ABSTRACT
Compositing programs differ from digital imaging programs in that they are designed for animation. As such, it is necessary to place keyframes that define the values of parameters at different frames along the timeline. The keyframes define transformations, such as translate, scale, and rotate, and allow various filters to change their qualities over time. The bounding box, visible in the Viewer panels as a dotted white box, defines the area of the frame that the program considers to have valid data. Initially, the bounding box fits itself to the project resolution. Any node that applies a transform includes a Filter parameter. The Filter parameter drives the node's filter interpolation, which is necessary when the output is rotated, enlarged, or reduced. Impulse, creating stair-stepping along the edge. Bilinear is a type of filter that uses a triangular-shaped curve function. Bilinear filters are able to average the color values of surrounding original pixels by weighting values based on distance to new pixel.
