DVD open matte 1.33 to 1.85
#1
I watched Miracle Mile (1988) from a FS copy i found on TPB HERE

Effing great movie, i wanted to keep it for my collection so i found a DVD to encode.
The point is the DVD is also FS but in the beginning of the movie this text appears

[Image: vlcsnap_00010.jpg]

Not much info about the DVD release but i found THIS thread

If i understand the terms correctly:
Pan and scan DVDs: info is cropped out from left and right and it's made in a way so as the image fits the old 4:3 TVs

open matte: you get more picture top and bottom so the image again fits 4:3 TVs

So if this movie was originally shown in theaters as 1.85 AR, as IMDB says and also some members on the thread i linked above, by cropping it,provided that the dvd is open matte, i actually achieve OAR?

Long story short

Screen from DVD
[Image: vlcsnap_00006.jpg]

Resized and cropped
[Image: 32039.jpg]


I'm definitely doing it at 1.85 for my collection but if i decided to share it too would you say this is overcropped or actually presenting the movie in the OAR?
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#2
if the dvd is open matte, then the cropped version is oar.
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#3
One question in case you can help m8, because i want to be sure i won't fuck this up.
Mediainfo from VOB file

Width: 720 pixels
Height: 480 pixels
Pixel aspect ratio: 0.889
Display aspect ratio: 1.333

If i'm not wrong: DAR = PAR x SAR = 0.889 x (720/480) = 0.889 x 1.5 = 1.33

Let's assume the video has no black bars to crop out, there's only the cropping to frame the open matte back to 1.85 AR

DAR = 720x540 i want to change that to 720 x 390= 1.846 AR

I need to crop out from the height 540-390 = 150 pixels

I multiplied those pixels with PAR so i cropped out 150 x 0.889 = 133.35 ~ 134 pixels

Then resized to 720 x 390

Is this the way to do it?
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#4
you forgot to account for the 8 black pixels you seem to have cropped from the left side of the frame.
what you need to crop from the top and bottom, then, is 137 pixels.
if you need to work with even numbers go for 136.
a good choice is to crop 64 on the top and 72 on the bottom.
that would leave you with a 712x344 frame.
once resized to 720x390, the AR error will be (as near as makes no difference) 0.
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#5
I didn't forget the 8 black pixels, that was my nest question and it's the last one, sorry to bother you m8 Big Grin

Enter the 8 cropped out pixels from the left of the frame and the fact that i'm resizing to mod16 704x384=1.833

I did the encode with 134 black pixels cropped out and something didn't seem right.
It feels better to the eye with 130 or 132 pixels cropped.

Is this due to the fact that i'm not resizing to exact 1.85 resolution?

I mean to resizing to 1.833 instead of 1.85 would mean less pixels cropped out?

It feels that way to the eye.

[Image: image.png] [Image: image.png]

[Image: image.png] [Image: image.png]
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#6
considering the new 704x384 resizing then instead of 137 pixels, you'd have to crop 135.
you could still round it to 136 or you could go for 134.

also, i'm a freak - when i encode for my own consumption i go even further.
in this case, i wouldn't reduce the cropping to 132 or 130.
i'd go for 112~116. i like a bit of horizontal stretching.

it doesn't matter if you're not aiming at precisely 1.85, you could even go for 1.77 or 1.66,
all that matters is that you crop accordingly.

update - out of curiosity, i overlayed a perfect circle over the moon
on both the 132-px-cropped and 134-px-cropped pictures you've provided.
the 132 was perfect, the 134 was off by a minuscule amount.
having said that, i don't know if the actual moon is perfectly round. i know the earth isn't.
anyways, this serves to prove that dvds don't always have absolutely perfect aspect ratio.
in this case, i suspect that IF the picture had been stretched to fill those black pixels on the left,
THEN you'd have perfect aspect ratio on the dvd.

edit - and if my suspicion is correct, and i believe it is,
then the correct number of pixels to crop for an aspect ratio of 1.833 would be 131,
which you'd round to 130 or 132.

which, in turn, leads me to:

(Dec 29, 2013, 14:38 pm)asterastrip Wrote: It feels better to the eye with 130 or 132 pixels cropped.

damn, you have good eyesight!
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#7
Thanx very much for taking the time m8, i'll do it again cropping out 132pixels and it feels pretty accurate.
Fuck it if it's not perfect, it's watchable.

I also had to do a script with 33 different trims and cropping to properly reframe the crop window up and down throughout the movie otherwise i got missing info on some scenes which tells me the DVD probably isn't open matte.

Using 1 fixed cropping for the whole movie

[Image: image.png]

Multiple adjusted cropping through the movie

[Image: image.png]

Safe to say the DVD isn't open matte and i actually crop something already overcropped ?
I don't know about open matte DVDs but i reckon if this one was indeed open matte then i wouldn't have to adjust the crop window.
A single fixed cropping for the whole movie would do the trick and it wouldn't result in faces in the frame without eyebrows or mouths Tongue
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#8
(Dec 29, 2013, 17:38 pm)asterastrip Wrote: Safe to say the DVD isn't open matte and i actually crop something already overcropped?

hard to say without comparing to the original print (not resized to fit old crt tv sets)
but considering all the cropped mouths and eyes, you may be right about that.

(Dec 29, 2013, 17:38 pm)asterastrip Wrote: I don't know about open matte DVDs but i reckon if this one was indeed open matte then i wouldn't have to adjust the crop window.

sounds very logical. keep in mind, though, that open matte doesn't necessarily add extra frame in a strict 50% top / 50% bottom proportion.
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#9
Thanx very much for taking the time m8 Smile
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#10
* NIK wishes all threads could be this epic
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