|
The professional audio and video industry is known for complicated jargon. From acronyms to technical specifications to model numbers that seem to go on for miles, it has it all. Plus, terms like “asset management” mean different things to different companies – and sometimes have multiple interpretations within the same company! We hope this short glossary of terms can help you gain a better understanding of the technology behind the art and science of content production and delivery.
bandwidth – information-carrying capacity of a video signal or television channel
bit – short for binary digit, the smallest unit of data in a binary system (either a zero or one)
bit rate – amount of data that moves through a digital system, expressed as bits per second (bps)
byte – a group of bits processed together – the more bits in a byte, the more distinct values in that byte
More Info: A camcorder that offers 10-bit digital processing has 10 bits in a byte, which means each byte has 10 on/off switches, with “1” being on and “0” being off. In a binary system, you take the number two raised to the power of the number of bits. In this case, 210 is 1,024. In comparison, an 8-bit system, or 28, has 256 discrete values.
CCD – charged coupled device, a type of chip used in a camera to collect light and convert it to electrical impulses
CMOS – complementary metal oxide semiconductor, a chip technology for cameras that is more sensitive to light, produces less heat, and uses less power than CCDs
component – video cable that separates the video signal into three different signals
composite – video cable that send color and luminance information together
compression – a process that reduces the size of video files by removing redundant or noncritical data
frame sync – a digital buffer that continuously adjusts video signals for potential timing errors
image stabilization – circuitry in some camcorders and/or lenses that helps eliminate or reduce unsteadiness in handheld video footage
interframe – compression that removes redundant information from a group of pictures (video frames)
intraframe – compression that is self-contained within individual video frames
interlace scanning – a form of compression used in some video formats (including 1080i and NTSC) that builds frames from two interlaced fields of alternating lines
multicasting – simultaneous transmission of two or more program streams in a DTV signal
multi-viewer – allows a single monitor to display multiple video sources simultaneously
More Info: While some multi-viewers are simple screen splitters, many of today’s multi-viewers allow the user to edit the display layout, display a mix of asynchronous signal types (analog, HD-SDI, DVI, etc.), include time displays or timers, and even extend multi-view capabilities to additional monitors.
progressive scanning – a process used in some video formats (including 480p, 720p, and 1080p) where all lines of a frame are transmitted consecutively
S-Video – video cable that splits chrominance and luminance in the same cable
sampling – process of measuring an analog signal for conversion into a digital signal
More Info: Digital video is an approximation or representation of an analog audio or video signal. The quality of that digital signal is determined by the number of times an analog-to-digital converter looks at the original analog information (sampling frequency) and number of bits per sample (quantization).
transcode – digital-to-digital conversion of a video signal from one format to another
up/down/cross conversion – converting footage from one format to another format
More Info: Converting SD footage for use in an HD production is an example of upconversion, while converting HD footage to SD is downconversion. Cross conversion converts video from one HD format to another, such as 1080i to 720p.
|
