Eyeon:Manual/Tool Reference/Primatte/Part2
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Contents
Part 1
2. Accessing Primatte from Fusion
Part 2
- 4a. Effect of Spill (+/-) Repeatable Sampling
- 4b. Effect of Matte (+/-) Repeatable Sampling
- 4c. Effect of Detail (+/-) Repeatable Sampling
- 5a. Complemental Spill Replacement (Complement)
- 5c. Defocus Spill Replacement (Image)
- 5b. Solid Color Spill Replacement (Color)
7. External Garbage Matte Input
Part 3
8. Primatte Tools and Buttons Descriptions
- 8a. Primatte Tab
- 8b. Fine Tuning Tab
- 8c. Replace Tab
- 8d. Degrain Tab
- 8e. Matte Tab
- 8f. Sampling Selectors
Part 4
9. More About the Primatte Polyhedral Slicing Algorithms...
4. Repeatable Sampling Tools
Most of the Primatte operations are done using a 'mouse sampling' operation. The only exceptions are the Fine Tuning operational mode and its sliders. The Fine Tuning operation gives a continuous valuator for fine-tuning but some of the sliders are not often used because results are often unpredictable or not subtle enough. Note: Another weak point in previous versions of Primatte is the lack of functionality to attenuate and thicken the existing matte density. This version of Primatte offers a more intuitive, easy-to-use and powerful user interface called Repeatable Sampling.
In addition to the conventional Primatte operation modes previously mentioned, six other tools are added:
- Spill (+)
- Spill (-)
- Matte (+)
- Matte (-)
- Detail(+)
- Detail(-)
The Spill Sampling Tools
- Using the Spill (+) and Spill (-) modes, you can gradually remove or recover the spill intensity on the foreground object by sampling the referenced color region repeatedly. The conventional Spill Sponge tool removes the spill component in a single action at one level and did not allow sampling the same pixel a second time. Even though just a small amount of spill needed to be removed, the spill sponge removed a preset amount without allowing any finer adjustment.
Effect of Spill (+/-) Repeatable Sampling
- Using the zoom and pan capabilities of the Fusion application, zoom into an area that has some blue edges and click on a pixel with some spill on it. Repeated clicking will incrementally remove the spill. Continue this operation until the desired result is achieved.
The Matte Sampling Tools
- The Matte (+) and Matte (-) modes are used to thicken or attenuate the matte information. If you want a thinner shadow on a foreground object, you can use the Matte (-) mode as many times as you like to make it more transparent. On the other hand, you can use the Matte (+) mode to make the matte thicker in that color region.
Effect of Matte (+/-) Repeatable Sampling
The Detail Sampling Tools
- The Detail (+) and Detail (-) modes are a refined version of Clean Background Noise and Restore Detail. For example, when you see some dilute noise in the backing area but don't want to remove it completely because it affects some fine detail in a different area, try using Detail (-). It will attenuate the noise gradually as multiple samples are made on the pixel. You should stop the sampling when important fine details start to disappear.
Effect of Detail (+/-) Repeatable Sampling
5. Spill Replacement Options
The proper processing of spill on foreground objects is one of the many useful features of Primatte. You can move between these three modes to see how they affect the image clip you are working with. The three methods are as follows:
- -Complemental Spill Replacement (Complement)
- -Defocus Spill Replacement (Image)
- - Solid Color Spill Replacement (Color)
Complemental Replacement Mode
- This is the default spill replacement mode. This mode will maintain fine foreground detail and deliver the best quality results. If foreground spill is not a major problem, this mode is the one that should be used.
Complemental Replacement Mode Maintains Fine Detail.
- The Complemental Replacement mode is sensitive to foreground spill. If the spill intensity on the foreground image is rather significant, this mode may often introduce serious noise in the resultant composite.
Solid Color Replacement Mode
Defocus Replacement Mode
- The Defocus Replacement mode uses a defocused copy of the background image to determine the spill replacement colors instead of a solid palette color or just the complement color. This mode can result in good color tone on the foreground object even with a high contrast background. As in the example below, spill can even be removed from frosted glass using this feature and still retain the translucency. - On the negative side, the Defocus Replacement mode sometimes results in the fine edge detail of the foreground objects getting lost. Another problem could occur if the user wanted to later change the size of the foreground image against the background. Since the background/foreground alignment would change, the applied color tone from the defocused image might not match the new alignment.
Blue Suppression of a Frosted Glass Object
Solid Color Replacement Mode
- In the Solid Color Replacement mode, the spill component will be replaced by a 'user defined' palette color. While the Complemental Replacement mode uses only the backing color complement to remove small amounts of spill in the original foreground, the Solid Color Replacement mode tries to assuage the noise using the 'user defined' palette color. Changing the palette color for the solid replacement, the user can apply good spill replacement that matches the composite background. Its strength is that it works fine with even serious blue spill conditions.
Smooth Spill Processing with Solid Color Replacement
- On the negative side, when using the Solid Color Replacement mode, fine detail on the foreground edge tends to be lost. The single palette color sometimes cannot make a good color tone if the background image has some high contrast color areas.
6. Matte Blur Inward Feature
A new method of defocusing or blurring the matte has been added. This new feature can be set to only blur inward toward the center of the foreground subject. The conventional Primatte defocus feature affected the matte edges in both directions (inward and outward) and sometimes introduced a halo artifact around the object edge in the composite view. This was most evident when using the Complemental Replacement mode. With the Blur Inward switch ON, the matte defocus functions only in the inward direction of the foreground subject (toward the center of the white area). The final result is that it removes small and dark noise in the backing area without picking them up again in the Clean Background Noise mode and sometimes results in softer, cleaner edges on the foreground objects.
7. External Garbage Matte Input
Primatte now accepts a hand-drawn matte as the external matte to hide the unnecessary garbage like light arms, microphones and other undesirable foreground object. Areas that are white in the garbage matte clip will take the pixels from the background and areas that are black will be from the composite image. This External Garbage Matte can also be inverted.
