iSignager-800WL-N270 Digital Signage Player
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A.1 Overview of Video Formats
A.1.1 MPEG-1
MPEG-1 is a standard used to compress audio and video (AV) digital data. MPEG-1
defines a group of AV coding standards agreed upon by MPEG (Moving Picture Experts
Group). MPEG-1 video is used by the Video CD format. The output quality at usual
VCD bit rates is roughly that of a VCR. MPEG-1 audio layer 3 is the full name for the
popular audio format MP3. The MPEG-1 AV format was later extended into the MPEG-2
and MPEG-4 formats. These extensions allow for greater compression for the same size
of data.
A.1.2
MPEG-2
MPEG-2 is a standard used primarily to compress audio and video (AV) digital data.
MPEG-2 is the designation for a group of coding standards for AV, agreed upon by MPEG
(Moving Pictures Experts Group), and published as the ISO/IEC 13818 international
standard. MPEG-2 is typically used to encode audio and video for broadcast signals,
including direct broadcast satellite and Cable TV. MPEG-2, with some modifications, is
also the coding format used by standard commercial DVD movies.
A.1.3
MPEG-4
MPEG-4 is a standard used primarily to compress audio and video (AV) digital data. It is
the designation for a group of audio and video coding standards and related technology
agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG). The uses for the
MPEG-4 standard are web (streaming media) and CD distribution, conversational
(videophone), and broadcast television, all of which benefit from compressing the AV
stream.
A.1.4
DivX® and XviD
DivX is a video codec created by DivX, Inc. which has become popular due to its ability to
compress lengthy video segments into small sizes while maintaining relatively high visual
quality. DivX uses lossy MPEG-4 Part 2 compression, where quality is balanced against
file size for utility.
