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


Bob Myers wrote:
"Radium" <glucegen1@xxxxxxxxxx> wrote in message
news:1161306076.814071.181840@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

What uncompressed digital formats -- other than linear PCM -- exist?


Transmission or storage?

Both

Straight 24 bit/pixel RGB is
the most obvious example of an uncompressed digital
format, and it certain;y doesn't have to be encoded in
a PCM manner.

What is this RGB encoded? Or is RGB a format by itself. AFAIK, RGB
simply stands for Red, Green, and Blue. IIRC, RGB can be analog or
digital. So I doubt it is a digital format.

Most video -- whether analog or digital -- contains a red signal, a
green signal, and a blue signal. When all three colors are lit to full,
the result appears white. When none are lit, the result is black.

What is the file extension for the format you are talking about? Is it
..rgb? I doubt it

Just like audio files can have .wav, .pcm, and .raw extension, video
files should have an equivalent? What are the video equivalents of
those extensions?

Do you know
why linear PCM is used when it IS used?

It offers the best quality.

So your answer is "no, I really don't even know what
PCM is," right?

PCM is digital representation of an analog signal [such as video or
audio]





Please answer it, and then you will have cleared up your confusion
regarding "bit rate" and "pixel rate."

I never used the term "pixel rate". Pixel is the video equivalent of
channel. Stereo audio has two channels. Mono has only one.

No, the term "pixel" is used in a digital video context
interchangeably with "spatial sample." A "channel" is
something altogether different. Again, you clearly are
completely unfamiliar with the field in which you are trolling.

I am simply trying to find out the video equivalents of the terms used
in digital audio [e.g. "sample rate"]


I did use the term "sample rate". Sample rate is the rate at which an
analog signal is sampled via Pulse-Amplitude Modulation.


A "sample rate" is a completely independent question from
the modulation system used to encode or transmit information.
Sampled systems are no more required to use PAM than your
other new favorite buzzword, PCM.

If audio uses it, then what is a visual equivalent of it?



"Pixel rate" in video = "channel rate" in audio


Incorrect. The pixel rate in video is, if anything, most closely
related to the more general term "symbol rate" (or "baud
rate"), at least to the extent that until you define the number of
bits per pixel, the data rate (in bits/second or whatever equivalent
unit you like) cannot be determined. Similarly, "sample rate"
by itself does not determine the data rate.

I am well aware that sample-rate does not determine data-rate on its
own. Sample rate, bit-resolution, and number of channels, put together,
are what determine the data rate.

Data rate = sample rate X bit-resolution X number of channels

CD audio data rate: 1,411,200 bits per second
CD audio bit resolution: 16-bit
CD audio sample rate = 44,100 hz
# of channels in CD audio = 2

1,411,200 = 44,100 X 16 X 2


Both "channel rate" and "pixel rate" and totally meaningless.

That would come as a rather sizable surprise to a large number
of professionals (including myself) who deal with digital video
interface, etc., issues.

The rest of your post indicates that you should have been
able to answer the very questions you were trolling with. I
therefore fail to see any point to continuing this discussion.

Bob M.

.

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