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This article is from the DVD Formats FAQ, by jtfrog@usa.net (Jim Taylor) with numerous contributions by others.

1.19 Is DVD-Video a worldwide standard? Does it work with NTSC, PAL, andSECAM?

DVD-V has the same NTSC vs. PAL problem as videotape and laserdisc. The
MPEG video on DVD is stored in digital format, but it's formatted for one
of two mutually incompatible television systems: 525/60 (NTSC) or 625/50
(PAL/SECAM). There are three differences between discs intended for
playback on different systems: picture size and pixel aspect ratio (720x480
vs. 720x576), display frame rate (29.97 vs. 25), and surround audio (Dolby
Digital vs. MPEG). (See 3.4 and 3.6 for details.) Video from film is
usually stored at 24 frames/sec but is preformatted for one of the two
display rates. Movies formatted for PAL display are usually sped up by 4%,
so the audio must be adjusted accordingly before being encoded. All PAL DVD
players can play Dolby Digital audio tracks, but no NTSC players can play
MPEG audio tracks. PAL and SECAM share the same scanning format, so discs
are the same for both systems. The only difference is that SECAM players
output the color signal in the format required for SECAM TVs.

Some players will only play NTSC discs, some players will only play PAL
discs, and some will play both. All DVD players sold in PAL countries play
both. These multi-standard players partially convert NTSC to a 60Hz PAL
(4.43 NTSC) signal, which requires a PAL TV that can handle 60-Hz signals.
In this case the player uses the PAL 4.43 MHz color subcarrier encoding
format but keeps the 525/60 NTSC scanning rate. Most modern PAL TVs can
handle this kind of signal. A few multi-standard PAL players output true
3.58 NTSC from 525/60 NTSC discs, which requires an NTSC TV or a
multi-standard TV. Some players have a switch to choose 60-Hz PAL or NTSC
output when playing NTSC discs. In 1999, Samsung and others released
standards-converting players that convert from a 525/60 NTSC disc to
standard PAL output. Proper standards conversion requires expensive
hardware to handle scaling, temporal conversion, and object motion
analysis. Because the quality of conversion in DVD players is poor, using
pseudo-PAL output with a compatible TV provides a better picture. A very
small number of NTSC players can play PAL discs. External converter boxes
are available, such as the Emerson EVC1595 ($350).

A producer can choose to put 525/60 video on one side of the disc and
625/50 on the other. Most studios so far are including Dolby Digital tracks
along with the MPEG audio tracks on their PAL discs.

There are actually three types of DVD players if you count computers. Most
DVD PC software and hardware can play both NTSC and PAL video and both
Dolby Digital and MPEG audio. Some PCs can only display the converted video
on the computer monitor, but others can output it as a video signal for a
TV.

 

Continue to:

• prev: 1.18 What's a dual-layer disc? Will it work in all players?
• Index
• next: 1.20 What about animation on DVD? Doesn't it compress poorly?

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