What is "image matte" and "video matte"
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matt_magnone
What is "image matte" and "video matte"
Hi. What I did was a made a sample video of me with a basket covered with green screen material. Check the link below. What I was wondering is, what is image matte and video matte? What are they useful for? I did some experimenting, but I can't keep the ball inside the green only. I had to move the ball manually using the picture in picture, which didnt come out too good. Can anyone think of a way to keep an object in the green, no matter where it moves...???? Or know of any software that does this...??? Thanks
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Terry Stetler
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Typically;
An image matte can be either a plain black, white and gray image used to mask out certain parts of an image. Either the black or white component can act as the mask, with its opposite number being transparent, but the gray is used to "feather" the edge between black and wite to give a smoother look. In this way you can limit the effect of a filter or overlay to a specific region. Image mattes can be created in any photo editor.
A video matte is the same thing, but consisting of a series of image mattes (frames) with each designed to work on a specific frame in a video sequence. The creation of a video matte is a more dicey matter and usually are best generated in programs like Video Paint (included in MSP7 but now part of VideoGraphics Lab), After Effects etc. Video mattes can also be created in PhotoImpact or Photoshop if you're proficient with them.
There is also matte art. Here a photo or video of a scene, often synthetic, with a portion that can be keyed out and that portion replaced by live action actors. Example: the scene in the Genesis Cave in ST-Wrath of Kahn. The cave itself was an animation (the matte art) with a keyable portion, while the opening into it from the control room with Kirk etc. was filmed footage.
An image matte can be either a plain black, white and gray image used to mask out certain parts of an image. Either the black or white component can act as the mask, with its opposite number being transparent, but the gray is used to "feather" the edge between black and wite to give a smoother look. In this way you can limit the effect of a filter or overlay to a specific region. Image mattes can be created in any photo editor.
A video matte is the same thing, but consisting of a series of image mattes (frames) with each designed to work on a specific frame in a video sequence. The creation of a video matte is a more dicey matter and usually are best generated in programs like Video Paint (included in MSP7 but now part of VideoGraphics Lab), After Effects etc. Video mattes can also be created in PhotoImpact or Photoshop if you're proficient with them.
There is also matte art. Here a photo or video of a scene, often synthetic, with a portion that can be keyed out and that portion replaced by live action actors. Example: the scene in the Genesis Cave in ST-Wrath of Kahn. The cave itself was an animation (the matte art) with a keyable portion, while the opening into it from the control room with Kirk etc. was filmed footage.
Terry Stetler
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sjj1805
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Terry,
Good explantion and saved me a bit of time, had recently been playing about with image mattes and now understand what the other two are.
Going back to the problem that matt_magnone has, I was interested by the video he has placed as an example. Any suggestions on how best to go about that little task he is working on, I can see a few ideas creeping to mind.
What he has insn't a simple overlay of a football, His hands are front of the ball whilst his body is behind it. Looks like some sort of layering teaser.
Steve J
Good explantion and saved me a bit of time, had recently been playing about with image mattes and now understand what the other two are.
Going back to the problem that matt_magnone has, I was interested by the video he has placed as an example. Any suggestions on how best to go about that little task he is working on, I can see a few ideas creeping to mind.
What he has insn't a simple overlay of a football, His hands are front of the ball whilst his body is behind it. Looks like some sort of layering teaser.
Steve J
Steve,
The best way to accomplish this would be as follows. Bear in mind I'm using MSP7. If one chooses to use a image(soccer-ball), I would use one containing alpha channel with background transparency like a tga, psd, png, gif, etc... In editor, overlay with alpha channel selected and move this image using moving path centered between the hands. Using COOL3D PS would be even better as one can use the video as a background and then using a 3D model(soccer-ball) rotate, position and even add shadow to give the proper perspective. Now save this as 24 bit AVI. Open up Video Paint module and use the original clip without ball. Paint solid color over the hands frame by frame. Tedious work making the layer mask but worth it. Save as .uvp file. Now in editor V1 track will be AVI w/ball clip. V2 will be original clip without ball. In V2 Overlay Options, select Mask and open saved .uvp file. For Type select Alpha Channel. That's it.
The best way to accomplish this would be as follows. Bear in mind I'm using MSP7. If one chooses to use a image(soccer-ball), I would use one containing alpha channel with background transparency like a tga, psd, png, gif, etc... In editor, overlay with alpha channel selected and move this image using moving path centered between the hands. Using COOL3D PS would be even better as one can use the video as a background and then using a 3D model(soccer-ball) rotate, position and even add shadow to give the proper perspective. Now save this as 24 bit AVI. Open up Video Paint module and use the original clip without ball. Paint solid color over the hands frame by frame. Tedious work making the layer mask but worth it. Save as .uvp file. Now in editor V1 track will be AVI w/ball clip. V2 will be original clip without ball. In V2 Overlay Options, select Mask and open saved .uvp file. For Type select Alpha Channel. That's it.
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matt_magnone
What I did was, I covered a basket with green material. If you key that out you can put something in place. The problem I am having is that I can't get rid of the excess black. Anything can be overlayed in place of the green, but the excess black is a problem. I need to find a way to get rid of it. Then I can input like 3d graphics/objects that almost interact with the actors...
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matt_magnone
Matt,
I fully understand your process and what you are doing. Unfortunately it will not yeild the best results unless your greenscreen/bluescreen is proportionate to your intentions. The shape of the blanket is not uniform in relation to your soccer-ball and the excess black around the soccor-ball is due to your image. Positioning it to stay within your mask will rid this. Another note, the chroma key for MSP is quite rudimentary. Notice the black artifacts being introduced by the computer workstation. Programs like FX Home Chromanator, Serious Magic Ultra Key, Adobe After Effects and Discreet Combustion are more suitable for this kind of work. Nick Jushchyshyn has written extra filters that all the above-mentioned programs include. These really help improve MSP's native compositing capabilities. You can find them at jushhome.com Hope this helps.
I fully understand your process and what you are doing. Unfortunately it will not yeild the best results unless your greenscreen/bluescreen is proportionate to your intentions. The shape of the blanket is not uniform in relation to your soccer-ball and the excess black around the soccor-ball is due to your image. Positioning it to stay within your mask will rid this. Another note, the chroma key for MSP is quite rudimentary. Notice the black artifacts being introduced by the computer workstation. Programs like FX Home Chromanator, Serious Magic Ultra Key, Adobe After Effects and Discreet Combustion are more suitable for this kind of work. Nick Jushchyshyn has written extra filters that all the above-mentioned programs include. These really help improve MSP's native compositing capabilities. You can find them at jushhome.com Hope this helps.
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matt_magnone
You wrote:
Is there a way that anyone can think of, to make a specific color transparent? If I could do that, I would be able to perfect this...
One can do this in their photo editor by creating a tga, psd, png, gif, etc... with background transparency checked. COOL3D has video overlay options, 32 bit AVI, etc... Also by using Video Paint, any added paint layer can be used in the matte process. As you can see there are many ways.
Is there a way that anyone can think of, to make a specific color transparent? If I could do that, I would be able to perfect this...
One can do this in their photo editor by creating a tga, psd, png, gif, etc... with background transparency checked. COOL3D has video overlay options, 32 bit AVI, etc... Also by using Video Paint, any added paint layer can be used in the matte process. As you can see there are many ways.
http://jushhome.com/nick/Tutorial/MSPColorDiff.asp
http://jushhome.com/nick/Tutorial/MSPImprovedComp.asp
The filters are located in the middle of both pages. Note that by using the color difference key technique, one can achieve even better results.
Moving path.
http://jushhome.com/nick/Tutorial/MSPImprovedComp.asp
The filters are located in the middle of both pages. Note that by using the color difference key technique, one can achieve even better results.
Moving path.
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matt_magnone
what I mean about the color transparency is not on the object. I know how to do that. Im talking about the excess black that the object does not cover. See, when I key that green basket, and put nothing in place (like the ball) you will see ALL BLACK. I can put the ball in there no problem, it's just that excess black that I need to rid. It's really hard keeping the ball exactly in there without that excess black showing from the keying. I dont know. This is too hard. The movies do it, so there has to be a way. Overlaying SUCKS. You move the camera and the overlaying object moves with it. How is it possible to get something like "The Hulk" accomplished??? I know its probably a very difficult process, but I doubt it's done by a simple OVERLAY... GRRRRRRRRRRR
Matt,
As I mentioned in my earlier post, one has many options for creating an alpha channel with images or video. This will eliminate the background around your object(soccer-ball). One really doesn't need the green/bluescreen compositing method to accomplish this. Shooting the soccer-ball against a greenscreen/bluescreen would be another approach.
One can somewhat achieve similar results to Hollywood but there really is no comparison.
As I mentioned in my earlier post, one has many options for creating an alpha channel with images or video. This will eliminate the background around your object(soccer-ball). One really doesn't need the green/bluescreen compositing method to accomplish this. Shooting the soccer-ball against a greenscreen/bluescreen would be another approach.
One can somewhat achieve similar results to Hollywood but there really is no comparison.
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matt_magnone
Matt,
I know the soccer-ball is not real. Shooting with a real object against a green/bluescreen is the way they do it in motion pictures. As for the image, its simple. Open any photo editor and snap to the outside boundary of your soccer-ball and make it an object. Thus allowing you to make it as a tga, gif, psd, png, etc... with background transparency checked. Then use it as an alpha overlay with your video. Then mask the hands in video paint and use the again mentioned ways of mask matte in your editor and you have it. To quote Terry, POOF.
I know the soccer-ball is not real. Shooting with a real object against a green/bluescreen is the way they do it in motion pictures. As for the image, its simple. Open any photo editor and snap to the outside boundary of your soccer-ball and make it an object. Thus allowing you to make it as a tga, gif, psd, png, etc... with background transparency checked. Then use it as an alpha overlay with your video. Then mask the hands in video paint and use the again mentioned ways of mask matte in your editor and you have it. To quote Terry, POOF.