Merging VCube, Руководство пользователя

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Appendices : Glossary Page 280
4.4.4
• Similar to 4:2:2 except that for every four luminance samples, the color channels are also sampled four
times.
A
• AES/EBU: Informal name for a digital audio standard established jointly by the AES and EBU organiza-
tions. The sampling frequency for this standard varies depending on the format being used; the sampling
frequency for D1 and D2 audio tracks is 48 kHz.
• alpha channel: is really a mask. It specifies how the pixel's colors should be merged with another pixel
when the two are overlaid, one on top of the other. It all allows transparencies inside a picture.
• aspect ratio: The ratio of television picture width to height. In NTSC and PAL video, the present standard
is 4:3.
• Autoconform: Where the Audio media files associated with an EDL are not available to the Pyramix PC,
Pyramix can control a tape deck or other device to import the required audio.
• AVI: an acronym for Audio Video Interleave, is a file format designed to store both audio and video data in
a standard package to allow its simultaneous playback. It's part of the Video for Windows technology.
B
• black level: The lowest transmittable luminance level that can occur during the active picture portion of a
video signal. When viewed on a monitor this signal level portrays the color black.
• buffer: A digital storage device used to compensate for a difference in the rate of flow of information or
the time of occurrence of events when transmitting information from one device to another.
C
• caption: Text or titles to be inserted in video.
• chrominance: That portion of the video signal, which contains the color information (hue and saturation).
Video picture information contains two components: luminance (brightness and contrast) and chromi-
nance (hue and saturation).
• clip: In desktop editing, a pointer to a piece of digitized video or audio that serves as source material for
editing.
• codec: Coder-decoder. A device that converts analog video and audio signals into a digital format for
transmission over telecommunications facilities and also converts received digital signals back into analog
format.
• Conform: Conforming is the process of making and positioning audio Cues in the Timeline from Audio
media files already present in a folder available to the Pyramix PC in conformity with an imported EDL
(Edit Decision List.) or video project, for example, AAF, Final Cut Pro or OMF.
• component: Video signal the keeps luminance and chrominance separate for better picture quality.
• composite: Video signal the combines luminance and chrominance in a single signal. Less expensive than
component video, but lower picture quality.
• compression: Reduction of the size of digital data files by removing redundant information (non-lossy) or
removing non-critical data (lossy). Also used to describe reduction in dynamic range.