PCchips BKi810, Руководство пользователя

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WINDVD Documentation : Set the DMA Mode for the CD-ROM/DVD-ROM
NTSC and PAL
When the National Television Systems Committee (NTSC) prepared the standards for
commercial television broadcasting in the United States, Canada, Japan, and parts of
Central and South America, they decided on 525 lines of display at thirty frames per
second. In most of Europe, Australia, and parts of Central and South America, however,
the Phase Alteration Line (PAL) standard, 625 lines at 25 frames per second was used.
Aspect Ratios
Video can be stored on a DVD in any one of four ways:
 “ Standard ”, which has a ratio of 4 to 3,
 “ Wide screen ”, with a ratio of 16 to 9;
 “ Letterbox ”, which uses a 16 to 9 ratio but displays in a standard size screen;
 " Pan & scan ", which crops parts of the display out of the visible image in order to fit
into a standard size display.
DVD Audio
A DVD-Video disk can have up to 8 audio tracks, with each track being PCM, MPEG-2, or
Dolby Digital.
 PCM is uncompressed digital audio - the same format used on CDs. Using from one
to eight channels, it can be sampled at 48 or 96 kHz with 16, 20, or 24 bits per
sample.
 MPEG audio is multi-channel digital audio, using compression with sample rate of 48
kHz at 16 bits. Both MPEG-1 and MPEG-2 formats are supported.
 Dolby Digital is multi-channel digital audio, with a sample rate of 48 kHz at up to 24
bits. The bit rate is 384 Kb/s being the normal rate for 5.1 channels and 192 being the
normal rate for stereo, although most Dolby Decoders support a slightly higher bit
rate.
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