P Frame: An MPEG encoding method using a predictive algorithm to take into account information that is common among adjacent frames. P frames predict the difference between the current frame and the closest preceding I or P frame to minimize the amount of data that needs to be coded for each frame. P frame encoding is used in conjunction with I and B frame encoding.

PAL: Phase Alternating Line. Video format used in most of Western Europe, Australia and other countries.

Paint: The process of using a computer system to apply graphics, textures, shapes and colors to create or modify video images. Paint is used to create video slides, backgrounds, and other effects.

PAL Format: 625 lines of resolution at 25 frames per second.

PAL-M: A version of the PAL system used only in Brazil.

Panasonic 5-pin edit control: Panasonic's wired edit control protocol. See CONTROL-M.

PCM: Pulse Code Modulation. The most common method of encoding an analog signal into a digital bit stream. A digitization technique, not a universally accepted standard.

Pedestal: The pedestal is a small DC voltage step within the video signal indicating a picture's black level and is used as the reference in a standard video signal for white level and all gray levels.

Phase Error: A change in the color subcarrier signal which moves its timing out of phase, i.e., it occurs at a different instant from the original signal. Since color information is encoded in a video signal as a relation between the color subcarrier and the color burst phase, a deviation in the color subcarrier phase results in a change in the image's hue.

Picture Sharpness: The fine details in a video picture. A picture appears sharp when it contains fine details and has good contrast. Picture sharpness is easily lost during the recording/playback process. Advanced video enhancement equipment is used to improve picture sharpness, especially contrast, and can precompensate for potential losses which might alter an image during processing.

PIP: Picture In Picture. A digital special effect in which one video image is inserted within another allowing several images to share a single screen.

Pixel: An abbreviation for picture element. The minimum raster display element, represented as a point with a specified color or intensity level. One way to measure picture resolution is by the number of pixels used to create the image.

Playback: The process whereby a videotape is displayed on a monitor. During playback, use of a video processor can be used to alter, enhance, correct or restore a signal.

PLV: Production Level Video. An asymmetric compression algorithm. Source video is sent to a Digital Compression Facility (DCF), where a supercomputer processes it frame-by-frame to provide superior image color and quality.

Post-Production: All production work done after the raw video footage and audio elements have been captured. Editing, titling, special effects insertion, image enhancement, audio mixing and other production work is done during post-production. Videonics equipment is ideally suited for use in post-production.

Posterization: Special effect in which the picture is reduced to a small number of colors or luminance levels removing any fine gradations of color and brightness resulting in an oil painting or poster effect.

Pre-Enhancement: In many situations, video losses can be anticipated, allowing signal pre-compensation in a way that partially corrects for the losses. (See Line Compensation.)

Preview Bus: A processor function allowing the operator to select any incoming video source for viewing prior to actual use. Typically, each signal can be previewed on its own monitor. This is an effective method to check work before going "on the air."

pre-visualization: A method used in feature film development which utilizes Virtual Sets by placing actors in scene mock-ups to test the viability of a set.

Primary Colors: The basic colors used in TV and video systems of red, green and blue that when combined can produce a broad spectrum of other color.

Production House: The facility in which video programs are edited.

Program Bus: Similar to the preview bus in concept except that the resulting output is the final signal which goes "on the air."

PX64: Similar to MPEG, but adapted to slower bit rate. Typically used for video conferencing over an ISDN phone line.