Re: Currently-Available Highest-Quality Linear PCM Video?


Bob Myers wrote:
"Radium" <glucegen1@xxxxxxxxxx> wrote in message
news:1161127670.929976.69540@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi:

What are the sample rates and picture resolution [in pixels X pixels]
of the professional progressive [non-interlaced] linear-PCM video
format used today? I beleive linear-PCM video signals are used in
professional studios.

If you're talking about standard-definition television, and
the case of standard sampling formats for the conversion
and storage of "analog" video into digital form, the most
common international standard today is probably CCIR-601,
which uses a common 13.5 MHz sampling rate for both
525/60 and 625/50 video systems; this results in image
formats (not "resolutions," please) of 720 pixels x 480 lines
for the former and 720 x 576 for the latter.

What equation did you use to get the numbers 720, 480, and 576?

I don't know
what you mean by bringing "linear-PCM" into a question of
sampling rates and image formats.

Bob M.

Linear PCM is uncompressed PCM. Thats what I am talking about. Sampling
rate must be at least twice the highest frequency in the signal. Due to
physical conditions, it is safe to makes the sample rate at least 2.5x
the highest frequency signal.

In NTSC, the horizontal frequency is 15.734 kHz, the vertical frequency
is 60 Hz, and the color subcarrier frequency is 3.579545 MHz. The means
that the horizontal sample rate must be 39.335 khz or higher, the
vertical sample rate must be at least 150 hz, and the color subcarrier
sample rate must be no less than 8.9488625 mhz.

What is the pixel X pixel resolution -- or "format" if you wish -- of
today's first-class video signal? Surely it would have to be more than
720 X 576. My monitor is displaying a pixel X pixel -- or "screen area"
-- of 1280 X 1024 with 32-bit color. I am not sure of the frequencies
of my monitor.

Also, is there supposed to be a special difference between the first
number and the second number [such as 1280 X 1024 or 720 X 576]?


Thanks,

Radium

.