GR Mailbag: Totally Independent Letters
Posted on Tuesday, July 2 @ 12:13:14 Eastern by Duke_Ferris
Subject: NTSC mailbag errors
From: Andrew Shapiro
To whom it may concern,
In your June 19th edition of the mailbag, you responded
to a reader's question regarding the resolution of game
consoles. In your response, the following statement was
"Televisions don't show images the way a computer monitor does.
There are no pixels. The NTSC format (The format used in
America. Other countries use the PAL or SECAM formats.)
actually consists of 525 horizontal lines stacked on top of
each other. The horizontal level of detail depends on both
the TV and the playback device."
In fact this statement is misleading. Television sets do
indeed have pixels. Each part of the color on a screen is
made up of arrangements of Red, Blue, and Green phosphor
patches on the inside of the CRT, and each one of these
groups forms a pixel. However, you are correct in asserting
that televisions do not process video signal the same way a
Computer Monitor does, in that the effective resolution of
a monitor does not translate directly to a television.
There is an effective resolution of a television screen.
That resolution is 720x486, for standard NTSC Video. Of
course on a computer this does not work out to a 4x3 aspect
ratio. The primary reason for this is that Television
screens have non square pixels that are a little bit
taller than they are wide (the exact ratio is 0.9091:1.0)
as opposed to monitors which have, for all intents and
purposes, perfectly square pixels. In that case, one
frequently has to edit graphics or video intended for
broadcast on computer systems at 720x540, which is
conveniently a standard 4x3 monitor resolution.
Unfortunately, the peculiar nature doesn't end there
in that computers produce progressive scan frames which
draw every line on the screen, 60, 72,75, or up to 120
times per second, while Televisions interlace their
images drawing odd lines, and THEN even lines 60 times
per second. So the apparent resolution of television
images is vastly different then those on a computer
Finally, part of the NTSC standard dictates that a
certain amount of screen area is dedicated to, "Overscan,"
This is kind of a safety border around the screen which
should not hold important picture information, and a
smaller area inside it known as action safe which should
not hold text. This area is reserved on Television
because there is no real standard for how much of the
image, a television cuts off and projects either behind
the viewable area of the screen, or outside the phosphor
coated area of the tube. So everyone plays it safe and
leaves the edges blank, reducing the resolution of the
useable television signal further.
This also explains why consoles can get away with
outputting 640x480 video. On the way out, the DAC
converts the signal to analogue composite, or in the
case of S-video, analogue component signals that basically
have 640 vertical lines of useful resolution, and the
rest is filled with black under the assumption that
most of that space will be in this non-viewable overscan
area. If one looks closely at some of the live action
pre-rendered video, this black border will frequently
be noticeable. And two artifacts show why. This video
is frequently jaggy and looks badly compressed. One
reason is that the video was originally rendered from
a 720x480 source such as DV or Mpeg 2, and has been
converted to 640 x 480 using the Mpeg 2 capabilities
of the X-box and the PS2 improperly, the other
possibility is that this video is Mpeg 1, at a
maximum resolution of 358x240.
So while both NTSC, and SVGA Video standards have a
"resolution" as such, SVGA is far superior in terms
of detail and refresh rate, as well as how the signal
is transmitted to the monitor. However, making a
direct comparison by numbers is almost impossible,
and counting horizontal lines of information gives a
much more useful measure of a picture detail in an
Hope that's helpful,
DVD Authoring Engineer
Dear Mr. Shapiro,
Yeah, uh, we were totally
gonna say that, but you know, we were just, like, tired, you know?
Um, can you do our math homework
|All 1337 Up In Da Hizzy.|
From: "Pat C"
Subject: Mail Bag Rant
Am I the only one that is seriously annoyed by all
that "1337" and "ownz j00" BS? I hate that crap with a
passion, and the more I see it, the more it bothers me.
Why can't people just type what they want to say without
having to use some half-assed code language? Huh? HUH?
Why do people feel the need to feel different and special
through the use of symbols and numbers to represent
letters? Are they trying to confuse people like me,
who would rather not be part of that culture? Well,
it isn't working, but it sure is annoying.
Jumpin' Jehosaphat! Look
here old man, don't yell at the kids because YOUR ancient ass can't
keep up. It's just that kind of flimshaw hooey that scares the tarnation
out of them young whippersnappers and makes 'em want to poke yer dern
eye out! Dag nabit! Where's my shoes! Who?
Subject: berkely? john?
since your office is in berkely and theres a
college named calberkley i figured theyre in
the same place and my cousin went to berkely so
maybe you know him cuz hes a computer game dude that
stays up all night playing games and eating cheese doodles
and drinking lots of 7UP. not that thats a bad but his
name is john. do you know him?
Well, we know a lot of Johns.
We used to have a crush on
this John. Look at that hair!
But then this other John got
pissed off because they almost had the same name.
When GR is in trouble, we
call our friend John at the local
police department, who race out to help us and, occasionally, to
disco dance a little.
And who could forget this
John? After all, we have the same name!
|The REAL Reason The Titanic Sunk...|
From: Brad Apel
Subject: the devil and me
I just beat Devil May Cry. Does this make me one with Satan or
No, silly, beating
DMC doesn't make you one with Satan. But if you're interested,
then heed our advice and do it the easy way by buying a ticket to see
her in concert.
|Judge, One Restraining Order, Please.|
Date: Wed, 19 Jun 2002 00:35:40 EDT
Subject: Knock Knock
Hey guys, I have been going to your site for quite some
time but never really found the time to write to you.
Anyways I read the mailbags and everything and at
the bottom I saw an address:
740 Gilman St.
Berkeley, CA 94710
I said, 'Hey where's that?' So I took a little road
trip down to Berkeley and it took a little while to
find. But I did find it and I went to the bathroom
on the front floor. Then I went up these beat up
looking stairs and took a left. While coming upon
it I realized the Monsters Inc. door mat. Sweet I
said to my self and I knocked on the door. Wow, I
might be able to see the people who work in GR and
what would I say, what would I do? But to my avail
no one answered my knocking. But then some guy from
the room saw me and I asked 'Do you know if there's
anybody in GR right now?' He knocked and like
before no one answered. I ended up leaving with
my heart shattered unable to see the people who
work in GR. Where were you guys?
Dear Unfortunate AOL STALKER,
Man, we are so bummed we
missed you. Actually, we decided to visit YOU at YOUR house that very
same day! Yeah! We showed up at your front door totally unannounced
carrying little knives, because, after all, you never know what kinds
of NUTS are out there, eh? So yeah, we climbed in your window and hid
in your closet for a few hours, stroking our knives, just waiting for
you to get home so we could surprise you with big hugs! We even scrawled
a message in blood on your mirror saying that we were sorry we missed
you, but that we would return at a later date, probably late at night.