ? It might already do what you want.

Post by 吉原正信
I confirmed the source of "testRTSPClient.cpp".
The DummySink class was able to acquire media data,
but there was no RTP header.

That’s correct. This is because we implement the RTP/RTCP protocol ourself, so applications do not need to see the header.

Post by 吉原正信
Next I confirmed the source of "testRelay.cpp".
I do not use the BasicUDPSink class on my system,
but I think that you can create your own class derived
from the MediaSink class.

If you wish to transmit the relayed packets as RTP packets, then you should use a “RTPSink” subclass, *not* a “BasicUDPSink”. (You should also send RTCP packets, by creating a “RTCPInstance” object.)

But once again, you should check whether our “LIVE555 Proxy Server" already does what you want.


Ross Finlayson
Live Networks, Inc.
http://www.live555.com/

[Masanobu Yoshihara]

Ross-san

Thank you for your quick answer.
I will ask again.

But once again, you should check whether our ?LIVE555 Proxy Server"

already does what you want.

Thank you for providing the information.
However, I think that detailed specifications have been decided and can
not be used.


Our system is a transmission system to which an IP camera is connected
and
a reception system to which a viewer is connected.
IP camera and viewer are connected via Ethernet respectively.
The sending system and the receiving system are unidirectional
communication (wireless).


My development part does not include IP cameras and viewers.

The transmission system has the following requirements.
- Function as an RTSP client for IP cameras
- Transfer RTP / RTCP packets from IP camera to receiving system
- RTCP (RR) transmission to IP camera
- Send the media information of the IP camera to the receiving system
with its own protocol

If you wish to transmit the relayed packets as RTP packets, then you

should use a ?RTPSink? subclass, *not* a ?BasicUDPSink?. (You should
also send RTCP packets, by creating a ?RTCPInstance? object.)

I understand that it is necessary to use the RTPSink subclass also to
use RTCP.
Is the source class OK by using the RTPSource subclass?

Just transfer it without being conscious of media format and audio /
video.


I may ask you about the receiving system at a later date.
Reference system requirements are as follows
- It acts as an RTSP server for the viewer (information is received
from the sending system with its own protocol)
- Transfer RTP / RTCP packets from the sending system to the viewer



Please answer and give advice.

----- Original Message -----

live555 Dear Developer
I am promoting the development of stream transfer system
and I plan to use live 555.
I have some questions but please check one by one.
I am developing a relay system for stream data. Transfer
RTP / RTCP packets from the IP camera connected via Ethernet
to the receiving system. Transmission system and reception system
are wireless communication and unidirectional communication.
The software interface of wireless communication is a unique
interface (hardware access) without using socket.
Only IP and port number need to be changed and transferred.
I confirmed the source of "testRTSPClient.cpp".
The DummySink class was able to acquire media data,
but there was no RTP header.
I think that it is probably because the source class
is automatically specified as an appropriate class.
Next I confirmed the source of "testRelay.cpp".
I do not use the BasicUDPSink class on my system,
but I think that you can create your own class derived
from the MediaSink class.
In that way, we think that we can change IP packet to only
the destination, destination IP and port number and transfer
it to the receiving system.
Is this idea correct?
Please answer and give advice.
------------------------------------------------
Masanobu Yoshihara
Nippon Information Development Co., Ltd.
TEL: [phone]
FAX: [phone]
URL: http://www.nid.co.jp/
------------------------------------------------