Video delay

[nethawk]

Anyone know a way to speed up the video coming in through composite in? I am using a external tuner and am experiencing about a 2.5 second or so delay between the video and the audio. Anyone had a similar problem?

[stanger89]

You need to run the audio through the card also, the delay is from running through the MPEG encoder.

[nethawk]

See, my problem is I need to be able to control the channel changing through hardware, not software since I want regular users to be able to change the channel through a external controller, since the audio is going through there already. It's simpler for us to switch the audio through the external controller then the computer programs. I think they sell devices that slow down audio but I'm not positive on it. I can't figure out why it's slower to begin with honestly.

[Opus4]

The video is slower, right? It is being recorded to a file before that same file is being read for playback -- it is not truly 'live'.

- Andy

[nethawk]

Blast and per the FAQ there is no way to turn that off is there? Do you think the delay will be consistent at least?

[Opus4]

Originally posted by nethawk
Do you think the delay will be consistent at least?

Perhaps sometimes it will be consistent & sometimes it won't?

The audio isn't even going through the encoder card at all? If you ever pause the video, it sounds like the audio would just keep on going... talk about the actors continuing to speak after their mouths stop moving...

- Andy

[stanger89]

How do you plan on recording audio if you don't run it through the card?

[Opus4]

Originally posted by stanger89
How do you plan on recording audio if you don't run it through the card?

Another very good point!

nethawk: what is your actual goal here? Why are there so many videos playing on 1 computer? Maybe what you are trying to do needs a different type of solution...

- Andy

[stanger89]

Yeah, I saw your other thread and I'm thoroughly confused about exactly what you're trying to do.

[nethawk]

Basically, I have no intention to ever record anything. Ever. This is the only software that will let me watch more then 1 tv channel at once using different capture cards. I can't/will not use 90% of the features. I just need the thing to play the multiple channels at once. Why? It's inside of a emergency operations center and we need to be able to monitor different local tv channels at once, for example. I'd actually love to be able to do closed captioning but I have the blackbird cards so I'm out of luck right now.

[nethawk]

For all you following at home, my delay seems to start at about 2 seconds and increase by about 30 seconds a hour. I was 9 minutes behind this morning after leaving it running all night.

[Opus4]

I am missing the purpose of the computer in this, then. If you have no need to record anything, why use a PC at all? Why not simply split the cable and have it go to several TVs? They could all be on any channel you want. With different brands, their remotes should all work. Small TVs are fairly cheap. The computer doesn't seem to add any value for this if you aren't recording anything & since you aren't even recording the sound, you couldn't rewind to see some event again.

- Andy

[nethawk]

3 words for you: Dynamic Screen Sizing.

I can change the size of the windows across my 2 80" screens to whatever I want/need.

[Opus4]

Originally posted by nethawk
my 2 80" screens

You know... I _almost_ added an "unless you are using 2 very large monitors of some sort, in which case multiple large TVs probably just won't work!"

I guess I should have stuck with that thought...

I really don't know what you could do about the audio for several videos at once, especially since they are all going to go out the same output if you were to connect the audio-in the tuner inputs. And, I don't know what you would do about the delay by not having the audio go through the tuners.

You always want the same channels recording/playing? Maybe you could run one instance of SageTVRecorder for each tuner/channel & have it always record that one channel. But, then you still need a way to play those multiple videos, since it sounds like you want them all visible at the same time, but with mute control over individual videos. I'm just guessing now. Hopefully someone else will have a better suggestion...

- Andy

[Mr_X]

What about one of these? http://www.extron.com/product/product.asp?id=mvp104gx&subtype=35&view=feat

[nethawk]

You hit the nail on the head on what is my worse case scenraio type of situation. Having to mute and un-mute each individual window is cumbersome and since it is I want to avoid that if at all possible. Regarding Mr X's suggestion the easiest way to do this is through a individual hardware solution but you lose the ability to be able to dynamically size screens. At best, let's say you have a 4 way video splitter, the way they work, is they actually merge the 4 feeds into a single feed and then let you display that. You can switch through them as a main(full size) screen instead of the composite (4 feeds at once) but you can't, dynamically have computer/video data across the screen. Think of CC security camera's as using a hardware type switch. I wanted to go that route initially for it's simplicity.

[nielm]

Sounds like <obiwan>Sage is not the application you are looking for</obiwan>

if I understand you correctly, you simply want to display a number of live tv channels on a screen... you don't want to save them to disk, nor to have audio...

The PVR-250's then are overkill - they contain mpeg2 encoders which you do not need, and which adds cost... A very simple capture card such as a WinTV Express or ATI TV Wonder VE might me more suitable.
Sage is also overkill -- you don't need EPG, channel changing, pausing, replaying and saving (nor a picture or music module!) -- while at the same time not allowing you to do what you need (view live, not delayed video from multiple sources)

Then a quick-and-dirty solution would be 3 instances of graphedit, each rendering the preview pin (live not delayed video) of one capture card, using either the WinXP Video Renderer (VMR7) or the Video Mixing Render9 (VMR9) to get 3 resizable video windows... Audio would be handled separately.

A more complex solution would be to code this up into a small program (apparantly this type of DirectShow programming is trivial!)... I am sure there would be plenty of people who would code a small app like this for a modest fee (try doom9 forums, or shspvr forums)

Graphedit is freely available (from doom9 doom9 or in the MS DirectX SDK). SHSPVR forums have more info on using graphedit with a PVR-250...

[nethawk]

Will look into it tommorrow morning. It may work. I know the built in ATI software takes a total dump when you have more then one card inside. It wont play any video at all.

[nethawk]

Having trouble figuring out how to get GraphEdit to display the 'preview pin' from the cards. How do you do all that?

[nielm]

(cannot verify this at the moment, but
insert the DirectShow filter: Hauppauge winTV PVR capture.
this will add a box with connectors on each side
One of these connectors will be Video Preview (or similar)
Right click it and select 'render pin'

Also see http://www.shspvr.com/graph.html
Cool. he even has a how-to for realtime video preview: http://www.shspvr.com/graph_build/realtime_perview.html

(note -- most of the time there is no need to manually connect the ouput filters, just right-clicking the pin and select 'render' will automatically build a graph)