Maker Pro
Maker Pro

Fields per second vs. Frames per second

G

Gene E. Bloch

Jan 1, 1970
0
Hmm, yes, I can see now how there are other possible ways to interpret it.
But, my name was mentioned in the quoted segment just above that comment, and
the comment seemed to be in some sort of disagreement with what I had said.
Or what you said I had said, and seemed to agree with, if you know what I
mean. (This is the sort of confusion we get when people quote entire messages
without trimming their quotes to the point.)


Perhaps he meant himself. There are certain archetypical categories of people
who are said to refer to themselves in third person, and self-hate is not a
too uncommon disorder. It could be taken as some sort of self-irony as well.
:)

Yeah! That's it!

Thanks, Jukka (is that your given name or family name? I know that some
Ugrics put their family name first, but I don't know about the Finno
branch... :) ).
 
G

Gene E. Bloch

Jan 1, 1970
0
It wasn't amied at you, but the person you replied to. (grice) He is
kill filed under 18 aliases, and keeps adding new ones.

On the other hand, it was in a reply to *my* post, not Grise's, and
right below a comment of mine. Also, it was not particularly in any
context of those posts.

As I said, it was the nicest thing anyone had said to so far in the day
:)
 
J

Jukka Aho

Jan 1, 1970
0
Gene said:
Thanks, Jukka (is that your given name or family name? I know that
some Ugrics put their family name first, but I don't know about the
Finno branch... :) ).

"Jukka" is my given name. Finns usually prefer marking their last name
last, where possible. Common exceptions to this rule are alphabetized
catalogs (such as phone books) or official forms and certificates (such
as a driver's license, or the form you would fill when applying for
one.) Those would typically place the last name before the given
name(s).

I have a second and a third given name as well, but I don't usually use
the full form of my name, except if required by authorities or some
other sort of bureaucrats. Those two other names really only live on
paper and in official registers. I've sometimes considered taking the
initials in use but have not yet found any sufficiently compelling
reason for that. There just haven't been too many incidents where I
would have been mistaken for someone else by the same name - even though
there _are_ people by the same name.

* * *

The etymology of the name "Jukka" is discussed here (this is one of
those "more information than you could possibly want" pages, but there's
a brief "executive summary" at the beginning):

<http://www.cs.tut.fi/~jkorpela/jukka.html>

My last name ("Aho") means "a clearing in the forest; an open field".
Not particularly poetical, is it? The meaning is all but forgotten now,
though, and the word is not really actively used in that sense any
longer. I don't think too many among the younger generation (or among my
own generation, either) are even aware that it _has_ a meaning. For them
it's "just a surname".
 
B

Bob Myers

Jan 1, 1970
0
Bob, since the video camera scans both fields from the same frame of
film, there is no "Difference in Time".

I realize now that it may not have been clear that I'd switched
contexts in the above, from film-originated material to interlacing
in general (and more specifically, the sort which originates AS
"video", i.e., what comes out of a standard TV camera.
As far as slight differences, the persistence of the human eye tends
to average out the minor differences.

Yes, but that's exactly where the "motion problem" in
interlaced material (again, that which originates that way,
from a camera) comes into play. You DO average out
successive fields, but since they're being presented in an
interlaced manner (at least in a properly-adjusted receiver
or monitor), the effect is a blurring of details. This is one
of the reasons that an interlaced system doesn't actually
deliver the resolution one would assume from the scan
format. For instance, the 525/60 scanning standard (as
used in North America) provides a bit over 480 "active"
lines per frame, but delivers only about 340 lines' worth
of effective vertical resolution. (Another way this is often
expressed is to say that the standard assumes a "Kell
factor" of 0.7; 0.7 times 484 lines is 338.8 lines.)
Another contributing factor to this effect, at least for CRT-
based displays (which is all there was, of course, when the
standard was written) is that a CRT running interlaced
can't be focused to the point where the individual lines are
fully resolved (to do so would result in horrible line
"twitter" owing to the 30 Hz refresh rate for any single
line).
You may not like the "Frame" concept, but I find "Progressive Scan"
to be stupid. Progressive? they went back to the earliest video scan
method, and have the nerve to call it "Progressive"?

Well, "progressive" of course doesn't refer to it being a
more advanced method. It IS, if you have the bandwidth, a
better way to scan. Interlaced scanning really was adopted
in the first place only because it's a crude-but-effective form
of analog "compression," permitting a higher image resolution
than otherwise would be the case in the available bandwidth.
It surely doesn't benefit the system in any other way (it is harmful
in terms of image quality, somewhat) and you wouldn't go to all
the trouble involved in an interlaced system (the half-lines at the
end of the fields, the "equalization" pulses, the need to adjust the
relative field positions at the display end, etc., etc., etc.).

Bob M.
 
B

Bob Myers

Jan 1, 1970
0
Jukka Aho said:
[1] "Progressive scan" is becoming more and more of a misnomer in itself.
These days, usually neither the camera producing the images - and,
increasingly, not even the display device - "scans" any longer.

Good point; a lot of things in TV standards, though, make sense only
if you adopt a mid-1960s (or even earlier!) mindset when looking
at them! :)

Bob M.
 
J

Jukka Aho

Jan 1, 1970
0
Bob said:
Interlaced scanning really was adopted in the first place only because
it's a crude-but-effective form of analog "compression," permitting a
higher image resolution
than otherwise would be the case in the available bandwidth.

The origins of interlaced scanning (as a patented invention) and the
contemporary reasoning behind adopting that scheme were discussed some
time ago in another thread. Most of s.e.b readers probably missed that
thread because it was not crossposted there. Here's a link to that
discussion: (You may need to manually copy and paste the two-line URL
together.)

<http://google.com/groups?threadm=PxiPg.14203$NS2.6927@rea
der1.news.jippii.net>

The message linked above contains an excerpt from Randall C. Ballard's
1932 patent, and provides a link to the full patent text. (Note that
Ballard's tv system - the one described in the patent - has a different
field rate and a much coarser resolution than modern tv systems.)
It surely doesn't benefit the system in any other way

There are two other benefits:

1) When compared to a progressive scan system that has the same
bandwidth and (nominally) the same spatial resolution for full screen
images, interlaced scanning provides twice the temporal resolution (that
is, motion updates per second.)

The price to be paid for this is that objects in motion will only
receive half the (perceived) vertical resolution when compared to
objects that stay still. It can be argued whether this difference is
noticeable enough that anyone should care. Some people say it is, some
others think it isn't. In any case, motion will appear very smooth and
fluid with 50 Hz or ~60 Hz updates, which is great for e.g. sports, and
allows for fast, smooth pans and zooms without making the picture
incomprehensible flickery jumble. (Those who have ever shot Super8 film
know how careful and slow one must be with zooms and pans when dealing
with a medium that has a low temporal resolution.)

2) Scanning through the whole CRT screen twice as many times per second
will dramatically reduce perceived flicker. (Again, when compared to a
corresponding progressive scan system that has the same bandwidth and
[nominally] the same spatial resolution.)

This benefit comes with a price as well: it will introduce some annoying
twitter in thin, contrasty horizontal lines. Line twitter can be reduced
quite nicely by employing modern image processing algorithms, though.
(There are video encoder chips that do this kind of parameter-based
intelligent, adaptive, dynamic vertical filtering in real time.)
 
S

Smarty

Jan 1, 1970
0
Jukka,

Having traveled as an English-speaking American in Helsinki and elsewhere in
Finland, I have to add that the majority of Finnish words including names
and proper nouns is among the most daunting languages I have encountered, in
some respects exceeding Japanese and Chinese which I also find totally
intimidating. On the bright side, the many Finns I have met are truly
wonderful and kind, and your Lakka cloudberry liquor is heavenly, and among
my absolute favorites, despite the fact that is nearly impossible to find in
the U.S.

Smarty
 
J

jasen

Jan 1, 1970
0
:

As usual, the greaseball is wrong. A TV projector in a film chain has
a special shutter that runs the 24 FPS film to match the 30 FPS video
rate by showing every 4th frame twice:

He was talking cinema not tv. cinema projectors have the shutter close
several times per frame.

also where TV is 25 frames per second they run the film at 25FPS, and
have more time for advertising.
 
J

Jukka Aho

Jan 1, 1970
0
Smarty said:
Jukka,

Having traveled as an English-speaking American in Helsinki and
elsewhere in Finland, I have to add that the majority of Finnish
words including names and proper nouns is among the most daunting
languages I have encountered, in some respects exceeding Japanese and
Chinese which I also find totally intimidating.

That's to be expected when you're dealing with a language that belongs
to a completely different language family. Speakers of major
Indo-European languages get it easy: they share much of similar
grammatical structures and vocabulary among each other. It should be
relatively straightforward to pick up, say, Dutch if you already speak
English, and German once you know Dutch. Or if you know Spanish or
French, Portuguese or Italian newspaper stories might already appear
nearly readable. But when you switch from one major language family to
the other, all bets are off: nothing you previously knew about sentence
structures and vocabulary is any longer relevant, or in any way useful.
:(
On the bright side, the many Finns I have met are truly wonderful
and kind, and your Lakka cloudberry liquor is heavenly, and among my
absolute favorites, despite the fact that is nearly impossible to find
in the U.S.

To commemorate that liquor, the obverse side of Finnish 2 euro coins is
minted with a depiction of a cloudberry plant. [1] Or was it the liquor
that commemorates the coin? One can never know these things for sure.

(Just pulling your leg. :) I'd better Finnish now before I tell more
lies!)

_____

[1] <http://en.wikipedia.org/wiki/Finnish_euro_coins>
 
M

Martin Heffels

Jan 1, 1970
0
Having traveled as an English-speaking American in Helsinki

Yeah, Finland is nice, except for the mosquitos ;-)

-m-
--
 
D

Dave Martindale

Jan 1, 1970
0
Rich Grise said:
You might be interested to know that 24FPS movie projectors actually
project each frame twice, so you get an effective flicker rate of 48
FPS.

Or three times each, giving a flicker rate of 72 Hz. This is better for
smaller theatres, where the screen brightness tends to be higher, since
the eye's flicker fusion frequency is higher in frequency at higher
brightness.

On the other hand, it wastes light (since each of the dark periods needs
to be the same length, and each dark period needs to be as long as the
pulldown time, having 3 dark periods per 1/24 second always wastes more
light than two) so there's no point doing it when screen brightness is
already low with a two-flash shutter.

Dave
 
M

Michael A. Terrell

Jan 1, 1970
0
jasen said:
He was talking cinema not tv. cinema projectors have the shutter close
several times per frame.

also where TV is 25 frames per second they run the film at 25FPS, and
have more time for advertising.


Then the audio frequencies would be off by about 4%.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
M

Michael A. Terrell

Jan 1, 1970
0
Gene E. Bloch said:
On the other hand, it was in a reply to *my* post, not Grise's, and
right below a comment of mine. Also, it was not particularly in any
context of those posts.

As I said, it was the nicest thing anyone had said to so far in the day
:)


WHat kind of day WAS it? ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
S

Smarty

Jan 1, 1970
0
Thanks Jukka for your comments. The Slavic influence on your language is
apparently one of the reasons Americans like myself are daunted.

I was unaware of the coin image of the cloudberry, but can understand why it
is so exalted. Maybe the U.S. dollar will someday get a Budweiser beer
emblem...

Smarty


Jukka Aho said:
Smarty said:
Jukka,

Having traveled as an English-speaking American in Helsinki and
elsewhere in Finland, I have to add that the majority of Finnish
words including names and proper nouns is among the most daunting
languages I have encountered, in some respects exceeding Japanese and
Chinese which I also find totally intimidating.

That's to be expected when you're dealing with a language that belongs to
a completely different language family. Speakers of major Indo-European
languages get it easy: they share much of similar grammatical structures
and vocabulary among each other. It should be relatively straightforward
to pick up, say, Dutch if you already speak English, and German once you
know Dutch. Or if you know Spanish or French, Portuguese or Italian
newspaper stories might already appear nearly readable. But when you
switch from one major language family to the other, all bets are off:
nothing you previously knew about sentence structures and vocabulary is
any longer relevant, or in any way useful. :(
On the bright side, the many Finns I have met are truly wonderful
and kind, and your Lakka cloudberry liquor is heavenly, and among my
absolute favorites, despite the fact that is nearly impossible to find in
the U.S.

To commemorate that liquor, the obverse side of Finnish 2 euro coins is
minted with a depiction of a cloudberry plant. [1] Or was it the liquor
that commemorates the coin? One can never know these things for sure.

(Just pulling your leg. :) I'd better Finnish now before I tell more
lies!)

_____

[1] <http://en.wikipedia.org/wiki/Finnish_euro_coins>
 
S

Smarty

Jan 1, 1970
0
Never encountered them. In Lapland and the Arctic Circle portion of Finland,
they are not as likely an issue, but Jukka may know for sure...

Smarty
 
B

Bob Myers

Jan 1, 1970
0
Michael A. Terrell said:
Then the audio frequencies would be off by about 4%.

Yes, they are - but it still often IS done that way, and they
simply live with the errors that result.

Bob M.
 
J

Jukka Aho

Jan 1, 1970
0
Smarty said:
Thanks Jukka for your comments. The Slavic influence on your language
is apparently one of the reasons Americans like myself are daunted.

There's Baltic, Germanic, and Slavic influence in the vocabulary, but
I'm not sure how significant the Slavic influence alone has been when
compared to the others. Wikipedia has something on the subject:

<http://en.wikipedia.org/wiki/Finnish_language#Borrowing>

I'd imagine the Swedish influence is probably the strongest - at least
among the relatively recent loans - since Swedish has been the
admistrative language for most of the written history of the country.
Loan words will usually assimilate fast, though, becoming more
"Finnishized" in the process in both their pronunciation and spelling,
so the origins of a given word may not always be too obvious.

Moreover, for the last 150 years (or so), there has also been an
on-going conscious effort of producing new "truly Finnish" words for new
concepts instead of just importing words from other languages. (Compare
to the French language and the French Academy.) This doesn't always work
out as intended, but many concepts and gadgets that were originally
called by their foreign names when they were first introduced now have
firmly rooted Finnish names because of this policy (i.e. the original
loan word has fallen into disuse and oblivion.)

Geography will also play part, of course. For example, the dialects
spoken near the Eastern border have some Russian influence in their
vocabulary - this can be witnessed most easily in the religious
vocabulary of those Karelians who subscribe to the Eastern Orthodox
faith - whereas the dialects spoken on or near the West coast (such as
in Ostrobothnia, where I come from) borrow many words from Swedish.

TV - the great equalizer - has made those differences much less
pronounced, though. When not among their "own people", most people will
speak Finnish in a fairly neutral or "standard" way, without necessarily
giving away the part of the country where they're from.
I was unaware of the coin image of the cloudberry, but can understand
why it is so exalted. Maybe the U.S. dollar will someday get a
Budweiser beer emblem...

Heh. That's a coin I'd like to see! :)
 
J

Jukka Aho

Jan 1, 1970
0
Never encountered them. In Lapland and the Arctic Circle portion of
Finland, they are not as likely an issue, but Jukka may know for
sure...

Actually - as strange as it might seem - Lapland is kind of notorious
for its mosquitos. They're fierce and plentiful in there, but will only
reign during the summertime, of course! There's more about them on these
pages:

<http://www.virtualtourist.com/travel/Europe/Finland/Lap
pi/Ivalo-240898/Warnings_or_Dangers-Ivalo-BR-1.html>

<http://www.ebnitalia.it/trips/trip08.htm>

<http://wikitravel.org/en/Finland#Stay_healthy>

Mosquitos can be found all over the country during the summer -
especially near swamps, streams, and lakes, since they need a bit of
water in order to reproduce - but the ones in Lapland usually seem to
get particularly bad rap. I have never been to Lapland during the
mosquito season myself so I can't really say whether this notoriety is
justified or not.
 
J

Jukka Aho

Jan 1, 1970
0
Yes, they are - but it still often IS done that way, and they
simply live with the errors that result.

....or time-compress the sound track without changing the pitch. (The
wonders of modern technology, and all that.)
 
H

Homer J Simpson

Jan 1, 1970
0
Mosquitos can be found all over the country during the summer - especially
near swamps, streams, and lakes, since they need a bit of water in order
to reproduce - but the ones in Lapland usually seem to get particularly
bad rap. I have never been to Lapland during the mosquito season myself so
I can't really say whether this notoriety is justified or not.

Sounds like the north woods of Canada!
 
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