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SCS
01-14-2004, 02:55 PM
I'm using a Firestore to capture DV files from a camera using the AVI type 2 codec. My question is: If I play back a 720x480 DV clip in the VT [3]'s 720x486 dimensions, will my clip be resized, repositioned or left alone?

Jim_C
01-14-2004, 03:09 PM
The answer is .... C...
Left alone


jim

SBowie
01-15-2004, 04:31 AM
I haven't got time to double-check this this AM, but I think I'd like to humbly offer a different answer. DV is Even fielded. If it were left alone, it would have a fielding issue when played back. My guess would be that it is being dropped 3 scanlines, centering it vertically. (I could be wrong, as I said - but something must be happening to compensate for the field order issue, and I can only think of one other alternative.)

Jim_C
01-15-2004, 07:19 AM
Yea, never thought about that, puttin 720 x 480 into 720 x 486 gonna have to do something with it to center in frame. My feeble mind was only contemplating a resize up to 486.

Thanks for the enlightenment and correction Steve.

Does that count as my 'learned one thing for today'?
If so I'm going back to bed.


Jim

bradl
01-15-2004, 07:36 AM
Since VT3 resizes and centers everything to fit within the 720 X 486 canvas by default, it drops down three scanlines to center it.

You know, I really am adding nothing new to the discussion so I will stop now...

SCS
01-15-2004, 06:03 PM
I appreciate everybody's input, however I'm still confused.
Take a look at this DV clip I've attached in something like QT or Window's Media Player & you'll see it's a white box with an 'X' in it.

Now import this clip into a timeline or storyboard in VT [3].
Set the VT Vision to underscan and -- the darn thing is positioned with the top cropped off! If you try to move the clip vertically, then the bottom disappears at every position except it's original.

Could I have my VT's preferences set incorrectly?

Jim_C
01-15-2004, 07:03 PM
Not an answer and maybe even more confusion.
But if you import your avi into aura and export as a tga still it all will fit on underscan. Not as an avi tho.

Over my head.

Where did you create the X at?

bradl
01-15-2004, 08:48 PM
Your clip is 640 X 480. That is the problem. VT will play it fine but you should go in Control Tree (if you are using VT3) and adjust the size and aspect to fill the screen and look proper to the eye. Naturally, the quality will be reduced because your clip is smaller than standard NTSC video and will need to be scaled up to fill the screen.

I would suggest a new camera, new capture card, or check you codec settings.

SCS
01-15-2004, 09:01 PM
to Jim_C - What happened to the VT can handle any AVI format ;) ? To answer your question, I made it as a 720x480 graphic in Photoshop then imported that graphic into Premiere using the default DV settings and exported it as a DV AVI.

to bradl - the clip is definitely 720x480 I used the preset in Premiere to render it & I played it back in a DV camera to make sure.

Jim_C
01-15-2004, 09:03 PM
Hey Brad,

I see what you mean by wmp playing it at 640x480, but when I load it into Mirage, Aura or on the timeline all of them show 720x480.
This is loading into Mirage and Aura as new project so it's not inheriting any settings.

Also when on the timeline the size shows 720x480 and 100%.
When I drop an actual 640x480 onto the timeline I created it does resize it to fit the screen but shows it at 101.25%.


So I guess I'm thinking it is 720x480. But as we all know I have been wrong before.

Concerning the wmp thing, I've noticed a few times avi's I have made that I obviously know are at 720x480, they show 640x480.

so ... dunno,
try bringing the clip into Aura as new project. If it was 640x480 it should load it that size. But it loads 720x480.

so double dunno.

jim

bradl
01-15-2004, 09:10 PM
Jim,

I triple dunno your double dunno.

I am at home without VT or Aura/Mirage so I was just reporting what WMP said it was. Sounds like WMP is not to be trusted with it Properties info. Maybe a flag in the file triggers the 640 behavior for it.

:confused: :confused: :confused:

Ivan
01-15-2004, 09:11 PM
If you made this in Photoshop part of your problem may be the pixel aspect. Photoshop uses square pixels. If you set the aspect ratio to .9 this may solve the problem.

Ivan

Jim_C
01-15-2004, 09:11 PM
Originally posted by SCS
to Jim_C - What happened to the VT can handle any AVI format ;) ?

Any is a large 3 letter word.

And 'handle' is relative.



Did I say that anyway?

:rolleyes:


jim

ps.. never heard of this problem from anyone else.
Does not by any means it hasnt or doesnt happen,
but havent seen it pop up in any forums, & I spend way too much time in them.
Lets keep plucking and see what the chicken looks like underneath.

Ivan
01-15-2004, 09:24 PM
Ok, you win, nice trick. Now do you want to tell us how you did it? I did some testing and it appears as though VT is cropping the top and bottom 3 pixels. Nice catch. Have you emailed anyone at Newtek about this? I know Paul watches the board but it never hurts to send this to someone directly. They will either have a really good answer for you or they will fix it.

Ivan

Jim_C
01-15-2004, 09:32 PM
across a t newtek d o t c o m


would be THE man to report it to.
thats one great thing hopefully you'll find out, SCS, is that imo Newtek has the best tech support with very very close ties to its users thru this group, the 2 below, and others.


http://groups.yahoo.com/group/VTNT/messages

http://www.videotoasternt.com/forums/

welcome aboard (if you just joined, and welcome back if not)

bradl
01-15-2004, 09:36 PM
Originally posted by Ivan
I did some testing and it appears as though VT is cropping the top and bottom 3 pixels. I tried this earlier today just to confirm what I thought (and Steve said) that it would center the 480 in the 486 Y space so you would have 3 missing top and 3 missing at bottom. Normal VT behavior...

But the behavior described below:
Now import this clip into a timeline or storyboard in VT [3].
Set the VT Vision to underscan and -- the darn thing is positioned with the top cropped off! If you try to move the clip vertically, then the bottom disappears at every position except it's original. doesn't make any sense. I agree to fool with the SRC or DST aspect settings to fill the screen as needed. And if your are creating in PS, LW, Aura, DFX, AE, etc. and plan on using in VT, create it at 720X486, .9 Pixel Aspect and 29.97 FPS!

Jim_C
01-15-2004, 09:41 PM
Originally posted by Ivan
If you set the aspect ratio to .9 this may solve the problem.


aha!!! (i think)

When I loaded into Aura it showed aspect ratio at 1.

Could that have something to do with it?

jim

SCS
01-16-2004, 07:59 AM
to Ivan - also tried shooting test pattern cards with a camera - same results...

to Jiim_C - thanks... I'll send an email to him asap...

SCS
01-16-2004, 08:21 AM
One more thing...

Sorry to be so "questiony" but the docs that came with VT [3] are a little light on information - anyone written <Dan Ablan - type> books on the VT?


Thanks again everybody :)