Besides the time difference, what are the differences in the way
Standard Play (SP) and Long Play (LP) modes write?

Are the data different and/or track spacing different - what else?

Rick Merrill wrote:
The ONLY difference is information content.

Video and audio are written to DVD in "frames" and the playback of
these is in frames per second. An hour of SP, LP, XLP, or SXLP or
whatever, takes the same number of frames per scheme - NTSC or PAL or
whatever. So, what's different is how many bits of information make
up a frame. The more bits (the more info) the more opportunity for a
better picture.

MPEG2 is compressed video. No matter the bit rate, the playback
picture must be recomposed algorithmically from the info available.
Fewer bits per frame, the more the algorithm has to "imagine" what's
missing.

"Bill's News" <BillsNews@pcmagic.net> wrote in message
news:43efbfef$1_5@newsfeed.slurp.net...
Not correct.
Not correct.

"Alpha" <none@none.net> wrote in message
news:11uvices7pq3pe3@corp.supernews.com...
Actually, Bill's explanation is accurate, somewhat odd and
not the way most of us would look at it, but accurate.

If it is the "written to DVD in 'frames'", that bothers you,
consider that it is no less (or more) accurate to say that the Audio
and Video is written to DVD in streams. Or to go the other way;
written to DVD in fields (if interlaced).

In fact the "Bits per Frame" as related to MPEG compression
is an important concept often overlooked. The way he is
presenting it is quite workable, as there are few of us who need
to optimize at the GOP frame level, so treating each frame as
equals is no big sin.

That a binary manipulation algorithm can "Imagine" what is
missing" may be a little anthropomorphic, but works for a
general description.

Luck;
Ken

"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:0eednZ7R4K2VFW3enZ2dnUVZ_tWdnZ2d@giganews.com ...
no concept of frames at the bit stream output side. On the input side, of
course one can consider the FFT to be based on frames of samples. I am
aware of the video terms I, B, P frames, etc. Since the output is often
VBR, the output has 'variable frames' then. I think the term stream is most
accurate! The differences in video and audio concepts of time in
compression for Mpeg Layer II and above is what makes sync so difficult.

"When I make a word do a lot of work like that," said "Ken Maltby"
<kmaltby@sbcglobal.net>, "I always pay it extra."

MPEG streams are written to DVD in frames, not fields. Interlacing is
handled (or not) in the player.

GOP frame level? A GOP is typically 12 or 15 frames.

I'm all for anthopomorphism. I've found it a valuable tool in
expalining what a computer is doing to people who don't understand
computers :-)

--
Humbug

"When I make a word do a lot of work like that," said Rick Merrill
<rickZERODOTmerrill@NOSPAMgmail.com>, "I always pay it extra."

The way it is written is exactly the same for both modes. The
difference is in the compression ratio.

Exactly how the compression ratio affects programme quality depends on
the programme content.

For a lot of programmes, you may not notice any considerable
difference between SP and LP - but if there is a lot of fast movement,
e.g. sports programmes, you may notice more artifacts if the bit-rate
is too low.

--
Humbug

"Humbug" <humbug@tofee.net> wrote in message
news:6e32v152e5eke9tmdd6k1822nr6rd2rpqa@4ax.com...
The computer does not imagine...the math is clear and the results evident.
A better verb is 'predict' and another is 'interpolate.'

I am not suggesting making things more difficult to understand than
necessary, however:

If we continue to water down everything ad infinitum, we will have what we
are now getting: The most scientifically illiterate country in the world.

"When I make a word do a lot of work like that," said "Alpha"
<none@none.net>, "I always pay it extra."

I guess that you are American, then.

--
Humbug

"Humbug" <humbug@tofee.net> wrote in message
news:5ca2v1p4vvqn6ffq3snit74euum7pfvrbf@4ax.com...
yes

We have all those immigrants to draw on, which makes
it us Americans who are still providing the largest share of
scientific development. Of course many of the Americans,
who are doing so, were born in another country.

Luck;
Ken

P.S. Literacy, as it relates to specialized knowledge, is to
some extent a matter of what's useful in a person's life and
what's only effectively trivia. I would expect my Doctor, my
Auto Mechanic, and my Grocer to be "literate" in a different
set of and level of "literacy". There are those who only
require a limited understanding to meet their needs/ interests.

"When I make a word do a lot of work like that," said "Ken Maltby"
<kmaltby@sbcglobal.net>, "I always pay it extra."

I remember that. It was called the Brain Drain.

--
Humbug (who went to school with Tim Berners-Lee)

On Mon, 13 Feb 2006 15:15:10 -0800, "Alpha" <none@none.net> wrote:

And when the system fails to re-create the image properly, "imagine" seems
a good enough way to describe how the artifacts were arrived at. These
technologies are not mature, IMO, and what's clear and evident is that
there's a lot of "winging it" going on.

So you couldn't get a job writing algorithms if your knowledge of these
things stopped at this level. So what? Do you know how to do everyone's
else's job? Why should everyone know how to do yours?






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On Mon, 13 Feb 2006 23:13:54 +0000, Humbug <humbug@tofee.net> wrote:

Or, to put it another way, a given disc has a maximum limit on the amount
of data it holds. Since the video is recorded using lossy compression, it
is possible to decide to use more or less data per unit of time. It's then
up to the player to reconstruct the video based on the data it receives.
More data = better reconstruction.

I don't have the exact figures handy, but suppose SP uses 8 million bits
per second and LP uses 4 million bits per second. Then you can see that it
will take twice as long to fill up a disc at LP, but there will be only
half the amount of information available to reconstruct the video. Whether
this difference is visible depends on the quality of the encoding and on
the quality of the reconstruction as well as the nature of the images.






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In article <11v24o26me5p1ee@corp.supernews.com>, Alpha <none@none.net> wrote:
What 'we will have'?

From my POV it's already there in many areas.

When I mention something to my son and he's not sure I'd say
"Didn't you learn that in HS physics". [knowing full well that is
one of the must-have course of the past that are often replaced
by mindless electives anymore].

He's gotten a lot better and has complained about 'the engineers'
who have poorly designed things and shipped them, for which he
has to go out in the field to retrofit fixes, that should have
never been required in the first place.

It seems that in many places there are now 'paper engineers' who
have the jobs because of some certificate/degree, but have no
common sense.

Bill

--
Bill Vermillion - bv @ wjv . com

In article <F7CdnR9LisNsr2zeRVn-oQ@giganews.com>,
Ken Maltby <kmaltby@sbcglobal.net> wrote:
And that limited understanding leads to problems.

It's "I don't want/need to know how it works. Just tell me
what buttons I need to push"

When I was doing some database design I endeavored to make all
menus understandable, and readable, and had help for any item on
the menu.

I had two classes of users. Those who never complained, and then
those who called up and said things weren't working.

They NEVER read the screens. They just memorized keystrokes to get
where they wanted to go, and if they ever hit a wrong key they'd
get to a menu - that was well explained and documentes - but since
the screen they were expecting to see didn't appear they'd call for
help.

Those are the 'Just tell me what buttons to push' and when they
push the wrong button there are in deep doodoo.

Bill

--
Bill Vermillion - bv @ wjv . com

In article <2ud2v1di21i2fjllu8pehjbbse03u2c39c@4ax.com>,
Humbug <humbug@tofee.net> wrote:
But recently it has been noted that many students from foreign
countries come to the US for education, and then go back to their
country of origin. They get better pay [in comparison], affordable
medical care, and are treated as part of a company, not just
another body that can be replaced. Parts of the technical
community are starting to treat some employees as if they were part
of the service industry, eminently replaceable.

Bill

--
Bill Vermillion - bv @ wjv . com

Alpha,

?

"Bill Vermillion" <bv@wjv.com> wrote in message news:Iup0D4.1G4v@wjv.com...
Hmm... I don't want you all to get the wrong idea, I deplore
the "Dumbing Down" that has come of our Social Conscious
Education System. For us in the USA, it is going into the third
generation, and the teachers/academics that are defining the
curriculum were themselves a product of the idea that a society
of socially wellrounded citizens, in touch with their feelings,
and holding technology in the disdain they believe it deserves,
is the correct outcome to strive for.

I should think any review of my postings would show that
I have a difficulty dealing with those who refuse to accept
real world results, whether they do so from a lofty perch of
credentialed professionals or the crowd that can't figure out
how to work the shift key.

It is certainly my belief that it is much better to learn the
details and have some real understanding of what you are
doing. I have often expressed my opposition to the "One
Button" approaches that have given us the concept that
you can: "Burn an AVI file to a DVD".

That said; I have come to realize that there are a large,
disturbingly large, group of posters that have no tolerance
for technicalities at all. So, any approach that offers some
hope of reaching that crowd, and is still reasonably accurate
is, to my mind, better than nothing.

Luck;
Ken

On 2/14/2006, Bill Vermillion managed to type:
Very interesting. Helps me understand a lot of experiences I've had.
Thanks for your explanation (or analysis, if you prefer).

Thanks,
Giino

--
Gene E. Bloch (Gino)
letters617blochg3251
(replace the numbers by "at" and "dotcom")