AR 1.78:1 vs 1.85:1

[leonb]

What is the correct AR for a "16:9" movie? When I play it from the dvd disc, it is stated (zoomplayer) that the AR is 1.78:1. When I want to rip the movie with GK, GK gives the AR of a "16:9" movie as 1.85:1 (actually 1.82:1) - so it calculates the AR ackordingly, 480x256.

When watching the ripped (divx) movie, the AR is know 1.85:1. The black bars is definately a bit bigger than when watching from the dvd disc. I actually measured the movie size on the pc monitor with a measuring tape and the dvd movie is definately 1.78:1, where the divx movie is 1.85:1. Personally I feel that the 1.78:1 AR is the correct one, as that is the way any standalone dvdplayer will display it on a tv.

So why does everyone feel that the movie should be encoded in a 1.85:1 AR?

Flame me if you want - if you feel this was explained numerous times before :)

[Soulhunter]

Not flaming you... :D

16 : 9 = 1,7777777777777777777777777777778

Originally posted by leonb
...GK gives the AR of a "16:9" movie as 1.85:1 (actually 1.82:1) - so it calculates the AR ackordingly, 480x256.
One reason for changed AR could be that you have used the crop function... ;)

But here it looks like 480x256 is simply a "rounded to mod 16" result !!!

480 : 16 = 30 | 30 x 9 = 270 | 270 : 16 = 16,875

270 would be the real horizontal resolution !!!

But its not a multiple of 16... ;)

No matter, instead of 256 I would use 272, as Its closer to 270 !!!

No wait, I would use a resolution of 1024x576... :p


Bye

[Mnl]

Hi leonb

If you want to know more about AR's then I'd first recommend you to read this:

Aspect ratios explained (http://www.doom9.org/aspectratios.htm)

And when you're done reading that read this thread:

Resolutions, Aspect Ratios And The ITU-R BT.601 Standard (http://forum.doom9.org/showthread.php?s=&threadid=42708)

In this thread there's a link to this wonderful explanation (http://www.uwasa.fi/~f76998/video/conversion/).

These threads/documents will answear your question (and a lot more) :)

hth

Mnl