Bframe>B Frame:
An MPEG video frame type that provides bi-directional interframe compression. B frames derive their content from the closest I or P frames, one in the past and one in the future. B frames require greater computing power to produce than I or P frames. B frames enable compression rates of 200: 1. Robust MPEG encoders employ a combination of B, I, and P frame encoding.

B-Roll:
Stock footage acquired for miscellaneous needs.

Background:
In a multi-layered video effect, the "backmost" layer, on top of which other layers are keyed or composited.

Background Video:
1) Video that forms a background scene into which a key may be inserted. 2) A solid color video output generated by the background generator within a device, such as a production switcher, for use as background video in key effects.

Back Light:
1) A light source that illuminates a subject from behind, used to separate the subject from the background and give them depth and dimension. Back lights are often improperly applied or overlooked completely. 2) Also, a switch on some camcorders used to compensate exposure for situations where the brightest light is coming from behind the subject.

Bandwidth>Bandwidth:
Usually used in context to refer to the amount of data/unit of time that must move from one point to another - such as from CD-ROM to processor. The range of frequencies in a channel. The greater the bandwidth, the greater the capacity. Often used to state the capacity of analog circuits.

Base Light:
See Fill Light.

Betamax:
Consumer videocassette record/playback tape format using half-inch wide magnetic tape. Developed by Sony, Betamax was the first home VCR format.

Betacam>Betacam:
Portable, professional camera/recorder format developed by Sony. Betacam uses a component video system.

Betacam SP:
A superior performance version of Betacam. SP uses metal particle tape and a wider bandwidth recording system.

Bitmap:
Representation of characters or graphics by individual pixels arranged in row (horizontal) and column (vertical) order. Each pixel can be represented by one bit (simple black and white) or up to 32 bits (high-definition color). Also referred to as a raster image.

Bitmapped Graphics:
Images which are created with matrices of pixels, or dots. Also called raster graphics.

Bit Specifications:
Number of colors or levels of gray that can be displayed at one time. Controlled by the amount of memory in the computer's graphics controller card. An 8-bit controller can display 256 colors or levels of gray; a 16-bit controller, 64,000 colors; a 24-bit controller, 16.8 million colors.

Black a Tape:
The process of recording a black burst signal across the entire length of a tape. Often done before recording edited footage on the tape to give the tape clean, continuous video and sync and to insure there is no video already on the tape.

Black Box:
A single-purpose audio or video device, with its own set of I/O (input/output) connectors and typically its own control panel.

Blackburst > Black Burst:
A composite color video signal comprised of sync, color burst and black video. It is used to synchronize (genlock) other video sources to the same sync and color information. Black burst generators are used in video studios to "lock" the entire facility to a common signal ("house sync" or "house black").

Blacklevel > Black Level:
The voltage in a video signal which corresponds to black.

Blankinglevel > Blanking Level:
Also known as the pedestal, it is the voltage level produced at the end of each horizontal picture line which separates the portion of the video signal containing the picture information from the portion containing the synchronizing information. This voltage makes the electron beam "invisible" as it moves to draw the next visible line.

Blankinginterval > Blanking Interval (Horizontal & Vertical):
The horizontal blanking interval is the time between the end of one scanning line and the beginning of the next. The vertical blanking interval is the time between the end of one video field and the beginning of the next. Blanking occurs when a monitor's electron beam is positioned to start a new line or a new field. The blanking interval is used to instantaneously reduce the beam's amplitude so that the return trace is invisible. (See Vertical Interval Switching.)

Blue Screen:
A film or video technique in which an object or performer is taped against a blue-colored background. In post-production, the blue color is electronically removed, allowing images to be combined. Also, the film industry's term for chroma key.

BNC Connector:
A type of connector (Bayonet Neill-Concelman) used on some VCRs, video and RF equipment providing twist-lock capability.

Border:
The boundary between two merged video pictures, as created with chroma key or wipe effects.

BPP:
Bits Per Pixel. The number of bits used to represent the color value of each pixel in a digitized image.

BPS:
Bits Per Second. The number of bits transferred in a data communications system. Measures speed.

Brightness:
The balance of light and dark shades in an image.