Chroma questions

abynum1 · Post by **abynum1** » Mon Apr 10, 2006 2:55 am

Hi guys. I just found this site and am I glad I did!
I'm about to buy either ulead video studio 9 (or 10 when it comes out.) I'm very interested in the chroma key features. My question is where do I get the background footage at and what am I looking for? I see lots of programs on e-bay that have short video clips that loop such as woods,water scenes,stars or whatever. I also see a lot of cds that you can buy that are just stills. Can you shoot video against a green screen and add a still pitcure as the backdrop? or does it have to be video only? What format or file type do the videos or stills have to be in in order to work w/Ulead? Is their a particular size or anything else I need to look for? Also, can you take digital stills with your digital still camera and add them as back drops for your video footage? Thanks!

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heinz-oz · Post by **heinz-oz** » Mon Apr 10, 2006 3:46 am

The answers, in a nutshell are, yes, yes, yes and yes etc. it all depends

abynum1 · Post by **abynum1** » Tue Apr 11, 2006 12:47 am

As am I very interested in buying this product, is there anyone that can be a little more specific in answering my questions? I was wondering what file types or format do the imported video/stills have to be in, and does ulead limit you to a certain size? Basically I just want to know what I need to be looking for when purchasing video or stills to use as a backdrop with the chroma key feature of Ulead and where is a good place to get them. Thanks for any help.

sjj1805 · Post by **sjj1805** » Tue Apr 11, 2006 1:07 am

The current version of Video studio is 9 but as you have mentioned version 10 will be released very soon.

Version 9 has two video tracks, one being named an overlay track.
Version 10 will have 6 video tracks.

What you do is this....
You place your backdrop on the main video track, this can be a still image which can be one of many formats such as bmp, jpg and many other still image formats. It is best to resize those still images so that they are a standard video size such as 720 x 576 (PAL) or 720 x 480 (NTSC)
Alternatively you can use a video on the video track which ideally would be DV Video or MPEG2 though it will accept a number of other video formats.

You now place the video that you wish to apply a chroma key to on the overlay track. This is a video where someone or something has been filmed with a solid background colour such as a blue or green background.
This is how they do the weather broadcasts on television.

You then use the chroma key function to make that solid background colour transparant so that the video/still image background now shows through.

This is how you can instantly "transport yourself" to different parts of the world.

Post by **Ron P.** » Tue Apr 11, 2006 1:12 am

Hi,

What file format depends on if you are going need the transparency (alpha) layer or not. If you are going to use them to overlay onto a video or another image, then the image formats would have to support transparency, ie; GIF, PNG, or TGA. The video format should be, since you are going to be editing , DV-AVI.

There have been recent discussion in this forum regarding size limitations for images in VS. This is something that just recently was brought to light. VS may have problems with extremely large image file sizes.

What I think you need to be looking for is tutorials, books, documents on Chroma-keying. Do you have experience with chroma-keying? I suspect that this is new to you, by the questions asked. Chroma-keying is not simply about overlaying images or videos that have been shot in front of a green or blue screen. One of the most important aspects is lighting.

Do a google search for chroma-keying and you should find a lot of information on it.

Where can you find video and images? Anywhere, if you fully understand the technique then about any image or video can be used.

Ron P.

abynum1 · Post by **abynum1** » Tue Apr 11, 2006 1:20 am

Thanks guys. That was the info I was looking for. I have been reading a lot on the lighting issues causinf the "spill" effect. I just wasnt too clear on Uleads requirements for importing video and stills. Thanks again!