Why not encode to an anamorphic resolution?

[NearlyCritical]

Many recent 4:3 TVs have a widescreen mode. This mode basically uses all the vertical resultion in an anamorphic DVD to increase the picture quality when displayed in widescreen.

Take for example a 2.35 anamorphic PAL DVD. The resolution is 720x576 and when displayed in standard 4:3 mode the DVD player will reduce the vertical lines from 576 to 306 and add borders top and bottom to maintain aspect ratio. If the TV has widescreen mode then the DVD player outputs the full 576 lines and the TV will add borders top and bottom, but the actual picture will still be 576 lines therefore increasing picture quality.

Now, when encoding a DVD to DivX for example we convert from anamorphic resolution to a 4:3 resultion 720x306 then reduce that to 640x272. This keeps the aspect ratio correct (2.35:1).

I haven't tested yet, but why not keep the anamorphic resolution 720x576 then reduce this to 640x512 (less bitrate needed). Ofcourse, this will be out of aspect ratio on any 4:3 display (monitor and TV), but when output to a TV with widescreen mode then picture quality should be noticeably better.

Thoughts and suggestion welcome ....

[BxWrapper]

Go for it if you do not object on 2-3 CD ripping.

Some people feel lucky when they got 2.35:1 AR movie because they can rip it to a single CD with good quality.

[NearlyCritical]

Originally posted by BxWrapper
Go for it if you do not object on 2-3 CD ripping.

Some people feel lucky when they got 2.35:1 AR movie because they can rip it to a single CD with good quality.


I usually do 2 cd rips, so that should be no problem :) One question, you say some people feel lucky when they get an anamorphic movie, all of my widescreen movies are anamorphic (30+ DVDs) ... is this different where you are?

[BxWrapper]

I maintain AR when do encoding and get rid of the anamorphic effect. So I will resize to something like 640x272 and this will fit nicely for 1 CD rip for 2 hours movie (with ogg).

It always challenging for me if the movie 1.85:1 or worst 1.33:1 since I usually have to go 2 CDs for acceptable quality.

[NearlyCritical]

I guess it comes down to quality vs size. I am happy to use additional CDs to get DD5.1 sound and anamporphic quality. I figure I am doing these rips to last me 5-10 years or longer and during this time I am likely to own either a very large HDD (maybe 500GB to 1TB) or better and cheaper media (DVD media). Then I will be able to put all my movies on the one hdd or several movies on one disc.

The other consideration is that TVs are improving dramatically during this time and I it will be much more important to have high quality source material.

[DJ Bobo]

4:3 TVs with widescreen mode *DON'T* increase vertical resolution *AT ALL*. They do what your DVD player does: they resize the picture down to 720x406 (and not 306) and add once again black bars.

So anamorphic encoding is only good if you have a real 16:9 TV.

BTW, there is no 2,35:1 encoded DVDs. There is only 4:3 or 16:9. 2,35:1 movies are encoded in 16:9 mode with black bars.

[manono]

Hi DJ Bobo-

I hate to argue with you on this one, because you're usually right, and I could easily wind up on the wrong side. So, maybe you can elaborate a bit more.
4:3 TVs with widescreen mode *DON'T* increase vertical resolution *AT ALL*.

Yes-NearlyCritical was plainly wrong on this one. The actual picture is not 576 lines with black bars added above and below. A PAL TV has only a total of 576 lines to begin with. He may not have been clear in his explanation, because I think he has some good suggestions. But he'll get a better picture anyway when encoding at 640x512 as he suggested and using the widescreen mode on his television. Less vertical information will have been lost when compared to encoding at 640x272 (I think). I realize I'm not taking filesize or average quant into account here. We don't disagree there, do we? OK, here's the part where I think I disagree:

they resize the picture down to 720x406 (and not 306) and add once again black bars.

720x406 is 1.77:1 or 16:9. But by the time it reaches the TV, it's no longer DAR, but the movie AR, which for a 2.35:1 movie will be 720x306 or thereabouts (as NearlyCritical said). It's been resized by the DVD player. If it were really 720x406, you'd have some really skinny people. But maybe I misunderstood something. And maybe you can teach me something.

2,35:1 movies are encoded in 16:9 mode with black bars.

Where you are, maybe. There are still, unfortunately, way too many widescreen letterboxed 4:3 DVDs available. This is perhaps more true in NTSC countries. I understand that almost all of the European widescreen movies are anamorphic. But that's definitely not true in America. And an Anamorphic DVD will make a better quality DivX conversion than will a letterboxed widescreen 4:3 DVD, and will display a better picture on a monitor or standard TV set. And, of course, an Anamorphic DVD will give you a way better picture on a widescreen TV than will a letterboxed widescreen 4:3 DVD.

[NearlyCritical]

I hate to disagree ... but widescreen mode on 4:3 TVs uses all the lines available in an anamorphic DVD. This is the whole point of 16:9 mode on 4:3 TVs.

Instead of the DVD player letterboxing and sending a 4:3 picture to the TV ... the TV takes the full anamorphic resolution and displays it as a widescreen picture, substantially improving quality.

http://www.sony.com.hk/Electronics/cool/drc/vcom_tec.htm

This shows for example that all the resolution is focused on the screen. You can switch the image bewteen 4:3 mode and 16:9 compression mode to see the difference.

[Stampede]

I found this explanation far easier to understand:

Anamorphic vs. Non-Anamorphic DVD (1.85:1 Aspect Ratio Film)
http://www.thedigitalbits.com/articles/anamorphic/anamorphic185demo.html

Anamorphic vs. Non-Anamorphic DVD (2.35:1 Aspect Ratio Film)
http://www.thedigitalbits.com/articles/anamorphic/anamorphic235demo.html

And if you're really into it you can read the whole guide here:
Page 1, http://www.thedigitalbits.com/articles/anamorphic
Page 2, http://www.thedigitalbits.com/articles/anamorphic/page2.html

DJ Bobo said everything the way I always understood it before.

[DJ Bobo]

@ manono
I havn't mean the actual movie resolution, but the resolution of the whole picture stored on the DVD. So the DVD player takes the 720x576 anamorphic picture, resizes it to 720x432 (sorry, it was 432 and not 406, I just mistyped) and black bars are added. I think, you just misunderstood me.

All 2,35:1 PAL DVD movies I've seen till now were encoded 16:9 anamorphic. I noticed that NTSC DVDs have 2 versions (always looking in online shops :D), one widescreen and one "normal" version. Sorry that I havn't specified this more specifically. Seems like you done the job :D


@ NearlyCritical
You're talking about that *PARTICULAR* TV.
Normal 4:3 TVs with 16:9 mode don't do what you saw on that SONY site ;)

[Stampede]

Yup, it's true that $100 special I bought at Wal-Mart for my computer room sure doesn't have the snazzy decode features ;)

[NearlyCritical]

@ DJ Bobo

I just used the Sony site to demonstrate what widescreen mode does on a 4:3 TV. LG and JVC also have this feature.

So what does widescreen mode do on other TVs??

[Stampede]

@NearlyCritical
The first link in my first post answers your question to Dj Bobo I think. The second set of pictures shows a 4:3 television demonstrating how it displays letterbox widescreen vs anamorphic widescreen. Then the 3rd set of pictures shows a 16:9 television demonstrating how it displays letterbox widescreen vs anamorphic widescreen.

[NearlyCritical]

@ Stampede

I have checked out the links you provided and they describe the difference between anamorphic and non-anamorphic on a standard 4:3 tv.

This is not what I am describing. Many 4:3 TV now have a widescreen mode. This means that instead of the dvd player performing a mathematical downconversion and then passing a 4:3 image to the TV, the full anamorphic image is sent to the tv (as if its really a 16:9 widescreen tv) and the tv focuses all the vertical resolution to the centre of the screen. The result is much better picture quality.

My original suggestion is to encode to divx using the full anamorphic resolution and pass this to a 4:3 tv with the widescreen mode to greatly improve picture quality.

[Stampede]

@NearlyCritical

I'm sorry I didn't understant what you were saying at first. I didn't know you had a 4:3 TV with its own widescreen decoder mode. Hehe I've never even seen one of those before. I think you're right that compressing an anamorphic movie in that resolution might look marginally better on your TV's widescreen mode. If your interested in quality you'd want to keep a similar quantinizer and I don't think the increase file size is worth it.

[NearlyCritical]

Yes, I am still testing to compare quality and how much extra bitrate is needed. I am hoping the results should be quite noticeable considering its 2x the vertical resolution.

[bb]

Originally posted by NearlyCritical
This is not what I am describing. Many 4:3 TV now have a widescreen mode. This means that instead of the dvd player performing a mathematical downconversion and then passing a 4:3 image to the TV, the full anamorphic image is sent to the tv (as if its really a 16:9 widescreen tv) and the tv focuses all the vertical resolution to the centre of the screen. The result is much better picture quality.

My original suggestion is to encode to divx using the full anamorphic resolution and pass this to a 4:3 tv with the widescreen mode to greatly improve picture quality.
Well, I just wanted to confirm that. My Grundig TV set does the same thing when switching to 16:9 mode. When recording DVDs on VHS tape I switched off the DVD player's internal downsizing to get the anamorphic picture through to the VCR. During VCR playback I switched to 16:9 and got a much better picture.

The same can be done for DivX films. But: if you use the same bitrate to get the same filesize compared to non-anamorphic encoding, you'll get more blocks / higher quantizers. You may want to smooth more, but I don't know if the overall picture quality will be better when downsizing with the TV set's 16:9 button.
If you use a higher bitrate to get the same quality as in a non-anamorphic encoding, then your filesize will be much bigger. You may find a good compromise, though.

Personally I prefer to encode to 1:1 aspect ratio, which is best for computer monitors. For TV playback I let the player compensate for the pixel aspect ratio (1.1 : 1 for PAL). ZoomPlayer has a global setting for this (set it to 10% for PAL and you're fine).

bb

[DJ Bobo]

Still it's not common to all TVs. That focusing feature is only available on selected TV-Sets, not on all of them.
We've got a THOMSON TV-Set with a 16:9 mode, and it doesn't focus anything, it just resizes down.

[manono]

Hi-

Still, if NearlyCritical's and bb's and other's high end 4:3 sets can do that, it'll give a major quality boost for anamorphic DVD material. I didn't realize that was possible until NearlyCritical provided the link explaining it, so I owe him an apology for doubting his word. Sorry, man.

But to encode DivX5 at anamorphic resolutions may or may not be worth it. As bb said, and I implied earlier, you'll take a major quality hit for the same file size. I think that to take advantage of the feature, what were before 2 CD movies, will have to be done for 3 CDs when encoding at anamorphic resolutions.

[grahf]

If you have a 4:3 tv capable of this 'widescreen mode' (such as my 27" Trinitron), all you have to do is turn on the feature, then use zoomplayers 'anamorphic' aspect ratio option. I do this for all my movies, dvd or divx, and while it might look a bit better if you encode specifically for anamorphic use, most divx's still look ALOT better if you use zoomplayer + widescreen mode on your tv. The difference in resolution is instantly noticeable, even to non-technical people.

[NearlyCritical]

@ manono

no problem mate .... I am happy if the knowledge of this forum grows and discussion and debate is how its done. :)

[MvB]

@NearlyCritical:
The link you provided is only relevant for this particular sony TV, which is capable of displaying 1250 lines. It resizes, if i understand correctly, the anamorphic picture to is original ratio but with a much higher resolution than 576 lines. So no information of the picture will be lost after adjustment of the ratio. But this is a special way of displaying anamorphic pictures correctly. All (i repeat ALL) other TV Sets i know do it differently AND the same way:

They reduce the spacing between the lines, meaning the your electron beam doesn't pass the whole screen vertically anymore, so that the picture will be reduced vertically by the correct amount. The Advantage to a 4:3 picture sent to the TV by your DVD is at hand:
- First, your picture on the screen will have about 25% more resolution in 16:9 Mode because it displays all the lines of the anamorphic picture. In contrary the dvd player jumps over every fourth line (not sending it to the TV) to archive 4:3 aspect ratio in non anamorphic mode. You see, an anamorphic picture adds lines that wouldn't be there at a 4:3 picture. If you discard every 4th line you get your normal 4:3 picture on a 4:3 screen.
- Second, the picture is looking better because of 2 things:
1) The resolution enhancement
2) The lines in 16:9 mode are far more invisible than in normal mode because of the reduced space between them (You know, the steps on the edge of things become much smaller)

So, even if your anamorphic encoded divx doesn't have a better picture quality your would'nt see the line in the TV picture so much, which enhances picture quality a great deal.

MvB