Chroma key problem

[sebazvideo]

I have a few small clips that consist of me in front of a green screen. The green screen, however, doesn't take up the whole frame, and in some of the clips, the parts of the frame that are not me or the green screen are not very easy to remove with just the rectangle tool in the chroma key effect in Neo Booster. So to make it easier, I opened one clip in Vegas, made a mask to remove the unwanted parts and leave only me and the green screen behind me. I exported it as an uncompressed RGB with alpha channel, and when I loaded in Neo I made sure that the alpha channel was present by putting this clip on top of another, and indeed, the areas that I had eliminated by using the mask in Vegas were totally transparent and I could see the clip in the track below in those areas.

The problem is, when I loaded the chroma key effect to the clip to key out the green screen and leave only me, the green screen is keyed out, but now what was totally transparent became black. I tried all the different settings in the effect configuration, including the ones in the detail area, and there's nothing I can do to get rid of the black. It's as if this effect wouldn't recognize that there's an alpha channel, because I can even use the picker on the black area that is supposed to be transparent and it keys it out, but of course it leaves the green screen and keys out parts of me that are dark.

So, is this because the chroma keyer in Neo doesn't recognize alpha channels, or am I doing something wrong? I also tried converting the uncompressed RGB file to the Canopus Lossless codec and Canopus HQ Online codec with the same results.

[junk_man32]

Originally Posted by sebazvideo

I have a few small clips that consist of me in front of a green screen. The green screen, however, doesn't take up the whole frame, and in some of the clips, the parts of the frame that are not me or the green screen are not very easy to remove with just the rectangle tool in the chroma key effect in Neo Booster. So to make it easier, I opened one clip in Vegas, made a mask to remove the unwanted parts and leave only me and the green screen behind me. I exported it as an uncompressed RGB with alpha channel, and when I loaded in Neo I made sure that the alpha channel was present by putting this clip on top of another, and indeed, the areas that I had eliminated by using the mask in Vegas were totally transparent and I could see the clip in the track below in those areas.

The problem is, when I loaded the chroma key effect to the clip to key out the green screen and leave only me, the green screen is keyed out, but now what was totally transparent became black. I tried all the different settings in the effect configuration, including the ones in the detail area, and there's nothing I can do to get rid of the black. It's as if this effect wouldn't recognize that there's an alpha channel, because I can even use the picker on the black area that is supposed to be transparent and it keys it out, but of course it leaves the green screen and keys out parts of me that are dark.

So, is this because the chroma keyer in Neo doesn't recognize alpha channels, or am I doing something wrong? I also tried converting the uncompressed RGB file to the Canopus Lossless codec and Canopus HQ Online codec with the same results.

yeah...um same problem here. there is no full alpha support...its a real bummer. when im masking in boris and the background is supposed to be transparent...its black...but there is a solution. use the overlay composite of "Lighter" to overlay the tracks...it will be good. I dont know if neo has this but it should.

[Jerry]

Originally Posted by sebazvideo

I have a few small clips that consist of me in front of a green screen. The green screen, however, doesn't take up the whole frame, and in some of the clips, the parts of the frame that are not me or the green screen are not very easy to remove with just the rectangle tool in the chroma key effect in Neo Booster. So to make it easier, I opened one clip in Vegas, made a mask to remove the unwanted parts and leave only me and the green screen behind me. I exported it as an uncompressed RGB with alpha channel, and when I loaded in Neo I made sure that the alpha channel was present by putting this clip on top of another, and indeed, the areas that I had eliminated by using the mask in Vegas were totally transparent and I could see the clip in the track below in those areas.

The problem is, when I loaded the chroma key effect to the clip to key out the green screen and leave only me, the green screen is keyed out, but now what was totally transparent became black. I tried all the different settings in the effect configuration, including the ones in the detail area, and there's nothing I can do to get rid of the black. It's as if this effect wouldn't recognize that there's an alpha channel, because I can even use the picker on the black area that is supposed to be transparent and it keys it out, but of course it leaves the green screen and keys out parts of me that are dark.

So, is this because the chroma keyer in Neo doesn't recognize alpha channels, or am I doing something wrong? I also tried converting the uncompressed RGB file to the Canopus Lossless codec and Canopus HQ Online codec with the same results.

Not having used Neo, I will only tell you if you have a green screen, and it is properly lit with talent, and they are properly lit, you should be able to get a very clean green screen effect with one click(Per Edius). I guess Vegas would not export an HQ file with alpha. Yes, the codec does support alpha.
You are talking about 2 different things here:
1. Alpha punchout...with this if you have a subject with prepared alpha channel it will indeed work in Edius. There is no need to go uncompressed. It will do it with a prepared HQ with alpha. All you have to do is place it on the timeline.

2. Green Screen punchout...with this you have talent in front of a green screen and you just eliminate the green with the chromakey tool while the clip is overtop of what you want to show through.

If you are not getting this to work..you must be doing something wrong.
If you have created a clip with both green screen and alpha included, it is easier for the chromakey tool to work with a single color on 1 pass.

What I do is put the rectangle around the area that you want to eliminate(other than the green screen and talent) and use the color picker to match the existing green screen color and fill the box. Then it will ALL disappear in one shot.
Really simple.

[sebazvideo]

Originally Posted by junk_man32

yeah...um same problem here. there is no full alpha support...its a real bummer. when im masking in boris and the background is supposed to be transparent...its black...but there is a solution. use the overlay composite of "Lighter" to overlay the tracks...it will be good. I dont know if neo has this but it should.

Well, here's the weird thing: I looked up composite in the manual, and on page 410 there is a section called "Composition" that shows a screenshot of the effect tab, and under Keyers you can see an item called "Blend" which holds all the compositing modes, such as Lighter, Darker, Color Dodge, etc.

The problem is, in my installation of Neo 2.5 Booster it's just not there. Under Keyers I only have three items: Chroma Key, Luminance Key and Picture in Picture, and I always did. And this is on a fresh install of Windows 7 from less than a month ago, and my Neo Booster install CD was sent to me by Panasonic because it was a bundle with a camcorder I bought from them, but as far as I've read on their website it's supposed to be the same version that everybody has, it's not a demo or anything similar.

I'll keep looking into this to see if I'm doing something wrong.

[Jerry]

Did you try my method ?
Can you post your clip somewhere so I can
download it?

[sebazvideo]

Originally Posted by Jerry

Did you try my method ?
Can you post your clip somewhere so I can
download it?

Thanks, Jerry. If you're talking about the rectangle in the chroma key effect, like I said in my first post, it's not viable because the area that I want to eliminate that is not green is not as uniform as to be eliminated using the rectangle tool, it needs a mask, but Neo Booster doesn't offer that, that's why I had to mask it out in Vegas and export as an uncompressed RGB with alpha channel. The problem is that the chroma key filter in Neo converts alpha to black for some reason.

I appreciate your help, but I'd rather not upload a clip because it's just me fooling around, it's not a professional project, but rather a learning project. It seems to me that the chroma keyer in Neo is better than the one in Vegas. It has a lot more parameters to fine tune, while Vegas has only three. It would be great if the chroma keyer in Neo had a mask that can be used in any shape you need, not just as a rectangle.

[johnsirb]

Originally Posted by sebazvideo

The problem is, when I loaded the chroma key effect to the clip to key out the green screen and leave only me, the green screen is keyed out, but now what was totally transparent became black. I tried all the different settings in the effect configuration, including the ones in the detail area, and there's nothing I can do to get rid of the black..

you do have the original green screen footage on the top layer, correct?
yes it's black if there's no images under the clip

[sebazvideo]

Originally Posted by johnsirb

you do have the original green screen footage on the top layer, correct?
yes it's black if there's no images under the clip

Yes, I do have the green screen footage on the top track, and there is a track with footage below. Before I apply the chroma key effect, I can see on top me and the green screen, but around the green screen I can see the underlying track footage because that's the part I eliminated using a mask in Vegas. Now, as soon as I apply the chroma key, I can key out the green and it shows through the footage in the lower track, but the area that was transparent is now black.

[Jerry]

Originally Posted by sebazvideo

Yes, I do have the green screen footage on the top track, and there is a track with footage below. Before I apply the chroma key effect, I can see on top me and the green screen, but around the green screen I can see the underlying track footage because that's the part I eliminated using a mask in Vegas. Now, as soon as I apply the chroma key, I can key out the green and it shows through the footage in the lower track, but the area that was transparent is now black.

If you have after effects I would use it. One thing you
probably learned with this experiment is to make sure
you have your green screen perfect before shooting.
Sure does save aot of wasted time. Key the
green screen out and export.


Place the new clip on the timeline.
Either use luma key or chroma key
on the new clip so that the lower video
will be seen through the black portions.
See what you get.

[junk_man32]

Well im not sure of antoher way for neo than if you dont have the "lighter" blend filter. i also use this blend for custom masks in boris.