Search results
Results from the WOW.Com Content Network
In computer graphics, alpha compositing or alpha blending is the process of combining one image with a background to create the appearance of partial or full transparency. [1] It is often useful to render picture elements (pixels) in separate passes or layers and then combine the resulting 2D images into a single, final image called the composite.
The actor can also be filmed against a chroma-key background and inserted into the background shot with a distortion effect, in order to create a cloak that is marginally detectable. [ 13 ] Difficulties emerge with blue screen when a costume in an effects shot must be blue, such as Superman 's traditional blue outfit.
a background pixel, b; a composited adetpixel, c; and α, the opacity value of the foreground pixel. (α = 1 for an opaque foreground, α = 0 for a completely transparent foreground). A monochrome raster image where the pixel values are to be interpreted as alpha values is known as a matte.
GIF animation of an Apollonian sphere packing with transparent background. Transparency in computer graphics is possible in a number of file formats.The term "transparency" is used in various ways by different people, but at its simplest there is "full transparency" i.e. something that is completely invisible.
Another approach (more suited to hardware acceleration) is to render the view from ¯ by rasterizing black geometry against a white background and taking the (cosine-weighted) average of rasterized fragments. This approach is an example of a "gathering" or "inside-out" approach, whereas other algorithms (such as depth-map ambient occlusion ...
Mattes are used in photography and special effects filmmaking to combine two or more image elements into a single, final image. Usually, mattes are used to combine a foreground image (e.g. actors on a set) with a background image (e.g. a scenic vista or a starfield with planets). In this case, the matte is the background painting.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Order-independent transparency (OIT) is a class of techniques in rasterisational computer graphics for rendering transparency in a 3D scene, which do not require rendering geometry in sorted order for alpha compositing.