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RTSP vs HTTP Video (was mesh overhead)

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w8erd
RTSP vs HTTP Video (was mesh overhead)
The topic I started as Mesh Overhead branched into other topics, so it was rightly suggested to start a new topic.
See Mesh Overhead for previous comments.

I made a test of rtsp vs http protocols over our local mesh network.
Connected to a station who is 5 hops away, and has a camera that supports rtsp and http. ETX 5.35.
There is no other traffic on the network except the usual overhead.
The camera is set to 30 fps (too high I know).  But in the past I have lowered it to 3 fps and it made no difference.
Connected with IE and Firefox via HTTP.
Connected with VLC via RTSP.   It seems to disconnect after several minutes; not sure.
Cannot make mplayer work with rtsp; shows just 1 frame and disconnects,
The net result is about 1/3 fps received here in all cases.

I understand that rtsp should generate less traffic since it is not expecting acks.
Should I expect better video performance with rtsp vs http, in this case?
Or would it make a difference only if the network were heavily loaded?  

Comments appreciated.

Bob W8ERD
AE6XE
AE6XE's picture
Bob,  

Bob,  

While most RTSP use RTP which uses UDP to stream the data, it's not a given.  Would have to confirm that your ipCam is indeed using UDP--probably a safe bet however.    RTSP is the control handshaking, as is HTTP and are both TCP based.    They might both be using udp when the video is streamed regardless.   What I usually do is run "tcpdump" on the mesh node to see the live packets--this tells all.   You can see when UDP sequence #s have gone missing.  You might also load wireshark on a windows or linux box and capture the packets where the video stream is arriving to.   

[update]   Ok, I did a quick sample of a playlist of live cameras I routinely see the weather in the area from.    I was surprised to find that the "rtsp" URL the camera's support, only 50% actually used UDP.   Summary:

Aircam:  TCP
Sumpple:  TCP
StarCam:  TCP
Foscam:  UDP
MegaPix: UDP
TrendNet:  UDP

I'll have to dig to see if a different formated URL yields a choice of TCP vs. UDP...

Joe AE6XE

w8erd
The camera I used is a
The camera I used is a Soleratec SNC-DM160.

Bob W8ERD
w6bi
w6bi's picture
Another RTSP/UDP Cam
I can confirm that the Hosafe Model 1MB1W IP Camera streams RTSP in UDP

Orv - W6BI
w6bi
w6bi's picture
VLC and flawed video streams
Our testing here revealed that VLC does not do well with less-than-perfect video streams.   If you watch its codec stats, it will continue to take in video frames, but stop updating the screen.    Mplayer seems to be more robust in that respect.

Orv W6BI
w8erd
RTSP vs HTTP Video
Sorry I am not savvy enough for wireshark or dumps.
I hate to buy a camera that is not as efficient as possible.  
Can someone recommend some specific good PTZ cameras that are known to do RTSP and UDP?
And what is the syntax to use them with mplayer and vlc?

Thanks!

Bob W8ERD
 
w8erd
TCP vs UDP Video
I have continued this investigation. I have been using Anycam, which is nice because if can do UDP and has camera control.
I have been working with their programmers. UDP can be turned on by editing a hidden config file, which they told me about.
Unfortunately the UDP video has occasional distortions which make it unusable. They are aware of this problem. In an attempt to fix it, they
connected to my PC and camera via Teamviewer many times, and made a number of software changes. Unfortunately they were unsuccessful and 
ultimately gave up.  So much for TeamViewer.

Usng wireshark, I discovered that VLC will do UDP by default with my KKmoon camera.  Unfortunately it does not do camera control

Is there any program that will do both UDP and camera control?

Thanks!
Bob W8ERD
w6bi
w6bi's picture
RTSP and camera control

We've standardized on Sunba IP PTZ cameras for our network.  They work well and RTSP (which I believe rides on UDP; correct me if I'm wrong) while a hassle to set up and work with, is very efficient at streaming video.   As you've pointed out, VLC understands RTSP, but doesn't do camera control.
The only camera control program I have experience with (other than the Sunba plug-in for IE) is the Happytime ONVIF Client .  The current version works, but is a bit buggy.

Hope this helps.

Orv W6BI

w8erd
Happytime ONVIF
This program sounds very promising Orv. Thanks!
Unfortunately I cannot make it work because it complains about missing dll files.
There are a number of web sites which claim to fix these errors, and I have tried many of them
without success. They just don't work or they are dangerous.  So I have given up for now.

Bob W8ERD
 
w8erd
Happytime ONVIF
I FINALLY  made this work after MUCH finagling with wrong web sites etc.
Basically:
1.Make sure Directx is installed and working.
2. Search the Internet and find the 2 dll files it says are missing.
3.Copy them into the folder
     c:
     windows
     syswow64 (assuming you have a 64 bit PC).
4. Restart PC
5.Voila!
 
BUT it is not as useful as I had hoped. I was hoping it was ONLY an ONVIF client,
that could simply control a camera.  Unfortunately it is ALSO a full fledged video client,
which uses TCP.  It is a GOOD client, with the least latency of any program I have seen.
 
So I still do not have any way to run a minimum traffic UDP viewer program, and also control the camera.
I suppose one could temporarily start a different viewer in parallel with VNC, just to steer the camera occasionally.
Many other programs exist, including web browsers.
 
Bob
 
AE6XE
AE6XE's picture
I used happytime onvif for an
I used happytime onvif for an event with 6 ipCams a while back. I found there was a lag of 10 sec or more on the video as compared to a direct browser access. The lag time was problematic when trying to control the camera. The delay to PTz the cam made it extremely difficult to track anything. I ended up buying a progam. Joe AE6XE

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