"Things..." episode 010.

010: More fun with pixels.

You're obviously familiar with television, known these days as "standard-definition television" (SDTV). And you've probably at least heard of high-definition television, or HDTV. But what about enhanced-definition television (EDTV)?

The EDTV format lies between SDTV and HDTV, quality-wise. Though it is seldom referred to as such, the common DVD player is actually an EDTV device. While a DVD player can generate a signal for a standard-def television set, it can also generate a higher-quality signal for a widescreen high-def set.

The actual resolution of this enhanced-def image is the same as the standard-def image I wrote about last week: 720 x 480. But, where the SDTV pixels are interpreted as "skinny," the EDTV pixels are interpreted as "wide." Instead of the boring old 1.33:1 aspect ratio, an EDTV image is displayed in the glorious widescreen aspect ratio of 1.78:1 (16:9, to be exact).

So, what happens when you play these wide pixels on a standard-def television, with its skinny pixels? The DVD player is smart enough to decode this image on the fly and output a "letterboxed" SDTV image, with black bars at the top and bottom of the screen to keep the image at the correct aspect ratio.

Here are a few examples, featuring Mr. Kyle Holman in a shot from Interplanetary...

EDTV image as encoded, 720 x 480 pixels.



EDTV image as displayed on a widescreen television, 854 x 480 pixels.



EDTV image as displayed on a standard television, 640 x 480 pixels.



Since television resolution is all about the "lines" (vertical resolution), the EDTV scheme is pretty clever. It is a way to display a widescreen image and still use all the available vertical pixels. With standard letterboxing, a significant number of lines are basically wasted, displaying only black bars.

I mention all this because many video cameras can record EDTV images. And, if you're shooting film (yay!) and composing for widescreen, you can have it transferred to video in an EDTV format. An ED transfer isn't as sharp as HD, but it is usually a lot cheaper. And, of course, better than letterboxed SD.

I think two posts about pixels are enough for the time being -- I'll move on to something less esoteric next week. But, if you have any pixel questions, email them to me or write them up in a blog comment, and I'll answer them in a future post.

Now playing.

Chuck and I caught a matinee of Mulberry Street on Saturday. It's kind of like 28 Days Later relocated to Manhattan with rat-zombie-monster-things. I think the theatrical run was just for this weekend, but Mulberry is worth tracking down when it arrives on DVD.

EDIT: Just realized the After Dark film series, of which Mulberry Street is a part, is playing through Thursday. Check your local listings for details.

People take Dwight Yoakam for granted. He's been consistently good for such a long time, his new releases seem to be met with an attitude of, "Oh, another Yoakam album, I'm sure it's great, whatever." I'm guilty of this, too, but I'm happy to report 2005's Blame the Vain (I finally got around to listening to it last week) is, indeed, another great Yoakam album.

"Other Worlds Than These" episode 009.

009: Monsters HD.

As far as I can tell, Monsters HD is only available on Dish Network. Which is a shame, because this is a channel everyone needs. As you might guess from the name, Monsters HD shows horror flicks and creature features 24/7 in beautiful high definition (uncut!) (and often in their original aspect ratio).

I caught Halloween III on the channel recently. And they're showing Carpenter's original The Fog tonight! Their programming runs the gamut from the classic to the enjoyably terrible. If you're a genre movie fan, you should really consider getting a Dish system, just for this channel. Or maybe you could make friends with a Dish subscriber...

Notes for Thursday.

1. Been up late the last couple of nights working on a teaser trailer for Interplanetary -- it should be ready and viewable online next week.


2. I haven't forgotten about today's installment of "Other Worlds Than These." I'll hopefully get it written and posted tonight or early tomorrow.


3. Stacey, my better-half and producer, will be exhibiting some of her photography tonight at Rojo, a groovy bar and grill here in Birmingham, Alabama. Interplanetary friends Ted Speaker, Arik Sokol, Tony Diliberto, and Natalie Hummel will be showing off their shots, too. Check out Rojo's MySpace page for more info.

"Things..." episode 009.

009: NTSC primer no. 1 (all pixels are not created equal).

Carol recently emailed me with a video resolution question, so I thought it might be a good time to discuss that topic on the blog. The analog signal standard for North American televisions, and many North American video cameras, is NTSC. An NTSC image has a resolution of 720 pixels wide by 480 pixels high* and an aspect ratio of 1.33:1**.

Divide 720 by 480 and you get 1.5. Given that pixel count, how can an NTSC image have an aspect ratio of 1.33:1?

The pixels aren't square.

"Skinny" NTSC pixels displayed as square pixels -- notice how the image looks a bit wide?



The same image, properly displayed as 640 x 480 square pixels.



(Click either of the examples*** for the full-resolution version.)

As a reasonable human being, I find it absurd that somebody created a broadcast standard based on pixels that are not square -- it is an unnecessary complication. But NTSC is littered with plenty of other bad decisions, some of which I'll discuss in later posts.

So, anyway, what do these non-square pixels mean to you? If you're working on a project that starts in NTSC and stays in NTSC (through delivery on DVD, for example), there's not much to worry about. Software editing systems (like Final Cut Pro) compensate for the screwy NTSC pixels, so your images look fine on the computer monitor (which, sensibly, has square pixels).

If, however, you're exporting NTSC video to another format (like a QuickTime video for the web), you'll need to change the video resolution on output to something with the proper 1.33:1 aspect ratio. For a "full resolution" video, you'd output to 640 by 480 pixels. I guess that's technically only full vertical resolution. But, in the video world, for some reason, it's all about the vertical resolution (often referred to as "lines"). So, it's best to keep your image 480 pixels tall and adjust the horizontal pixels as appropriate. You can make smaller video for computers at 480 x 360 pixels, 320 x 240 pixels, etc.

I think that's enough math for today -- more NTSC madness next week.

*A "full" NTSC image (available, for example, from a DigiBeta tape) is actually 720 by 486 pixels. Most modern NTSC video mediums (including MiniDV and DVD) throw out six vertical pixels for the sake of simpler mathematics.

**This 1.33:1 aspect ratio applies to a classic "standard definition" image. An "enhanced definition" image has an aspect ratio of 1.78:1 -- more on that topic at a later date.

***That sexy guy in the space suit is Chuck, by the way.

Preparing for half a weekend.

Outside the mini storage, piling up props against the ol' Honda Element...




We had to change our scheduled shoot from two days to one day due to a conflict at the location. On the bright side, I have more time to prep for shooting on Sunday.

And blogging.

"Other Worlds Than These" episode 008.

008: Scary every day.

As someone who dabbles in the making of horror movies, I like to watch horror movies, both for fun and to see what other filmmakers in the field are up to. But, as there are so many horror flicks out there (with more coming every week), it's hard to keep up.

BC to the rescue. He watches a horror movie every day and reviews it on his blog, appropriately titled "Horror Movie a Day." By my count, he's already written 300 or so reviews, covering everything from the classics (like The Texas Chain Saw Massacre) to the crap (like Dark Ride).

There are plenty of horror movie web sites, but I don't know of another one strictly dedicated to quality (and quantity!) horror film criticism. If BC keeps it up, he may well become the Roger Ebert of horror.