DVD-Widescreen question

I own several DVDs All of them are widescreen, some are even wider than 16:9 (e.g. Lord of the Rings with a ratio of 2.35:1).

According to Wikipedia, DVD-video can hold 720x480 pixels (in the US), which is an odd ratio (3:2) considering most televisions are either 4:3 or 16:9. That is another question, but I’m trying to keep this simple.

When I watch Lord of the Rings, I assume they have to take the ratio of 2:35:1 and smash it into a 3:2 ratio because that is what DVD-video holds. Now, that involves adding black bars on the top and bottom.

Are those black bars taking up information on the DVD? I assume that a large portion of the DVD is encoded with nothing but black, while a slice down the middle of the frame actually has real information with a resolution of 720x306.

Is this true? So wider formats actually end up with worse resolutions because you have to fit them in a 720x480 box?

Nope. If it’s an anamorphic widescreen DVD (like Lord of the Rings), it means squeezing the wide picture horizontally so it fits in the standard DVD signal.

If it’s an anamorphic widescreen DVD, no part of the image is being wasted with black. If it’s a letterboxed DVD (super lame) then the black bars are indeed part of the DVD image. You don’t see too many letterboxed DVDs anymore, thankfully.

For letterboxed, yes, for anamorphic, no. With anamorphic widescreen, assuming your TV is set up correctly, the black bars are added by the TV to make the image fit correctly, and are not part of the signal.
ETA: Excellent article which demonstrates the difference using framegrabs.


Looking at your link, every widescreen DVD I have looks like the one in the bottom left on my widescreen TV.

The DVD starts in its DVD “menu” as if it were on a regular sized TV (square, with vertical black bars on the sides). Once the movie starts, the vertical black bars on the side remain, but we now have added black bars on the top and bottom (a slightly different shade of black than the vertical bars). I have to use my TV’s “picture size” modes to make it fill the screen.

This is how pretty much every DVD that I get from Netflix operates. This would mean they are all non-anamorphic?

It’s more likely that you’ve a setting wrong on your TV or DVD player, probably DVD player. Consult the manual for the setting to tell it you have a 16:9 TV.

You’re using composite cables (red/white/yellow) to connect your DVD player, right?

From that link, the anamorphic example is 16x9 (1.85x1) squished into 4x3, but the OP was asking about 2.35x1 DVDs. For those, even the top right picture would have black bars top and bottom. Do those bars take data, or is all the data usable in the actual picture region?

ETA: as in this link.

Yes, 2.35x1 is too wide even for anamorphic widescreen, so there are letterboxing bars in the DVD signal for that.

A big second for this. Hermitian, you need to change a setting in your DVD player. There should be a button on the remote for “Setup” or “Settings”, which will take you to the DVD player’s internal settings menu. From there, look for a setting called something like “TV Type”. There will probably be three settings: “4:3 Normal”, “4:3 Letterbox”, and “16:9”. Change it to the “16:9” setting. While you’re in there, you may also want to look for another setting with options for “Interlaced” and “Progressive”; change it to “Progressive” for another step up in picture quality.

Oh, and seconding the last bit, too: connect via composite video cables for the best possible picture. That’s the red-green-blue connectors, probably labeled “Y-Pb-Pr”. Or, if you have HDMI connectors on your DVD player and TV, that’s an even better option, and much easier cabling. The “progressive” option needs one or the other to work properly.

I’m sort of chuckling to myself about this, because I have a mental picture of you seeing a DVD like Lord of the Rings in full anamorphic glory for the first time and being blown away. It really will make a huge difference over a zoomed picture, especially if you have a large TV.

Not an expert, but I recall reading that the compression on DVD adapts to the picture. You have a fixed bit-rate per second, and obviously solid black uses some but very little of that data. OTOH, this means better quality in terms of sharpness and depth, less artifacts, but will not exceed the basic resolution of the DVD output - 720x480. The 480 is teh number of horizontal lines in a regular TV signal (minus the retrace)

What’s confusing about DVD and 720x480 is there is no law saying pixels must be square. In a normal 4:3 picture, the pixel output from a DVD will be slightly sharper horizontally than vertically - whereas you typical digital camera uses nice square pixels, and will make a video the same screen ratio at 640x480.

In addition to the above advice try the AVS Forums. Anything you want to know about home theatre is there. :slight_smile:

I’ll have to look at my DVD-Player settings when I get home. That setting does sound familiar and I probably have it set up for my old TV.

Thanks for the help.

You mean “component”, don’t you? A whole lot better than “composite” (which would have red, white and yellow connectors, as I recall). I’m sure this was just a typing error.

You could actually use a composite cable set on your component connections, as long as you were careful in your end-to-end color substitution, of course. Both cables are just conductors, and the ends are color coded for convenience. So if you have composite terminals on both electronic components but don’t happen to have a “component” cable set, you can just let red = red, blue = white and green = yellow (or whatever) and re-use the “composite” cable set you have already.

Dangit, I always get those terms mentally crossed. What CannyDan said.