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By supplying film studios with outstanding techniques for delivering soundtracks to an attentive audience,
DTS digital sound is now featured on virtually 100% of major Hollywood releases. Although the technology
used for motion pictures differs from that featured in consumer and professional audio music and home
theater systems, their DTS heritage means end users can enjoy sound that closely matches the original.
WMA
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WMA stands for Windows Media Audio. It is a proprietary format developed by Microsoft for audio streaming
and compression. WMA files, theoretically, has double the compression rate of MP3s, although this is
debatable.
Ogg Vorbis
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Ogg Vorbis is a new audio compression format. It is roughly comparable to other formats used to store and
play digital music, such as MP3, VQF, AAC, and other digital audio formats. It is different from these other
formats because it is completely free, open, and unpatented.
Ogg Vorbis has been designed to completely replace all proprietary, patented audio formats. That means
that you can encode all your music or audio content in Vorbis and never look back.
480p
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480 progressive; form of standard-definition digital television (SDTV) comparable to VGA computer displays
but not considered high-definition television (HDTV), though 480p is discernibly cleaner and slightly sharper
than analog television. The native resolution of DVD is 480p, but that resolution can be seen only if a DVD
player outputs a progressive-scan signal and the DTV has progressive-scan or component-video inputs; it is
also known as EDTV.
480i
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480 interlaced; form of standard-definition digital television (SDTV) that approximates the quality of analog
television but not considered high-definition television (HDTV). Even though the native resolution of DVDs is
480p, they are viewed at 480i on an NTSC analog television.
720p
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720 progressive. One of two currently used formats designated as high-definition television in the ATSC DTV
standard, this technology comprises 720 vertical pixels and 1,280 horizontal pixels. The p stands for
progressive, as opposed to interlaced, scanning, which is used in the other accepted HDTV standard, known
as 1080i. Contrary to myth, 720p is not inferior to 1080i; 720p has fewer lines but also has the advantages of
progressive scanning and a constant vertical resolution of 720 lines, making it better able to handle motion.
1080i
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1080 interlaced; one of two formats designated as high-definition television in the ATSC DTV standard, with
1,080 vertical pixels by 1,920 horizontal pixels. The i stands for interlaced, as opposed to progressive
scanning, used in the second HDTV standard, 720p. Contrary to myth, 1080i is not superior to 720p; 1080i
has more scanning lines but also suffers the disadvantages of interlaced scanning.
NTSC
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The NTSC (National Television Standards Committee) was responsible for developing, in 1953, a set of
standard protocol for television (TV) broadcast transmission and reception in the United States. Two other
standards - Phase Alternation Line (PAL) and Sequential Couleur avec Memoire (SECAM) - are used in
other parts of the world. The NTSC standards have not changed significantly since their inception, except for
the addition of new parameters for color signals. NTSC signals are not directly compatible with computer
systems.
An NTSC TV image has 525 horizontal lines per frame (complete screen image). These lines are scanned
from left to right and from top to bottom. Every other line is skipped. Thus it takes two screen scans to
complete a frame: one scan for the odd-numbered horizontal lines, and another scan for the even-numbered
lines. Each half-frame screen scan takes approximately 1/60 of a second; a complete frame is scanned
every 1/30 second. This alternate-line scanning system is known as interlacing.
PAL
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Phase Alternation Line (PAL) is the analog television display standard that is used in Europe and certain
other parts of the world. PAL is one of the three major TV standards together with the American National
Television Systems Committee(NTSC) color television system and the French Sequential Couleur avec
Memoire (SECAM). NTSC is also used in Japan. SECAM is used in countries of the former Soviet Union.
Like SECAM, PAL scans the cathode ray tube (CRT) horizontally 625 times to form the video image. NTSC
scans 525 lines. Color definitions between the systems vary slightly.
