720p from 1080p

PerroneFord

PerroneFord

Deals in Lead
Ok, this should be easy, but had some issues with it that I am hoping someone can help me with.

I shot something recently at 1920x1080p. I'd like to extract a 1280x720 image from it. I do NOT need the full frame. Essentially, I'd like to use the Pan and Crop and keyframing to move a 720 window over the 1080 footage via keyframes.

The issues I am running into are these:

1. Do I create the project as a 1080p or 720p project?
2. In the Pan/Crop do I do a "stretch to frame"?
3. When doing the render I select 720p for a size, but do I check the "stretch" in the render options?

Any help is appreciated.
 
If want you want is a 1280x720 crop from a 1080 image, then you're probably better off opening a 1080 project, setting the preview quality to Best (Full), saving a screen shot as a PNG image, and then doing the crop in Photoshop or Paint Shop Pro or MS Paint.
 
Sorry David,

I meant video images, not stills. Essentially, what I am doing is a de-facto mask. I am recording in 1080, but pulling 720 out of the center portion of the frame. This gives me some opportunity to reframe a bit in post, fix certain issues in the framing, etc. without having to zoom my image and create other issues.

I wouldn't do this for scripted work, but it's perfect for the web based stuff with moving subjects that are just going where they want...
 
My experience is that you can create a 720P project and reframe it with crop and keyframes.

Vegas is smart and downrez first when you start to render. So any crop will use the best possible quality.
 
Well I did the pan/crop within a native footage timeline and it worked quite well. I'll try it the other way today and see what we get.
 
I agree; work in a 720 project and create a 1280x720 crop box. However, set the project video quality setting to Best.
 
Ok, twist.

This project was shot in HDV. So I have 1440x1080 non square. I want to get to 720p square. I've set the timeline to 720p square, my finishing format.

The problem now becomes what to change my Pan/Crop settings to. It looks like I set it to 1280x720 and leave the rest of the defaults. Yes?
 
Ok, I think I found the magic bullet I was looking for. Every time I rendered the video it was letterboxing. What I had to do was to set the project for 1280x720, but change the pixel ration to 1.33 (HDV pixel shape) instead of square pixels which is what the finished format would be.

When rendering, I had to set the pixel shape to match the project to keep it from letterboxing.

So it appears that when doing these kinds of conversions, it's imperative that you set the project and render settings for pixel shape to match the SOURCE and not the final format. Otherwise it doesn't work right.

Alternately, I could have rendered the source to a square pixel 1080p file and removed some of the gyrations.
 
If you import a 1440*1080 footage with pixel aspect ratio of 1,333

Both your project (720P) and your final render should have square pixels (1,0)


Because vegas reads the orginal footage as 16:9 and the project as 16:9 and transforms the 1080P footage to 720P with the aspect ratio intact.

If your project is 1280*720 and you set the pixel aspect ratio to 1,333, it will become cinemascope ratio with black bars left and right of the 16:9 footage.

Have you checked that the orginal footage has pixelaspect ratio 1,333 when you imported it into vegas?
 
Yes, I checked the media. It was not imported. I was merely an m2t file that I dropped onto the timeline. It was recorded at 1440x1080.

My current project properties are 1280x.720 with pixel ration 1.33. I did a render from the timeline to Mainconcept mp4 at 1280x720 with a 1.33 ratio, and everything came out as it should have. No black bars anywhere.
 
Maybe so. But it seems to be working just fine.

So let's review just in case someone wants to tackle this.

Source is 1440x1080 HDV with PA of 1.33:1
Project is set at 1280x720 with PA of 1.33:1
Pan/Crop is set to 1280x720
Render is set to 1280x720 with PA of 1.33:1

Footage renders at 1280x720 cleanly with no bars on top/bottom or sides.
 
Solved it

When you crop the footage as 1280*720 it treats the 1440*1080 footage as 4:3 and your crop becomes a 2,37:1 crop.

When I crop devided with 1,333 (960*720) it cropped as 16:9

This could be a bug.


edit

found out that the cropping just uses the the orginal framesize to specify were the crop will be. 960*720 will be equalient to 1280*720 in reality.
 
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You're right. It's screwed up. I created a new project, HDV 1080, and dropped the footage onto it. I'm now burning 1920x1080 square pixels from that. When that's done, I'll proceed to do what I was doing before.

Thanks for everyone's thoughts.
 
You should not have the project set with a PAR of 1.333 if the dimensions are 1280x720. That's a PAR 1.000 frame dimension.

If you have 1440x1080 HDV in a 1280x720 project, at default settings in pan/crop, set the width to 960 and the height to 720. Then render as 1280x720 with a PAR of 1.000. It should come out right.

(If, in pan/crop, you have the "Maintain Aspect Ratio" button pressed, if you typed in 720 for the height, the width would automatically become 960.)
 
Dang David... about a hour too late! :)

But since I'll be doing this with another project shortly, it'll save me a step. I appreciate that. Now if I could only make the EX1 give a guide frame of 67%, my troubles would be over...

-P
 
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