Content -> Scale to fit width/height

[funkytwig]

Hi, had a look in the manual but could not find info on this.

TLDR version, if I import a 16:9 video and use DCP Flat what should I do (I think I should end up with black borders left-right of image)

Full version

According to media info util, the file I have is 1920*1080.

In Content Tab->Video
I have 'Scale to set'=No Scale.
I have no cropping on this tab.
I am using DCP Flat and I get black borders top/bottom and left/right in DCP-o-Matic.

In the tab, I can see blacktop/bottom and left-right (top-bottom ones look around twice as thick).



So now to DCP Tab
Container=DCP Flat and has 1998x1080

Should I select Fit to Width or Fit to height? Both remove black borders left/tight.

Fit to Width gives me smallish top/bottom black border


Fit to height gives me bigger black borders (maybe twice as big).


What's got me confused is that I was expecting to see black borders left/right but not top-bottom when I put a 16:9 video in a Flat container as Flat is wider than 16:9. Something like this.


I am worried both Fit to the width and Fit to Hight are stretching images. I volunteer as a projectionist at a cinema and I have noticed left/right borders on 16:9 content (or I think that is what I remember).

Regards,
Ben

[jdent02]

The 'no scale' option looks to have the correct amount of black on the sides so I wonder if there are letterbox bars on the top and bottom of the original 1920x1080 video file.

[Carsten]

Left/Right black borders are pretty much accepted for HD content on flat screen aspect ratios. If you are doing this for your own cinema, your choice may depend a bit on your specific screen design (shape/aspect ratio, and wether there is masking/adjustable masking or not).

Maybe you can post a screenshot with 'Outline content' checked below preview.

Generally speaking, when using latest release version (2.14.xx), your best choice for moving image content would be 'No stretch' - then crop away what you don't need. The amount of cropping is variable, and you are free that way to keep all visible content, maintaining black bars on the sides, or fill the full screen proportionally by cropping away top/bottom without any distortion.

In current test release/release candidates, (2.15.x/2.16.x), choose 'to fit DCP' - and again, crop away as necessary.

Always use 'Outline content', so you can see wether your source contains any black bars. In most cases, they should be cropped away.

[funkytwig]

OK, so with no crop DCI Flat I get

Which I guess may fit 16:9 masking at the cinema (with black bard top/bottom) - if they even have masking which seems rare nowadays.

If I do scale to width (which changes Scale to 1:85 Flat) I get

which would be with flat masking.

Ime thinking of going for the latter.

Ime assuming the DCP-o-Matic scaler is very good otherwise the first option would be better,

I think the image part is probably 16:9 but there does not seem to be a 16:9/HD/1.85 container. Ime sure there used to be in DCP-O-Matic.

[Carsten]

We got rid of these unusual containers, as they are not strictly standard compliant. They wouldn't solve the issue, as, even with a dedicated 16:9 container, it is still your screen which defines the black bars.

Yes, this content does contain letterboxing in a 16:9/HD source. If you crop away the letterboxing, the image pipeline description on the left will tell you the actual aspect ratio after cropping - which I guess from the screenshot is just flat. So, you SHOULD be able to fill the full flat container, at least closely.


Don't use the quick scaling options ('scale to fit height/width'). They are quick'n-dirty shortcuts to fill the screen, but, they usually introduce distortion, and they won't work as intended anyway with letterboxed or pillarboxed content. Reset all scale/crop settings, choose 'no stretch', crop away the black bars roughly symmetrically from top and bottom, and you should be fine.

[funkytwig]

OK thanks, I have it set to No Stretch. Think the last post I made may not have been seen by you.

So is it better to use 1st option above (which does do scaling) or the second which crops out the bars and as a result, there is a bit of a zoom (which as I said I think is the better option as it gives a slightly bigger image and I am sure the zoom in DCP-o_Matic is great)?

I suppose ime kind of also also asking what a cinema would expect/prefer?

[Carsten]

My personal opinion on this is: If you create the DCP for your own (or a known) cinema, adjust the DCP to it's screen layout/masking. If the DCP is intended for a wider distribution and you can not control the way it is thrown onto the screen, stay with the standard aspect ratios flat and scope.

Admittedly, there is no easy answer how to deal with HD in flat containers - simply because small left/right pillarboxes for HD content are so common. The rights owner/creative decision makers should decide wether top and/or bottom should be cropped in order to fill a flat ar screen completely.

[funkytwig]

Been a while and it went fine.

I just realized something. At the community cinema, I used to help out they had to masking for left/right and top, but not bottom. In rare cases cinimas still have masking I think this is common os in a way hading the image at the bottom would be best.