An Image's Aspect Ratio represents a comparison of its width to height.
Two common video graphic aspect ratio are 4:3 (1.33:1), universal for standard-definition
video formats, and 16:9 (1.78:1), universal to high-definition television and European
Most DVDs have both AUDIO_TS and VIDEO_TS folder, but the AUDIO_TS holder is
usually empty. DVD-Audio would be stored in an AUDIO_TS folder but is a separate
format to DVD-Video.
AVI, which stands for Audio Video Interlace, is a multimedia container format
introduced by Microsoft in November 1992 as part of its Video for Windows technology.
Please beware the difference between a file format and a video codec.
In the case of AVI, as a "multimedia container", it does not specify
nor limit which codec should be used to encode the video and audio data,
but simply define how to combine a video stream and one or
several audio streams into a single file.
Bi-directional predictive pictures, which is commonly referred to as B frames.
They are not full frames and predicted by the previous frames and the next frames.
Bitrate represents the amount of information, or detail, that is stored per
unit of time of a recording. Bitrate calculations are typically made in kilobits per
seconds (kbps) or Megabits per seconds (Mbps).
Constant Bitrate (CBR)
Constant Bitrate (CBR) refers to video and audio encoding where the bitrate does not fluctuate.
Constant bit rate encoding means that the rate at which a codec's output data should be
consumed is constant.
In Audio, a channel is a stream of audio that is to be played by one speaker.
On the DVD, a chapter is a segment of a movie file. DVDs are separated into chapters
for easier navigation.
Closed GOP stands for Closed Group of Pictures. A closed GOP setting means that frames from the
current GOP cannot reference I frame from the previous GOP.
CRC (Cyclic redundancy check)
A CRC is an error-detecting code. It is a type of function that takes as input a data stream of
any length and produces as output a value of a certain fixed size.
The decibel (dB) is a logarithmic unit used to describe a ratio. It is used to measure
sound level, but it is also widely used in electronics, signals and communication.
Deinterlace is the process of creating a single frame from the two interlaced fields
of a video frame.
Demultiplexer (Demux) is a tool of splitting the file that contains both audio and video
data into separate files, each containing one element of the original file. Demuxing file
does not weaken the video nor audio quality, it just simply save them into separate files.
Dolby Digital (AC-3)
Dolby Digital (AC-3) is Dolby's third generation audio coding algorithm. It is the common
version containing up to six discrete channels of sound, with five channels for normal-range
speaker and one channel for the low-frequency effects.
DV is a video format used for digital video cameras.
DVD stands for Digital Versatile Disc. It is a popular optical disc storage media format.
Its main users are video and data storage.
A field is one of the many still images which are displayed sequentially to create the
impression of motion on the screen. Two fields comprises one video frame.
Field order refers to the choice of which field of an interlaced video signal is chosen
as the point at which video edits occur.
Frame rate (fps)
Frame rate is the measurement of the frequency at which individual images in the video
are displayed on the screen during playback. The television frame rate in US (NTSC) is 29.97
frames per seconds (fps). In many parts of Europe and Japan, the television standard is PAL
at 25 fps.
Group of pictures (GOP)
The GOP is a group of successive pictures within an MPEG-coded video stream.
Each MPEG-coded video stream consists of successive GOPs.
HDTV stands for High-Definition Television. It is high-resolution digital television
combined with Dolby Digital surround sound. The formats used in HDTV are:
- 720i : 1280x720 pixels interlaced
- 720p : 1280x720 pixels progressive
- 1080i: 1920x1080 pixels interlaced
- 1080p: 1920x1080 pixels progressive
Hertz (Hz) is the measurement for frequency or cycles per sound.
An I frame, or Key frame, is encoded as a single image without reference to any pictures.
Linear pulse code modulation (LPCM) is a method of encoding audio information digitally.
MBS stands for Multiple Bit Stream MPEG file in the Womble Editor.
Please read "MPEG MBS Scanner" for more detailed.
.mov is a file extension used by the Quick Time wrapped files.
MPEG Audio Stream with no video.
This is the MPEG-1 multiplexed data format.
It usually contains both compressed video and compressed audio data
formatted with additional information for audio and video
Compressed video using the MPEG-1 video compression standard (ISO/IEC-11172).
MPEG-2 Program stream
This is an MPEG-2 multiplexed data format (ISO/IEC-13818-1), very similar
to MPEG-1 Systems format with minor changes and mainly for
formatting MPEG-2 compressed video and audio data.
This is the format used by the Digital Video Disk (DVD) format.
MPEG-2 Transport stream
This is another MPEG-2 multiplexed data format (ISO/IEC-13818-1),
and it is mainly used for transmission of multi-program MPEG-2
compressed contents over telecommunication channels,
such as cable TV and satellite TV broadcasting.
Compressed video using the MPEG-2 video compression standard (ISO/IEC-13818-2).
MPEG-1 or MPEG-2 video elementary stream with no audio. MPEG-1 stream have a
.m1v extension and MPEG-2 stream have a .m2v extension.
Multiplexer (Mux) is a tool of joining video and audio to one file.
NTSC is the television system in use in the United States, Canada, Japan,
Mexico, Philippines, South Korea, Taiwan, and some other countries. It is
named for the National Television Standards Committee.
Video overlay is an technique used to display a video windows on a computer
display. This is done in order to speed up the video display.
P frame is a predicted frame. It is a video frame encoded relative to the past reference frame.
The past reference frame is the closest preceding reference frame.
PAL, short for Phase Alternation Line, is a colour encoding system used in large parts of the world.
Pixel Aspect Ratio (PAR)
Pixel aspect ratio (PAR) is the ratio of width to height of a single pixel.
RGB is an color model in which red, green, and blue. Every color in
the visible spectrum can be made from these three colors.
The sample rate is the number of samplers per second used to store a sound.
SVCD strands for Super Video CD. It is a format used for storing video on standard compact discs.
A function that will output a clip segment without changing any of the original content
and compression parameters.
These commands allow you to change a project back to a previous state.
VBR stands for Variable Bit Rate. VBR files vary the amount of output data per time
segment. VBR can be used to increase bitrate during high motion scenes in a video.
On a DVD disc, DVD movie files are stored in the VIDEO_TS folder.
VOB stands for DVD Video Object. It is a container format contained in the DVD-Video media.
WAV format is the standard Windows audio file format.
The YUV model defines a color space in terms of one luminance (Y) and two chrominance components (U and V).