[Linphone-developers] problems in streaming on WAN for linphone ported on TI DM365

[Abhishek Ranjan]

HI all,

We are using linphone source for our SIP phone development on TI DM365 SOC. I have written filters for video encoding and decoding which uses TI's hardware encoder and decoder chip for video enc/dec operation and the rtp stack I am using as is. The audio part is same as present in linphone wiht G711 codec.

For video My graph is very simple:

cap_enc filter------> rtpsend

rtprecv----------------->decode_display filter

where cap_enc and decode_display filters are developed by us.

We have successfully tested the sytem in LAN (Local Area Network)conditions where there is no limit on upload/download speed.and we have absolutely no problems in LAN testing conditions. But we are facing issues while making calls on WAN via proxy. We are getting video in only one direction. But nothing in other direction. The issue we are facing is linphone is not able to send RTP packets on other side. 

-- Our test set up consist of one unit connected to 1 Mbps broadband and the other one to a 2 Mbps leased line connection.

-- The video resolution we are using is 4-CIF

-- tried to experiment with jitt_compensation but nothing happened other than increase in delay

-- Also tried to increase the video compression by relaxing the quantization parameter..

-- The video decode and display is successful on the unit which receives the call and this is consistent all the time. We dont get any successful decoding and display on the unit making the call.

-- RTP statistics showing that no of rtp packtes successfully delivered to the application is very low compared to the total number of packets received. 

Any suggestion on what could possibly go wrong while switching from LAN to WAN.

Thanks,

Abhishek Ranjan