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View Full Version : RTV Capture and Format Size



Jim_C
10-22-2004, 08:30 AM
OK I just noticed after capturing over an hour of RTV pieces, that the format size in the capture panel is 720x480. RTV is 720x486 correct?

And if correct should the capture panel have automatically switched the format size to reflect that, and if correct do I need to recapture all this. :eek:

It looks just fine on the timeline when played back.

If you can capture RTV at 720x480, why have we all been capturing at 720x486 then worrying about clipping lines in tmpgenc and such?

What up wit dat?
:confused:

Thanks...
Jim

ted
10-22-2004, 10:38 AM
You will have a problem if the video is viewed on a projection system.
You should be using 720 X 486.
I'm not sure, but when you bring the video back into VT, it "might" automatically stretch the video???

Jim_C
10-22-2004, 11:08 AM
Thanks Ted,

No go to VT Edit stretching to 486 and when I do it manually it's unuseable.
You would think the capture panel would make the change when you select RTV, just as the audio changes for various codecs.

Interesting.. I just did a test....

I set picvideo as the video codec and changed the format to 360x240.
Now when I switch the Video codec to RTV it changes the format to
720x480!! not 720x486......

Newtek?? Is this a bug? If not it at least sounds wrong, it should switch the format to 720x486.

ScorpioProd
10-22-2004, 12:28 PM
Guys, this is no bug.

720X480 and 720X486 are both perfectly valid sizes for RTV.

Personally, I have no use whatsoever for 486 lines, and life would be much better if 480 lines was all we had.

DV/DVCAM/DVCPRO is 720X480, period.
DVD MPEG-2 is 720X480, period.

720X486 is only for legacy "true" D1 stuff that hasn't gotten with the modern program. Unless you're broadcasting, and have equipment that actually needs it and uses it, there's no need for 720X486.

As for projection, there is nothing about projection systems that need 720X486. The resolution you digitize at is ARBITRARY when you are coming from an analog source to a digital capture. It's not like you're magically getting a bigger picture. And since you will probably be feeding the projector from a digital source, and the digital sources are typically 720X480 nowadays... Anybody hooking up a D1 deck to their projector?

And it certainly will do nothing to eliminate the overscan artifacts that projectors will show that will be there no matter what you do, especially with how the VT's transitions do funny things out there in overscan land.

720X486 is an albatross around the neck of the VT that none of the DV based systems worry about. Remember, even when you capture in 720X480, internally the VT only works in 720X486, so you can't escape it no matter what you do.

Oh, and no, it won't scale it, that would be bad if it did, it will just stick 3 black lines on top and 3 black lines on the bottom internally.

ted
10-22-2004, 02:37 PM
I'm doing hardware stuff so I can't verify this. but...
If you have a background at 720 X 486, and you zoomed a 720 X 480 captured video to full screen over the background, wouldn't you see the background behind the video?

ScorpioProd
10-22-2004, 03:43 PM
I don't think you would, you'd just see a little black edge on the top and bottom.

Again, all of this in the overscan area that the VT doesn't worry about anyway.

Jim_C
10-22-2004, 03:56 PM
Thanks Eugene!


Jim

Jim Capillo
10-22-2004, 04:11 PM
I'm doing hardware stuff so I can't verify this. but...
If you have a background at 720 X 486, and you zoomed a 720 X 480 captured video to full screen over the background, wouldn't you see the background behind the video?

If you encoded the file for playback on the web (windows media file, for example), you would see it..... but you could either crop the 1st clip or expand the overlay via the positioning panel.

ScorpioProd
10-22-2004, 08:44 PM
True, but again, the initial intent of the VT was always TV, so it has never delt with overscan areas for non-TV use. Even when I use perfectly clean edge-to-edge DV video, the DVEs of the VT simply don't cover the overscan area. There are reasons for this, but the thing is it is a pain for applications where you do see edge to edge. And these are more and more the "typical" applications a lot of us need.

I would recommend the cropping option over the scaling option.