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Old June 21st, 2008, 10:04 AM   #1
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Need a variable video delay

I have been searching for some time for a piece of equipment to insert a variable video delay into the signal from a video camera with composite output. I have found a product called DelayLine from a company called Ovation in the UK.

The units are great because they delay video in 16 increments on units with a maximum delay of from .8 sec up to 120 sec.

The problem is the price, about $800.00 US.

I need to delay 3 signals from the same camera using some sort of delay technology allowing delays in the 2-3 second range. Delay of the signal will be post distribution amplifier into 3 LCD screens. Unfortunately, That puts me at $2400.00 to achieve the desired effect.

If anyone reading this has any ideas about equipment or even a direction for research that I haven't considered, please respond.

thanks
--rick
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Old June 21st, 2008, 12:53 PM   #2
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a pc could do that.
just capture from firewire (small delay here from about .5 sec to 1 sec) while capturing on disk.
but you can capture from analog with almost no delay.
then you simply play with 3 differents players with selected delay.
should be easy to write that with visual basic in 5 minutes.
if you use a 3 display computer (the matrox triple head box would be great for that, about 300$ ) you can set 3 screen from the same notebook.
in VB (and other language) you simply set 3 players object and specify top corner, width and height to match you screen config.
for example if you use a matrox triple head with 3 screens set a 800x600 (enough for video),
each player will get width and height set as 800x600 and top corner (x,y) set as 0,0 - 799,0- 1599,0
then you set the source file name as the captured file (some format cannot be read while capturing like most AVI, but WMV and MPEG can)
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Old June 23rd, 2008, 05:42 AM   #3
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Player?

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Originally Posted by Giroud Francois View Post
then you simply play with 3 differents players with selected delay.
should be easy to write that with visual basic in 5 minutes.
Giroud,

Thanks for the information.

Actually, I need a player that will allow for full screen playback of each of the feeds. I looked at the matrox box and it seems to be a good start. Do you have a recommendation for a player that will capture, allow for a delay of 2 to 3 seconds, and produce a full screen playback at the same time on a Windows XP platform.?

That seems a rather daunting task to me.

--rick
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Old June 23rd, 2008, 06:38 AM   #4
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as i said, most players are giving a full screen option, but in the case of the matrox box, this is not very usefull, since full screen would means across all the three screens.
Some players (like the new windows mediaplayer) do not even allows several players to be opened at the same time (but the plain old media player 6.4 will and is a great stuff to have anyway)
that is why some use of some programming language would ease the process.
In your case the capture and the play are totally separated and you can lauch one processe to capture, set it into the background, and then lauch the multiplayer.
Personnaly i would mix all in one program because i am a lazy guy (like all good programmers usually are).
That is why a would creat a form in VB, resize it automatically to full screen, load three player object, and set position propertie as needed. this takes 5 minutes.
the remaining is easy. You could do the same with a web page and three players (quicktime?) object embedded. IExplorer can be run full screen there is no issue with windows menu or toolbar.
For capture, you will find dozen of VB add-on allowing that. The only touchy thing here, is you have to make sure that the file receiving the video capture can be opened by the players at the same time. most of utilities capturing directly to mpeg2 allow that. if it is too tricky, you can even use a pc to encode video (with the free windows media encoder) then read the stream with three web page (on same pc with VLC player for example or mediaplayer 6.4). so no programming is needed.

windows media encoder works really fine with the firewire input.
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Old June 23rd, 2008, 08:01 AM   #5
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If you are going to have multiple playbacks from the same file (as it's being captured and each playback with a different delay, no less), you will need to buffer the video in RAM somehow, to avoid an unwieldy number of disk seeks.
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Old June 23rd, 2008, 09:03 AM   #6
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If you can use DV then our Enosoft DV Processor will do the trick for you. It can take a live DV feed and split it into multiple copies, impose a user-defined delay on each and send the delayed DV streams to full screen PC displays.
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Old June 24th, 2008, 02:59 PM   #7
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I think this is it.

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Originally Posted by John Miller View Post
If you can use DV then our Enosoft DV Processor will do the trick for you. It can take a live DV feed and split it into multiple copies, impose a user-defined delay on each and send the delayed DV streams to full screen PC displays.
John,

This sounds as though it is precisely what I need. However, I am not the most technical person in the world, so allow me to clarify my proposed setup.

I want to have a single camera (i don't have the camera as yet, so I can purchase digital) mounted at the center top of one 19" LCD monitor. The video from the camera to that monitor is to be delayed by 2-3 seconds.

There will be two other 19" LCD monitors, one mounted to the left and one mounted to the right of the first monitor. The same camera feed will go to each of these monitors, one delayed by 1-2 seconds, the other by around 0.5-1 second.

All LCD monitors can be digital. I am currently looking at 19" Dell UltraSharp.

Will the Enosoft software accomplish this? And, if I use a laptop pc, what sort of inputs and outputs would it need in order ensure proper setup?

Thanks for your help,
--rick
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Old June 24th, 2008, 05:54 PM   #8
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Quote:
Originally Posted by Rick Alexander View Post
John,

This sounds as though it is precisely what I need. However, I am not the most technical person in the world, so allow me to clarify my proposed setup.

I want to have a single camera (i don't have the camera as yet, so I can purchase digital) mounted at the center top of one 19" LCD monitor. The video from the camera to that monitor is to be delayed by 2-3 seconds.

There will be two other 19" LCD monitors, one mounted to the left and one mounted to the right of the first monitor. The same camera feed will go to each of these monitors, one delayed by 1-2 seconds, the other by around 0.5-1 second.

All LCD monitors can be digital. I am currently looking at 19" Dell UltraSharp.

Will the Enosoft software accomplish this? And, if I use a laptop pc, what sort of inputs and outputs would it need in order ensure proper setup?

Thanks for your help,
--rick
All of this should be possible. There are different ways to achieve it and they differ according to hardware - the software will be the same.

Our software can send the incoming DV either to a PC display or to another DV device which, in turn, is connected to an NTSC video display.

To use three 19" PC monitors, you will need a graphics adapter (or multiple adapters) that can support three monitors such as the Matrox TripleHead2Go. We have tested our software with dual monitor cards but not with more than two displays - it shouldn't present a problem, though. The downsides with this option are:

* the laptop must be powerful enough to render three DV streams full screen
* the DV is 720 x 480 @ 29.97fps and it is interlaced - when displayed on a PC display, it won't look as good as on an NTSC display. The different frame rate and lack of interlaced support (with the Matrox unit) will give less than optimum results.

To maintain the video quality and reduce the processing power needed, you can use the DV output option from the software. That would require a total of four DV devices (your input camcorder and three camcorders/converters). In turn, this will need two separate FireWire interfaces - e.g., a laptop's built-in one + a PCMCIA card. DV converters start at ~$135 each making three of them not much more expensive than the Matrox triple head unit. Instead of three 19" PC displays, you would use three 19" NTSC displays which may be cheaper, too.

To get a feel of what the software can do, we can set something up that will show the three delayed images in separate windows on the PC's desktop. I can create the instructions for you to try out.

It would be easiest to take this off-line - you can PM me or email me direct at johnATenosoft.net

John
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Old June 25th, 2008, 01:12 AM   #9
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i just wrote a little apps in VB to test this (i got two DV files) playing easily on the same screen (1920x10200) . with the matrox box, the lowest resolution you can get is 2400x600 or the equivalent of three 800x600 screen that is enough to play video.
i need to insert into the code the capture feature. Since you do not tell if the video need to be recorded, it could be possible to just keep enough frames in memory to get the delay.
my old P4 3Ghz is able ro play 4 or 5 DV stream at once from files so i am pretty confident that any recent PC will do.
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Old June 25th, 2008, 05:36 AM   #10
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No recording necessary

Quote:
Originally Posted by Giroud Francois View Post
Since you do not tell if the video need to be recorded, it could be possible to just keep enough frames in memory to get the delay.
Giroud,

The video does not need to be recorded beyond what is necessary for delay.

Thanks so much for helping,
--rick
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Old June 25th, 2008, 05:45 AM   #11
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The NTSC Direction

Quote:
Originally Posted by John Miller View Post
To maintain the video quality and reduce the processing power needed, you can use the DV output option from the software. That would require a total of four DV devices (your input camcorder and three camcorders/converters). In turn, this will need two separate FireWire interfaces - e.g., a laptop's built-in one + a PCMCIA card. DV converters start at ~$135 each making three of them not much more expensive than the Matrox triple head unit. Instead of three 19" PC displays, you would use three 19" NTSC displays which may be cheaper, too.

To get a feel of what the software can do, we can set something up that will show the three delayed images in separate windows on the PC's desktop. I can create the instructions for you to try out.
John,

Going with NTSC certainly seems a viable option. And, I really appreciate your willingness to set up a prototype. I will contact you using the supplied email address.

thanks very much,
--rick
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