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mwalker29
03-31-2010, 05:57 PM
Hi all. Please let me know what you think.

Our tricaster gets used multiple times daily and it usually always on. So we are really getting it for all it's worth.

Recently it has started to lag. After we stream a video we watch it and it is starting to record 25-40seconds after we click the button. We are using ustream.

Please give me some advice here, the tricasters daily use is crucial to us.

Thank you for you help.
Cameron

mwalker29
04-01-2010, 10:59 PM
Anyone?

ACross
04-05-2010, 07:11 PM
I am afraid that the amount of latency that you are reporting with live streaming sounds about normal. Unfortunately this is caused by both the server and the player end of things, much more than the TriCaster itself.

mwalker29
04-05-2010, 09:29 PM
There cant be this much lag. And not only is there this much lag but it is so inconsistent.

Is there any way to get this lag to either be more consistent or to get rid of it in general?

Thanks

ACross
04-05-2010, 09:45 PM
There cant be this much lag. And not only is there this much lag but it is so inconsistent.
Is there any way to get this lag to either be more consistent or to get rid of it in general?
Thanks

The reason that it is so inconsistent is that the vast majority of it is occurring on the browser side of things. If you think when you press the "play" button in the player, the embedded player in the browser typically buffers for several seconds, those seconds are the latency that are going to occur. These are meant so that if there are "hickups" int he bandwidth available between the player and the server that video is not interrupted.

Finally, remember that streaming video is typically heavily compressed in a format like H.264. This means that there are probably several seconds between I-Frames, which means that both the encoder and decoders are going to need at least this much latency to play back the file.

If you run and administer your own server then there are some settings that you can use that give "recommendations" to players as to how much buffering to use and these will probably bring it down quite a lot (although it will still be several seconds.)

There are some streaming protocols designed specially to achieve much lower latency (see video conferencing systems) however this is almost always at a significant cost in video quality.

Andrew

mwalker29
04-05-2010, 10:08 PM
Understood and thank you for your help Andrew. Right now I am actually using the tricaster to make videos that goto a "server", but I am just using the flash file saved locally and uploading it to another server in which clients can watch the videos. If that makes sense at all. So I am not doing any live streaming.

So the issue is, when I am recording, if I do not wait long enough to being the video after clicking stream, it does not record the beginning of the video.

It is frustrating because there is no way for me to see when the tricaster has actually begun recording until I am finished filming.

Thank you again for your help

ACross
04-05-2010, 10:21 PM
I think that we where talking about different things. I think that your issue is slightly different from what I was responding to above. Basically what happens when you click "stream" is that Flash Media Encoder will try to connect to a remote site and when it times-out it will then start to record locally and continually try to reconnect to the site continuously.

One potential work-around (which might not work) would be to specify a local IP address as the streaming destination so that the initial timeing out occurs much more quickly.

Andrew

mwalker29
04-05-2010, 10:32 PM
Give me some more info on that if you can.

I do not use the tricaster to stream anything live. But to make flash videos that I put on a server to stream later. So I have it set to goto a real server, but I do not ever use that server for anything but to point tricaster to

ACross
04-05-2010, 10:36 PM
Give me some more info on that if you can.
I do not use the tricaster to stream anything live. But to make flash videos that I put on a server to stream later. So I have it set to goto a real server, but I do not ever use that server for anything but to point tricaster to

Why do you not just use regular recording in TriCaster, and then transcode the files for use on a media server ?

mwalker29
04-05-2010, 10:39 PM
It takes longer to encode than just using realtime with streaming. Plus once they are flv files, I send them to encoding.com to be encoded into 6 different types of streams.

bob anderson
04-06-2010, 04:32 PM
I believe you can use the Localhost as your server, and not have to stream to a server that's not doing anything.

I believe I'm getting the question you are asking a bit more clearly than Andrew. I think what you are saying is, when you hit that stream button, you are expecting the recorded result to start from the point you hit the button, but you are experiencing a period of time from the time you hit the button, to when the actual results start. In effect this requires you to hit record, and have a slate up for 30 seconds before your actual live action can commence in order to compensate for this delay in the recording actually starting.

I've never seen this happen before and have no explanation, nor fix, so hopefully Andrew is still monitoring this and can enlighten us all!

Bob Anderson

mwalker29
04-06-2010, 04:48 PM
Thanks bob. We will wait for Andrews response.

ACross
04-06-2010, 06:58 PM
Thanks bob. We will wait for Andrews response.

I am afraid that I did understand correctly ... The stream option is primarily designed for streaming to the web and not as a compressed recording capability, as such it does try to connect with a streaming server when you press the "stream" button, and the negotiation (or lack thereof if you enter in a server that does not exist) can take a few seconds.

This behavior is actually not directly our code, but rather Flash Media Encoder that we rely on to ensure high quality and compatibility streaming. I do believe that entering localhost as the server might help somewhat, although I do not expect using streaming as a recording replacement would give you the same level of recording performance as the record capability would.

Andrew

mwalker29
04-07-2010, 12:01 PM
So there should be no delay in when it start recording input. Do you have any suggestions to get rid of this other than using localhost?

ACross
04-07-2010, 01:19 PM
So there should be no delay in when it start recording input. Do you have any suggestions to get rid of this other than using localhost?

I am afraid you are using the "stream" option for something that it was not really designed for, and so I do not know of a solution that would give you exactly what you need. Indeed, I believe that even outside of the TriCaster, Flash Media Encoder itself would not be capable of starting a recording without any initialization delay.

Andrew

mwalker29
04-07-2010, 02:48 PM
Yes and I agree. But 20-30 seconds seems a bit excessive.

Not trying to argue. I really do appreciate your help.
Thanks
Cameron

ACross
04-07-2010, 04:06 PM
Yes and I agree. But 20-30 seconds seems a bit excessive.

I actually totally agree with you. Having looked at what is happening however, this time is being spent by the Adobe Flash encoder, which we have no direct way of controlling.

A.