Difference between revisions of "Dictionary"

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===[[Aspect Ratio]]===
 
===[[Aspect Ratio]]===
 
The ratio of width to height of a video.
 
The ratio of width to height of a video.
===[[bitrate]]===
+
 
 +
===[[Bitrate]]===
 
The number of bits of data to be played per second.
 
The number of bits of data to be played per second.
 +
 
===[[Chroma]]===
 
===[[Chroma]]===
 
Greek for color, the part of a video file or signal that encodes the color portion.
 
Greek for color, the part of a video file or signal that encodes the color portion.
===[[codec]]===
+
 
A part of the program which understands a type of video or audio. ('''Co'''mpression/'''Dec'''ompression)
+
===[[Codec]]===
 +
A part of the program which understands a type of video or audio  (short for '''Co'''mpression/'''Dec'''ompression)
 +
 
 
===[[Decode]]===
 
===[[Decode]]===
 
To understand and play a file, VideoLAN needs to decode it. It does this with a decoder.
 
To understand and play a file, VideoLAN needs to decode it. It does this with a decoder.
 +
 
===[[Deinterlacing]]===
 
===[[Deinterlacing]]===
 +
 
===[[Demuxing]]===
 
===[[Demuxing]]===
 +
 
===[[Encode]]===
 
===[[Encode]]===
===[[MPEG-TS|TS]]===
 
Abbreviation for '''T'''ransport '''S'''tream.
 
  
 
===[[MPEG-ES|ES]]===
 
===[[MPEG-ES|ES]]===
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===[[FourCC]]===
 
===[[FourCC]]===
===[[framerate]]===
+
 
The number of frames of video displayed (or encoded to be displayed) per unit time, usually expressed in frames per second (fps) or Hertz (Hz). One Hertz is equivilant to one frame per second.
+
===[[Framerate]]===
 +
The number of frames of video displayed (or encoded to be displayed) per unit time, usually expressed in frames per second (fps) or Hertz (Hz). One Hertz is equivilant to one frame per second.
 +
 
 
===[[IDCT]]===
 
===[[IDCT]]===
 +
 +
===[[Keyframe]]===
 +
A [[frame]] of video which is stored as a complete image, not just as the changes from the previous image.
 +
 
===[[Motion Compensation]]===
 
===[[Motion Compensation]]===
 +
Part of the video compression process. New frames normally store changes in the image since the previous frame. If the scene is moving as a whole (such as panning), motion compensation moves the reference frame to line up with the new frame. This means that there are less changes to be stored since the previous frame, and so less data needs to be stored.
 +
 
===[[Muxing]]===
 
===[[Muxing]]===
 +
 
===[[Overlay]]===
 
===[[Overlay]]===
 
Displaying an image on top of the video
 
Displaying an image on top of the video
 +
 
===[[Packetizing]]===
 
===[[Packetizing]]===
 +
 
===[[Post Processing]]===
 
===[[Post Processing]]===
 +
 
===[[PCR]]===
 
===[[PCR]]===
 +
 
===[[MPEG-PS|PS]]===
 
===[[MPEG-PS|PS]]===
 
Abbreviation for '''P'''rogram '''S'''tream.
 
Abbreviation for '''P'''rogram '''S'''tream.
  
 
===[[PTS]]===
 
===[[PTS]]===
 +
 
===[[Sample rate]]===
 
===[[Sample rate]]===
Usually used with audio, the frequency at which a signal is digitally sampled, usually expressed in Hertz (Hz) or kiloHertz (kHz).  One Hertz is equivilant to one sample per second, One kiloHertz is a thousand (1000) Hertz.
+
Usually used with audio, the frequency at which a signal is digitally sampled, usually expressed in Hertz (Hz) or kiloHertz (kHz).  One Hertz is equivilant to one sample per second, One kiloHertz is a thousand (1000) Hertz.
 +
 
 
===[[Transcode]]===
 
===[[Transcode]]===
 
Transcoding is changing the format of a file.
 
Transcoding is changing the format of a file.
 +
 +
===[[MPEG-TS|TS]]===
 +
Abbreviation for '''T'''ransport '''S'''tream.

Revision as of 20:27, 18 January 2006

Some terms used in the area of Audio/Video and there meaning.

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Aspect Ratio

The ratio of width to height of a video.

Bitrate

The number of bits of data to be played per second.

Chroma

Greek for color, the part of a video file or signal that encodes the color portion.

Codec

A part of the program which understands a type of video or audio (short for Compression/Decompression)

Decode

To understand and play a file, VideoLAN needs to decode it. It does this with a decoder.

Deinterlacing

Demuxing

Encode

ES

An Elementry Stream, a single channel of audio, video or subtitles (without a container).

FourCC

Framerate

The number of frames of video displayed (or encoded to be displayed) per unit time, usually expressed in frames per second (fps) or Hertz (Hz). One Hertz is equivilant to one frame per second.

IDCT

Keyframe

A frame of video which is stored as a complete image, not just as the changes from the previous image.

Motion Compensation

Part of the video compression process. New frames normally store changes in the image since the previous frame. If the scene is moving as a whole (such as panning), motion compensation moves the reference frame to line up with the new frame. This means that there are less changes to be stored since the previous frame, and so less data needs to be stored.

Muxing

Overlay

Displaying an image on top of the video

Packetizing

Post Processing

PCR

PS

Abbreviation for Program Stream.

PTS

Sample rate

Usually used with audio, the frequency at which a signal is digitally sampled, usually expressed in Hertz (Hz) or kiloHertz (kHz). One Hertz is equivilant to one sample per second, One kiloHertz is a thousand (1000) Hertz.

Transcode

Transcoding is changing the format of a file.

TS

Abbreviation for Transport Stream.