Guessing values to transform 1:1 into Anamorphic

[Episodio1]

I'd like to encode an XviD 1:1 into an anamorphic DVD.

I'm using CCE but I can't guess correct values of the vertical resolution to get proper image.

What resolution should I write into the AVS if my XviD source is 640/336 (1'906) ?


Thanks.

[Skelsgard]

With a 640 x 336px it´s most likely to be 16:9 (perfect 16:9 would be 640 x 360px).

For NTSC 16:9, the DAR would be 854 x 480px.
And 854 x 336 / 640 = 448px. 480 - 448 / 2 = 16px.
Resize the file to 720 x 448px and add 16px of borders in the top and the bottom.
In your script:
BicubicResize(720,448)
AddBorders(0,16,0,16)

For PAL 16:9, it would be 1024 x 576px.
So, 1024 x 336 / 640 = 538px. 576 - 538 / 2 = 19px
BicubicResize(720,538)
AddBorders(0,19,0,19)

You might wanna try some smart sharpening filters like SeeSaw to improve your video after the resizing.

Cheers.

[scharfis_brain]

these resizings aren't ITU conform.

you need to scale to 704 pixels width instead of 720 pixels width...

[Skelsgard]

What resizings? 720x576 isn´t ITU conform? And why 704 if only Full-D1 can be 16:9?

[scharfis_brain]

http://www.haku.co.uk/ARCT.html

http://lipas.uwasa.fi/~f76998/video/conversion/

[Skelsgard]

So basically, he must use a 704x576 resolution and create a 704x576 DVD.

[Episodio1]

Same deal with the software DVD players resizing vs ITU conform, isn't it? Is it so important to fullfill ITU?


Skelgards, I have tried seesaw for first time but I only noticed the first frame as shaperned, not the rest. :? I'll take a look.

[Skelsgard]

With all due respect, when I´have never in my life seen a 704px DVD (which by definition means "every single DVD" I own and have come across ever is 720px) why pushing a 704px ITU standard?

@Episodio1
I learned about SeeSaw in this thread http://forum.doom9.org/showthread.php?p=862199#post862199, and used Pookie´s method with MVTools + RemoveGrain + SeeSaw and never came back to my prior methods for cleaning sources. I actually have a great deal to thank Pookie for that method, and of course Didée for coming up with SeeSaw.

Cheers.

[scharfis_brain]

One still can use 720 pixels width.

Either by adding 8 pixels each side to your 704 pixels wid image, or by recalculating the active image area:

NTSC: 720x459
PAL: 720x551

Actually I've seen some DVDs containing stuff in 704 pixels width. It is fully compatible and allowed to use. So why don't use it.

[Skelsgard]

One still can use 720 pixels width.

Either by adding 8 pixels each side to your 704 pixels wid image

Why would you wanna do that? Does it involve some sort of "safe-area" concept? (Bear in mind, although you can´t hear my tone of voice, I´m asking out of curiosity). I read the links you posted, they also state 720 as DVD resolution (Full D1). That´s why I wonder why force the 704 standard over the 720, what is there to gain that I´m not seeing?

Cheers.

[scharfis_brain]

4x3 PAL in square pixels is 768x576
translated to D1 this becomes 702x576 (seven zero two!).
to make this 4x3 PAL conforming MPEG-able resolution it has to be padded to 704 (adding 1 each side) or 720 (adding 9 each side) pixels width.
resizing 768 dfirectly to 720 WILL result in an aspect ratio error.

so the backwards conclusion (for displaying a 4x3 PAL video in a square pixels monitor):
702x576 has to be scaled back to 768x576 (AR: 1.333:1)
704x576 has to be scaled back to 770x576 (AR: 1.337:1)
720x576 has to be scaled back to 788x576 (AR: 1.368:1)

so: 720x576 actually is MORE WIDE than real 4x3.
704 can be used as approximation of 702, but not 720.

so in the case of resizing avis to dvd, I still recommend 704, cause it will have the same active picture area
(a tv will ALWAYS crop away the 9 pixels left&right on 720 pixels width video)

[Skelsgard]

Isnt´the decoder/renderer gonna DAR-it to 4:3 anyway, independently of the resolution?

[chipzoller]

scharfis, if you're still monitoring this thread, I'm really having some difficulties understanding resizing (albeit opposite of the aim of this thread; from DVD -> PC ) and was wondering if you could supplement what the other posters in the thread have said and perhaps see if you can clue me in a bit better. One of the things I can't quite understand is how PAR relates to aspect ratio in square pixels. Anyway, if you can take a look I'd really appreciate it. -Danke