- AVI
Audio Video Interleaved - A multimedia file format for storing sound and moving pictures
in RIFF format developed by Microsoft. An AVI file can use different codecs and formats so
there is no set format for an AVI file unlike for example standard VCD video which sets a
standard for resolution, bitrates, and codecs used.
- MPEG-1
An ISO/IEC (International Organization for Standardization/ International Electrotechnical
Commission) standard for medium quality and medium bitrate video and audio compression. It
allows video to be compressed by the ratios in the range of 50:1 to 100:1, depending on
image sequence type and desired quality. The encoded data rate is targeted at 1.5Mb/s -
this was a reasonable transfer rate of a double-speed CD-ROM player (including audio and
video). VHS-quality playback is expected from this level of compression. The Motion
Picture Expert Group (MPEG) also established the MPEG-2 standard for high-quality video
playback at a higher data rates. MPEG-1 is used in encoding video for VCD.
- MPEG-2
An encoding standard designed as an extension of the MPEG-1 international standard for
digital compression of audio and video signals. MPEG-1 was designed to code progressively
scanned video at bit rates up to about 1.5 Mbit/s for applications such as CD-i. MPEG-2 is
directed at broadcast formats at higher data rates; it provides increased support for
efficiently coding interlaced video, supports a wide range of bit rates and provides for
multichannel surround sound coding such as PCM, Dolby Digital, DTS and MPEG audio.
MPEG / VCD / SVCD/ DVD
MPEG is the dominant file format used to create VCD, SVCD and DVD. This high quality
compressed format can be used across all platforms. VCD, SVCD and DVDs accept MPEG files
that conform to their respective standards. MPEG files differ in many parameters that
characterizes the MPEG format.
The table below lists down the format in which MPEG files are made by Video Workshop
depending on the type of video disc.
| Video
Disc |
MPEG
Format (Standard) |
| Disc Format |
Picture Standard |
Disc Type |
MPEG Type |
Dimension (pixels) |
Frame Rate (FPS) |
Video Bitrate (Kbps) |
Audio Bitrate (Kbps) |
| VCD |
NTSC |
CD |
MPEG 1 |
352 x 240 |
29.97 |
1152 |
224 |
| VCD |
PAL |
CD |
MPEG 1 |
352 x 288 |
25 |
1152 |
224 |
| SVCD |
NTSC |
CD |
MPEG 2 |
480 x 480 |
29.97 |
2500 |
192 |
| SVCD |
PAL |
CD |
MPEG 2 |
480 x 576 |
25 |
2500 |
192 |
| DVD |
NTSC |
DVD |
MPEG 2 |
720 x 480 |
29.97 |
6000 |
224 |
| DVD |
PAL |
DVD |
MPEG 2 |
720 x 576 |
25 |
6000 |
224 |
- NTSC
Abbreviation of National Television Standards Committee.
The NTSC is responsible for setting television and video standards in the United States
(in Europe and other parts of the world, the dominant television standards are PAL and
SECAM). The NTSC standard for television defines a composite video signal with a refresh
rate of 60 fields (half-frames interlaced) per second. Each frame contains 525 lines and
can contain 16 million different colors. The resolution of an NTSC VCD is 352x240 pixels,
an NTSC SVCD is 480x480, and an NTSC full D1 DVD is 704 or 720 x 480.
- PAL
Short for Phase Alternating Line, the dominant television standard
in Europe. The United States uses a different standard, NTSC. PAL delivers 625 lines at 50
fields (half-frames interlaced) per second. The resolution of a PAL VCD is 352x288 pixels,
a PAL SVCD is 480x576, and a PAL full D1 DVD is 704 or 720 x 576.
- ASF
Advanced Streaming Format (ASF): This file format stores audio and video information, and
it is specially designed to run on networks like the Internet. This file format is a
highly flexible and compressed format that contains streaming audio, video, slide shows,
and synchronized events. When you use .asf files, content is delivered to you as a
continuous flow of data. You no longer have to wait for your audio and video files to
fully download before you start to view them. When an AVI file is compressed and converted
to an .asf file, the file begins playing after only a few seconds. The file can be
unlimited in length and can run over Internet bandwidths.
- MOV,QT (Quick Time)
A digital video Format standard developed by Apple Computer for Macintosh (Mac OS) and
Windows operating systems.
- RM
Real Media streaming format for audio/video data.
- MP4
A container format allows you to combine different multimedia streams
(most of the time audio and video) into one single file.
Multimedia containers are for example the well known AVI (.avi), MPEG (.mpg, .mpeg),
Matroska (.mkv, .mka), OGM (.ogm), Quicktime (.mov) or Realmedia (.rm, .rmvb)
MP4 is the global file extension for the official container format defined in the MPEG-4
standard (ISO 14496-14)
MP4 is streamable and supports all kinds of multimedia content (multiple audio-, video-,
subtitlestreams, pictures, variable-framerates, -bitrates, -samplerates...) and advanced
content (officially called "Rich Media" or "BIFS") like 2D and 3D
animated graphics, user interactivity, DVD-like menus... - next to nothing handled by the
often used AVI
- PSP MP4
A file format developed for PlayStation Portable (PSP).
- iPod MP4
A file format developed for iPod video.
- 3GP
The mpeg4 based video format used in mobile terminals, like cell phones.
| Cellular
Phone Model |
Video
Output |
Audio
Output |
| Sony Ericsson
W800i |
Bit rate: 500kbps
Format: h263
Size: 176x144 pixel
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
| Sony Ericsson
K750i |
Bit rate: 104kbps
Format: mpeg4
Size: 176x144 pixel
Frame rate: 25.00fps |
Format: mpeg4aac
Sample rate: 22050Hz
Channels: Mono |
Nokia
6230 |
Bit rate: 118kbps
Format: mpeg4
Size: 128x96
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Nokia
6620 |
Bit rate: 79kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Nokia
6630 |
Bit rate: 138kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Motorola
V710 |
Bit rate: 78kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Motorola
V635 |
Bit rate: 216kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Motorola
V547 |
Bit rate: 122kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Samsung
D. 500 |
Bit rate: 73kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
Sanyo
5600 |
Bit rate: 96kbps
Format: h263
Size: 176x144
Frame rate: 25.00fps |
Format: amr_nb
Sample rate: 8000Hz
Channels: Mono |
- Flash Video (FLV)
SWF is not the only Flash format. FLV files
(Flash Video Files) are a binary file format that delivers "bitmapped"
video, limited to one video and one audio stream per file, over the Internet to the
Macromedia Flash Player version 7. FLV content may also be associated with SWF files by
ActionScript external references. FLV format can also imported
into Macromedia Flash Authoring tool.
Unlike SWF format, FLV do not have maximum of 16000
frames limitation and ideally for large video file
size.
- Frame
Television:
A set of scanlines in video to make a complete picture. If the video is interlaced the
frame consists of both of the interlaced fields (half frames). If the video is progressive
the the frame is made up of one continuous scan from top to bottom. The number of
scanlines vary in a frame depending on the TV system used. PAL50 uses 625 scan lines,
NTSC60 (US) 525.
Video Encoding:
A frame is one picture but depending on the encoding scheme it may not be a complete
picture (I-Frame) but dependent on frames before or after the current frame (P-Frame,
B-Frame).
- MP3
MP3 is an acronym for MPEG-1 (or MPEG-2) Layer 3 audio encoding (it is not an acronym for MPEG3). MP3 is a popular compression
format used for audio files on computers and portable devices.
The compression in MP3 works on the basis of a "psychoacoustic model" which
means that parts of the audio that human ears cannot detect are discarded by the encoder.
Although this is a LOSSY process, it can yield very high quality audio files are
relatively high compression rates.
A typical MP3 file encoded at 128 kbit/s (12:1 compression) is near CD quality.
- Wave
Wave is the standard form for uncompressed audio on a PC. Since a wave file is
uncompressed data - as close a copy to the original analog data as possible - it is
therefore much larger than the same file would be in a compressed format such as mp3 or
RealAudio. Audio CDs store their audio in, essentially, the wave format. Your audio will
need to be in this format in order to be edited using a wave editor, or burned to an audio
CD that will play in your home stereo.
- Sample Rate
The sample rate of an audio recording partially determines the overall sound
quality. In the recording process, audio samples are saved to memory or disk; the rate
each sample of audio input is recorded per second is the sample rate. The sample rate is
measured in Hertz (Hz - cycles per second) and Kilohertz (kHz - thousand cycles per
second). CD quality audio has
a sample rate of 44100Hz, 16-bit (resolution) and stereo (channels). The most common
sample rates are 11, 22 and 44kHz, with most recording software supporting sample rates
from 6kHz up to 192kHz. Like early footage filmed at a low frame rate looks flickered and
robotic, the quality of an audio recording decreases as the sample rate is lowered. For
audio recordings destined to be encoded to MP3, 22kHz is considered acceptable.
- Bit Rate
Bit rate is the amount of information (bits) transferred in
a second ('bps' is the abbreviation of bits-per-second). Bitrate or
Bit Rate is the average number of bits that one second of video or audio data will
consume. Higher bitrate means bigger file size and generally better video or audio quality
while lower bitrate means lower file size but worse video or audio quality. Some bitrate
examples in common video and audio files:
MP3 about 128 kbps (kilobits per second)
VCD about 1374 kbps
DVD about 4500 kbps
DV about 25 Mbps (megabits per second).
- bps
Bits per second. A unit of data rate
- fps
Frames per second. A measure of the rate at which pictures are shown for a motion video
image. In NTSC and PAL video, each frame is made up of two interlaced fields.
- Codec
An acronym for "compression/deccompression", a codec is an algorithm or
specialized computer program that encodes or reduces the number of bytes consumed by large
files and programs. Files encoded with a specific codec require the same codec for
decoding. Some codecs you may encounter in computer video production are Divx, MPEG-1,
MPEG-2, Xivd, DV type 1 and type 2 for video and MP3 for audio.
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