Time Delay Needed for QC -$$$ if you can make it work--

Peterb · Joined: 13 Sep 2006 Posts: 2

Hi I'm looking for a way to precisely delay a live video feed at high rez in Quartz Composer.

I work with a dance company that has been using Isadora in live performance settings. We've run up against a nasty challenge.

Isadora lets us capture hi quality video (DV 720X480) apply a time/frame delay (say delay 230 frames) and then project it back at High/Full rez. The effect is that live dancers can interact with high rez projections of them selves from several seconds ago. Which is very cool-- however Isadora does a bit of a sloppy job -- the video sputters - speeds up/ slows down.

We love Isadora, But after talking with mark at troika tronics (maker of Isadora) we realized it may be quite some time - if ever -before Isadora can deliver this effect to our satisfaction.

We've been told that a better solution could be designed in Quarts Composer but I have yet to see anyone claim they can create such a time delay. Something that could be regular enough to sync to a beat and not slip with processor ups and downs.

I've been watching posts on many sites for months hoping someone would solve this but it hasn't happened yet. At this point we'd pay someone to create such a patch if indeed it can be done.

In a post at the Quartzcomposer-dev mailing list Pierre-Olivier Latour, Quartz Composer Architect, gave some indication it might be possible by using java coding outside QC.

We need a solution that can delay a live video feed by a variety of precise timings (ex: 8.2 seconds, 38.6 seconds -- Etc...) and still run in full res video at 24fps or better.

Please post any thoughts or leads as to where we might go to achieve this effect. And if you think you can create it please contact me.
Thanks.

-Peter

monkey · Joined: 16 Sep 2006 Posts: 7

Try this out, it's just a thought of mine right now:

With the Patch "Image With Movie" you can import a Movie, now right-click on it and set Timebase to external, now you can set the time where the movie shall play. Maybe it's possible to record directly to file or into QC, take that file and feed it into the "Image With Movie" patch and attach a Math or something to the Patch time then.

Sorry ...

QC start > Start Recording (File or Patch)
QC start > feed movie from above into Image with Movie patch with altered patch time.

I unfortunately have no cam, but i try to organize one and try it out.
yours

adi

monkey · Joined: 16 Sep 2006 Posts: 7

Download this qtz:
http://www.conficere.ch/qc/movie_delay.qtz

It shows what i mean with movie import and delay. Try it out, if you need help contact me (through mail if it's urgent). As i said, i have no working live input.

yours
adi

monkey · Joined: 16 Sep 2006 Posts: 7

AND ... if nothing else works, you should post your problem to the vvvv forum at http://vvvv.org/tiki-forums.php.
vvvv ist like QC but better Smile

It is designed for projects as yours and it's community and support is much better. It's free to look and play with, but if you are gonna make money with it you have to pay a fee.

monkey · Joined: 16 Sep 2006 Posts: 7

You should just try if it works if you connect the Video Output to the Movie Path. It let's me connect, but if it works ...

monkey · Joined: 16 Sep 2006 Posts: 7

Ok after some further investigation i have to tell you, that i think, in my humble opinion. There is no other posibility in QC to realise your project.

The javascript patch can't compute images, Sprites are not readable anymore. Dead ends where ever i tried Smile

go and get vvvv you won't regret it.

Peterb · Joined: 13 Sep 2006 Posts: 2

I'll try it out and see what happens- I'll let you know.

Thanks for the help

-Peter

Magdatt

Greetings Peter

I managed to create a time delay using some of Apple's Sample Code.

http://developer.apple.com/samplecode/QuartzComposerMatrix/index.html

With a little hacking I used the Frames Cache in Combination with QuartzComposer to create a precise delay of up to 500 frames (20 seconds) on low resolution movies. With DV quality only upto 5 seconds. With a better video card (got a Ati Radeon 9700 64 mb) I think it's possible to create a delay also near 500 frames.

I'm not advanced in using Xcode tools But I think it is possible to use video-in instead of a quicktime clip.

If you're still interested I could send you my hacked version of the Matrix and look into it a little further.
_________________
www.magdatt.nl