"When it comes to converting TV systems, this is costly. A decent TV
standards converter is not cheap or easy to make. Converting a TV
standard to another (for example NTSC-PAL) conversion involves
changing of color coding, field rate and resolution.
The PAL to NTSC and NTSC to PAL converters boxes generally work in a
way that they take in composite video signal and output composite
video signal. Some commercial boxes also have other video signal
connection options (for example S-video).
The first color coding onversion is quite easy, but doing the latter
ones (field rate and resolution) properly is complicated if you want
to do it well. Conversion from NTSC to real PAL (or other way around)
may produce some stuttering in the image.
Some simplest commercial NTSC to PAL converter just convert the color
coding and leave all other video signal thing (number of scanlines,
signal timing, field rate etc.) as they are in NTSC signal. This kind
of converted signal is not standard PAL signal, but something which is
usually called "pseudo PAL" or "PAL60". Most modern PAL TVs can show
this signal nicely on the screen with colors, but you can't for
example record this signal to a PAL VCR."
http://www.epanorama.net/links/videosignal.html#conversion |
