One approach to creating a movie brush with masked shapes is to use a movie with an embedded alpha channel. The alpha channel for each frame can be used to define the shape of the object. If you already have a collection of images that contain alpha masks this is an easy approach to use. Or you could use Studio Artist Region Selection options or the Selective Color Matte Ip Op in a Paint Action Sequence (PASeq) to automatically generate an alpha channel for your collection of images if the individual objects are in front of a solid colored background. You would use the Source Alpha Brush option for the Brush Type parameter in the paint synthesizer when constructing your movie brush preset if your movie brush has an embedded alpha channel for masking the brush.
The goal here is to use the embedded alpha channel in the movie brush to define the shape and Fill From - Fill To mix for generating paint nibs, while using the RGB brush image to build the Fill From portion of the paint nib.
Another approach is to define the masked area in each frame as pure white (255,255,255). Studio Artist’s normal source brush masks out any portions of the brush that are pure white. You want to use the Paint Fill Setup control panel Fill Option popup option called ‘From’ to generate a hard masked brush. You would want the Fill From popup set to ‘Brush Image’ so that the non masked part of the movie brush image is passed through as the paint nib un-modified.
There are many different ways to colorize the individual movie brush images to more closely represent a specific paint color or to clone the main Studio Artist source image if that is what you are trying to do. One approach is to use ‘RGB Mapping’ Frame Modulation in the Source Brush control panel. This movie brush frame indexing is intelligent and tries to automatically choose the individual movie frame that most closely matches the color you are trying to paint with while you are drawing.
In the image example above i used a different coloring approach. I used ‘Cycle Forward’ Frame Modulation because i wanted to sequentially index through all of the movie brush frame images for maximum visual diversity in the painting. I use the Paint Fill Setup control panel Mod Type called ‘Mult Src Color’ with a Max Mod % of 80. This colorizes the brush image that is being used for the fill.
Using the Brush Load option for the Fill From parameter and doing the colorization in the Paint Brush Load control panel would be another option to colorize your movie brush images on the fly. Any of the Mean Shift or Fixed Color mapping algorithms in the Paint Brush Load control panel will colorize the Source Brush. You would want to use the Image Processing option for the Brush Load Type paramter with the Brush as the Source.
There were a daily effect blog posts on re-colorizing movie brushes if you want more information on this paint Brush Load control panel approach to colorizing a movie brush, which can be found here.
Check out the photo mosaic and movie brush tutorials on Studio Artist 3.5 tutorial disc #2 for more information on how to take a folder of images and convert them into a movie file you can use as a movie brush. Remember, you can always use the Video training Guide pdf documentation to find a specific Studio Artist video tutorial.
Hopefully these tips will jump start your imagination regarding how you could personalize the Studio Artist movie brush capabilities to create custom object masked movie brush paint presets for your own artwork. By customizing the movie brush imagery you could create an unlimited range of different visual styles to suit the mood you are trying to convey in your own paintings.