DivxGuy

Against my better judgment, I put together an explanation of the challenges for 16x9 owners in using 1.66:1 4:3 letterbox.

I'd be interested in opinions, if anyone is willing to venture such.

Mods, if this is not permissible, I apologize (I made a point of ensuring that the page has no links to any other URLs, and contains nothing other than the subject matter).

Thanks, RD

djtoell

You claim that the first two screenshots are displayed in the proportions stored on the disc. You're incorrect. The raw image on DVD is 720x480, making for an AR of 1.5:1. Both of your screenshots, however, are 400x300, for an AR of 1.33:1. You're unnecessarily over-distorting the 16x9-enhanced screenshot and un-distorting the non-enhanced screenshot. Both shots should be displayed at 1.5:1 if your goal is to show the proportions at which they are stored on the disc.

DJ

DivxGuy

Thank you for pointing that out; the 4:3 captures are what PowerDVD returned (WinDVD returns properly proportioned ones). None of the tutorials I've come across have let this piece of technical trivia be known; considering all the bitter complaints from 4:3 owners concerning downconversion artifacts, you'd think the pro-16x9 camp could benefit from letting these people know that their images are being scaled regardless.

Now I have to change all those painstakingly created images. Aargh!

Thanks again!

RD

Josh Z

Posting an accurate screen cap is more difficult than you'd assume, because DVD pixels are not square.

DivxGuy

Sounds like the old CGA and EGA monitors, where the pixels were rectangular rather than square. Does that mean that the raw DVD images is 4:3 on NTSC monitors, or does the image require some horizontal compression?

For anyone who's interested, I added a considerable amount of material to the writeup.

RD

djtoell

To get a raw DVD image to appear correctly on 4x3 NTSC monitors, the image gets compressed horizontally to bring the AR from the native 1.5:1 (assuming pixels are somehow natively square) to 1.33:1. On 16x9 monitors, the image is stretched horizontally to get from 1.5:1 to 1.78:1. Either way, non-square pixels are used.

DJ

DivxGuy

I sold my RP-91 to relatives, which left me with only the HTPC as a source of progressive scan material.

To make a long story short, I am using the TheaterTek software DVD player now, with the HTPC's Radeon video card operating in a custom 856x480 mode. It appears that when this is done, the HD set displays the image without any further "stretching," and setting up a custom aspect ratio allows use of the entire raw non-enhanced 1.66:1 image. The results are less than stellar so far, because all of my non-enhanced 1.66:1 discs have old transfers of modest quality.

Of more interest here is the limitations of all too many transfers really show up in this mode. For example, in contrast to Ghost Ship (go figure!), That Thing You Do comes across as mediocre, with low levels of detail and flaws like occasional edge enhancement halos. This is in spite of the fact that it is 16x9-enhanced and only two years old.

One conclusion that seems to be in order here is that if a transfer hasn't been optimized for larger displays, anamorphic enhancement isn't going to make much of a difference.

RD