Is 'real' time possible? (or almost)

[username]

Hi,
I've gotten this streaming setup to work more or less (except for VP6(.2)) but now I see that no matter what I do, there is a lag of about 5 seconds at minimum in the video transmission. I am watching it on the exact same computer as I'm encoding it, yet it will simply not play in realtime. Its encoding a live stream from the capture card, but it seems that the player is saying 'I need at least 5 seconds of data before I'll show him a picture. I dont want to be caught without a feed at any given moment'

In truth, I dont care about the the quality nearly as much as I care about the 'liveness' of the feed- ie when the camera moves, so should the picture. It shouldnt wait 5-10 seconds before it catches up to that move...

Any ideas/info?

Thanks,
Larry

PS- The preview is correct and realtime, its just that the video output on the player is lagging behind as though I were viewing it in Russia...

[ken52787]

That is the buffer. Shoutcast uses this to provide QoS (quality of service). There is nothing you can do about it. If you are looking for true real-time, shoutcast/nsv is not the solution.

[username]

Then what is? I'd like to have almost true real-time embedded in a website... What options are there?

[slavas]

u can try to search / write yourself sc replacement with lower buffering

[username]

Sorry but I dont understand that- what does that mean in English?? (I dont have too much experience in this field)

EDIT: I just did a little experiment and it seems that the feed is almost a full ten seconds ahead of the live stream. :( (I just did some changes in the sttings and its down to five second delay- but why cant it be realtime especially on the same computer?!)

[DjDemonD]

Simple really its about the reliability of the connection between your source (camera) and the output (monitor).

The most reliable connection is a good old fashioned cable between camera and monitor. This will provide realtime video and is very reliable the cable is only subject to being damaged and interferance from radio frequency.

Now when you move onto using the internet as a way of connecting your camera and your monitor you run into a host of problems.

The amount of data a standard broadband internet connection can send and receive is very small really. Compared to a good old fashioned cable its very small indeed. Also the internet is not realiable its subject to connections being slow, to the connection being overloaded by lots of data moving etc...

To keep a stream of audio or video smooth the receiving computer must display the data with a delay. If the connection slows down or stops for a short time the buffer (a bit of memory which stores the data for a time before displaying it) keeps the data flowing. When the connection comes back to normal speed the buffer is filled up again. The upshot of which is that your video stays smooth even though really its being sent information which can be very patchy.

If you were to set the buffer to 0 you would have realtime video until your internet connection slows down or stops (this happens all the time) your video would then stop or jump around and be very hard to view indeed.

We broadcast audio (and soon video) it doesnt matter to our audience if there is a delay they really dont care its not important they get a smooth (for the most part) audio signal without any skips or gaps due to the buffer.

If you want to broadcast on a more reliable network or the same computer in real time youll need a technology not designed for the internet which doesnt have to cope with these connection problems.

[username]

Thanks for the explanation. But now I dont understand how ppl can do video conferencing, being that one needs some sort of audio/video sync and 'realtimeness'...?! If they use another type of streaming method, then maybe I should just use that... Any ideas about this?

THanks

[Inedible Bulk]

That's just silly.

Ever watch tv where they're communicating with someone 'via sattelite' ? it's obvious there's a 3 second lag both ways.

[username]

But a five second delay when I'm broadcasting to my own computer?? I dont get it. I tried setting all buffers to 0 but it changes them to 100 automatically (which is probably one second, but it doesnt only buffer behind one second...)

[drewbar]

The Internet is not a real-time medium. SHOUTcast is designed for the Internet. The SHOUTcast server has a built in buffer that is not adjustable. Don't expect this to change.

If you want real-time SHOUTcast is the wrong tool.

[username]

Ok so what would be the right tool? I'm not addicted to Soutcast (yet) so I can use anything if I know what is good for this...

PS- After changing the buffering on both the encoder and the player down to zero (but it changes itself back to 1 always...), there is now a 1 second delay. This is pretty ok, except that I'd rather not have to instruct the remote computers to 'go to your Winamp program, or if you dont have one, download it, then go to the pref's etc. then NSV decoder, and set everything to 0...' etc.

The best thing would be if it could be streamed to an embedded player on the web page, such as the NSV ActiveX's that I've seen around. Or maybe Java.

[drewbar]

If you are intending to stream over the Internet nothing will be real time. Just learn to deal with the delay.

[username]

But even on my own computer when I'm streaming and listening with 'localhost:port', there is still a delay. WHat about on the LAN, why cant one have realtime streaming there? I'm a little confused... How do people do videoconfrencing, are you saying that they say 'hi', then wait five seconds for the other person to see and hear the 'hi', then wait another five seconds for the response? I dont believe that anyone would be doing video confrencing if that were the case...

[Jay]

SHOUTcast is not video conferencing, might I suggest NetMeeting or some actual video conferencing software instead of shoutcast.

[DjDemonD]

Okay get a grip here......

Shoutcast is designed for the internet and has a buffer. FULL STOP you cant change it.

Video conferencing via the internet is jerky and jumpy because it uses very little buffer. Hence its almost real time but not quite otherwise it would be really hard to use.

If you want to do video conferencing to your own computer dont bother using a computer at all get a camcorder and a long cable and do it directly or buy a CCTV type home security camera not a web camera.

Or get a dedicated high quality high bandwidth business connection or Satelite uplink or whatever that is not subject to the same problems as a cheap home broadband connection, ooo I nearly forgot - best get one of these for the person your conferencing with aswell.

BTW the satelite feed you see on TV is a mixture of a little buffering and the time it takes for the signal to go 44480 miles (to geostationery satelite and back). About 1 second in total. It seems longer on TV because when the interviewer asks a question its 1 second b4 the subject hears it and another 1 second before the reply arrives.

[B0b]

Originally posted by ken52787
That is the buffer. Shoutcast uses this to provide QoS (quality of service). There is nothing you can do about it.

Sure there is!
Adjust the buffer settings for the Nullsoft NSV Decoder plugin in Winamp. Just set it to almost zero.

[Jay]

Originally posted by username
... PS- After changing the buffering on both the encoder and the player down to zero (but it changes itself back to 1 always...), there is now a 1 second delay. This is pretty ok... yea that's been mentioned.

[Inedible Bulk]

http://office.microsoft.com/home/office.aspx?assetid=FX010909711033

(http://www.microsoft.com/livemeeting goes to the same place)

Use that instead. Pay for it. It is what you want.

[Jeeper One]

Hi everyone:Originally posted by drewbar
The Internet is not a real-time medium. SHOUTcast is designed for the Internet. The SHOUTcast server has a built in buffer that is not adjustable. Don't expect this to change.

If you want real-time SHOUTcast is the wrong tool. As is ALL other forms of streaming media. Long and short of it is simple. If you want realtime - DO NOT USE STREAMING MEDIA.

Hope this helps :)

Cheers for now :)

[username]

You see, something really does not compute here. There are major companies that are a true competition to regular phone service, and they serve Voice Over IP. They must have very good quality service for people to be able to truly replace their landline phone and use their VoIP instead. Now if there is a way to have voice streamed (and both ways) in true realtime, then I simply cannot understand why video cannot be done the same way. Of course it will take larger bandwidth, but why couldnt it be setup on the same principles?

In truth, all I am looking for is a one way feed to be shown on a website that is just about really 'realtime', but what I'm thinking should apply to a full two way video conference, and all the more so to a simple one way feed.

What do you say? (Truth is that this is probably not for the Shoutcast Forum anymore, being that it seems from some of the posts that NSV is not the way to go... But since it was started, might as well finish it...)

[Inedible Bulk]

Hey, how about sometime you get two voip phones next to each other. Have one call the other. Put them both up to your ears. You'll realize how not-realtime they are.

There is no such thing as real time unless you're actually there.

[Jeeper One]

Hi everyone:

I have to agree with Bulk on this one dude.

ANYTHING involving video (or audio for that matter) and (especially) the Internet WILL NOT be realtime. There will ALWAYS be a delay of some sort.

I don't know how much plainer it can be put!

Does THIS make it clear now?

I don't want to sound like Bulk frequently does when HE gets on HIS soapbox, but apparently you seem to have a problem grasping what we are trying to tell you. Hopefully we've gotten through to you now.

Cheers for now everyone :)

[Jeeper One]

Originally posted by Jeeper One
Hi everyone:

I have to agree with Bulk on this one dude.

ANYTHING involving video (or audio for that matter) and (especially) the Internet WILL NOT be realtime. There will ALWAYS be a delay of some sort.

I don't know how much plainer it can be put!

Does THIS make it clear now?

I don't want to sound like Bulk frequently does when HE gets on HIS soapbox, but seriously dude....You apparently you seem to have a problem grasping what we are trying to tell you. Hopefully we've gotten through to you now.

Cheers for now everyone :)

[Jeeper One]

Oops...

I hit QUOTE instead of EDIT. Sorry Mods....

Cheers for now :)

[username]

Ok, 'realtime' is the wrong word. What I mean is 'almost realtime', being that if it werent almost realtime, no one would be going for Vonage and all those other companies... (However, with the streaming video, I have not been able to get it 'almost realtime', even if watching it on the same exact computer that its streaming from...)

[ken52787]

Originally posted by username
Ok, 'realtime' is the wrong word. What I mean is 'almost realtime', being that if it werent almost realtime, no one would be going for Vonage and all those other companies... (However, with the streaming video, I have not been able to get it 'almost realtime', even if watching it on the same exact computer that its streaming from...)

You're missing the point here. Shoutcast was not to be made 'almost realtime', unless your definition of that is 30 seconds. Even if watching from the same pc doing the streaming, there'll still be the delay because shoutcast isn't trying to stream realtime, even if bandwidth would allow it.

I don't know what you could use that'd help you, but I can say that shoutcast is not it.

[Jay]

your question has been over answered.

[username]

Ok thanks y'all. I sort of understand that A- It is pretty difficult to get 'almost realtime', let alone realtime, when streaming online. B- Shoutcast is not even designed to come close to that. C- There's not too much left to say here...

Bye bye (I might start a thread on a webcam forum... probably more relevant...)