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View Full Version : Keeping Aspect ratio with Avisynth in DVD2SVCD


turluson
23rd January 2002, 21:11
I'm using the new version of DVD2SVCD (1.0.6 build 1). This version include a AVI2SVCD option ..WOW :D :D :D This option works great to convert Divx to svcd. AVI2SVCD alow you to edit the Avisynth script file during the conversion.

I want to conserve the aspect ratio of a 16:9 (576x256) divx movie. (I don't want egg head). Does someone can explain me how edit the avisynth script file to do this. Thanks !

kdiddy
23rd January 2002, 21:38
16:9 ratio is 1.777....so as long as your horizontal vs. vertical resolution is at least 1.777..then it will be 16:9...cinemascope (aka anamorphic widescreen)is 2.35...EXAMPLE: I do my SVCDs at resize 480x270 (480/270=1.77)..then add the black borders to raise it back to 480x480.

Kedirekin
24th January 2002, 00:15
Oops! I don't think that is right.

Don't forget that the player (software or hardware) should apply a dar (display aspect ratio) transform on playback so that 480x480 will have an aspect of 4:3 (equivalent to 640x480). Your 480x270 mpg will be transformed to the equivalent of 640x270, which gives an aspect of 2.37:1.

For 16:9 (1.777:1), you want to resize to 480x360, then add borders to get to 480x480. On playback, this will be transformed to the equivalent of 640x360, which is 16:9.

Similarly, for 1.85:1, you want to resize to something close to 480x346. And for 2.35:1, you want to resize to something close to 480x272.

kdiddy
24th January 2002, 07:24
No it is right....using the ratios I said with a 4:3 DAR, will give the "4:3 letterboxed" option look on a regular TV (well it does on mine with my player), which it was my understanding is what the poster wanted....using the 480x360 ratio with a 4:3 DAR gives the "16:9 widescreen" look (ie, the stretched "egghead" look) on regular TVs.

Kedirekin
24th January 2002, 13:32
Sorry, kdiddy. We'll just have to agree to disagree. I simply don't agree that 480x270 is correct resize for a 16x9 SVCD.

kdiddy
25th January 2002, 06:22
well it is..using a 4:3 DAR only ..not using a 16:9 DAR...use DVD2AVI 1.82 yourself and you will see the difference.

Trahald
13th February 2002, 05:06
i have a dvd im backing up now which is 1.85:1 (says so on the dvd cover) -- anamorphic 16:9

im using 480x346 + black bars (from a tutorial i read) looks as close as i can perceive(sp) by eyes to the right aspect.

this dvd was fun... if it were the first i tried i would return my dvdrom

its multi angle seemless branched (so have to rip it right or you get sorta a deja vu repeating playback. plus it needed ivtc which adds more time to encode!! and on top of that i had to figure out AR cause its 16:9(above).. eek!!!