DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   What Happens in Vegas... (https://www.dvinfo.net/forum/what-happens-vegas/)
-   -   Transitions operating on pre-cropped image (https://www.dvinfo.net/forum/what-happens-vegas/196088-transitions-operating-pre-cropped-image.html)

Ian Stark April 14th, 2009 06:54 AM

Transitions operating on pre-cropped image
 
Not sure if that title makes sense!

To explain by way of example, if I take a clip or still image and crop it using pan/crop, then apply a transition, for example Flash, to the leading edge of the clip, the flash shows as though it was affecting the area of the pre-cropped clip/still, rather than the resized version. It looks ugly.

This seems to be the case with all transitions. In other words the transition is processed before the crop. Off the top of my head I can't think of any good reason for it to be done this way around (although I am sure others will put me right!).

I'm guessing that this is similar to the issue of certain transitions in widescreen projects where the suggested workaround is to mask off the areas where the transition is not wanted.

That workaround might be OK for things like the Flash transition, but wouldn't work so well on things like Page Peel or Blinds or other transitions with that kind of motion. Personally I don't often use the snazzy transitions but recently I have used the NewBlueFX Roll transition, which is where I first came across this issue.

Are we stuck with this or am I missing something?

Cheers,

Ian . . .

Edward Troxel April 14th, 2009 07:10 AM

If you're saying you're creating a mask of some sort and the transition applies to the black bars as well as the image, you are correct. You would typically place a mask on the track above all other tracks to block anything from appearing in the black area.

Ian Stark April 14th, 2009 07:24 AM

Hello Edward,

I'm specifically talking about applying a transition to a clip that has been cropped using the pan/crop tool. No masks involved.

I only mentioned masking as being the recommended workaround for the problem, but, like you say, that will just block anything from appearing in the masked area - it won't resize the transition. Fine for things like Flash, but not fine for other transitions. For instance, a page peel would be half completed before it appeared in the unmasked area, which would look wrong.

Does that make sense? Perhaps easier to show rather than put in words!

What I was wondering is if there is any way to get the transition to be processed AFTER the pan/crop so it only operates on the resized image. The current order of processing seems wrong.

Edward Troxel April 14th, 2009 07:43 AM

Might be simpler if you post a VEG file.

But as you said, basically transitions apply to the VIDEO FRAME - the entire video frame.

Ian Stark April 14th, 2009 07:52 AM

Yes, just waiting for another project to render then I will put something together. Thanks, Edward.

Ian Stark April 14th, 2009 08:34 AM

3 Attachment(s)
OK, in creating a sample to explain the situation I realise that the circumstance under which this problem occurs is when I change the aspect ratio in the pan/crop tool.

Attached are three stills, one that shows a page peel in progress and one that shows a flash transition at about the midway point. The third shows how I have cropped the original clip.

It's clear that the transition doesn't see that I have ignored the aspect ratio and cropped a widescreen image to look square. The transitions operate on the area that would have been occupied by the clip if I had maintained the original aspect ratio.

Hope that makes more sense of what I was trying to explain earlier.

You can see that the idea of using a mask above the clip would work fine for the flash transition but would not work so well on the page peel (or similar). Not that I am a fan of page peels, just using that example to illustrate the point!

I still think it's wrong!


All times are GMT -6. The time now is 11:51 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network