16:9 to 4:3 ?

[yukon33]

I am about to shoot a demonstration video which will be streamed on a website on a 4:3 standard player.

I am using a wide-angle lens, because width of coverage and the portrayal of 'space' is very important. It seems logical then that I should also shoot in 16:9.

My question is: how do I retain my 16:9 aspect ratio on the 4:3 media player, without any cropping?

What I mean is, I understand I need to shrink the 16:9 picture a certain percentage to get it to fit horizontally into 4:3... but how do I go about this - how do I 'pull it in' correctly and get the black bars to fill in the top and bottom of the screen?

So far I have experimented with importing 16:9 footage into a 4:3 project in my editor (Liquid Edition), but because ratio is set at 4:3 the sides of my wide footage are simply cut off (when I try to shrink the picture the sides are gone and cannot be 'brought into frame'). Yes I could start a 16:9 project and shrink the picture within that, so that when it plays on a 4:3 player it looks 16:9 with black bars, but how will I know when I have made the correct adjustments to fill the 4:3 size, since the editor will be in 16:9 mode?

I hope what I need to fathom out is clear enough here. I have seen many examples of 16:9 films appearing in YouTube's 4:3 frame all present and correct, with the requisite black bars at top and bottom.

Any help much appreicated!

[guns1inger]

I assume you are shooting true 16:9 anamorphic, so your framesize is 720 x 576. You need to resize the vertical to 432 lines, then add 72 lines of black above and 72 lines of black below to get back to your full frame size. You now have a PAL 1.778 : 1 widescreen video in a 4:3 frame. You can now do whatever else you need to encode this for streaming.

For NTSC you would resize the vertical to 360 lines and add 60 lines of black to the top and 60 to the bottom.

[manono]

FitCD resizes to 720x368 and adds back 104 rows of pixels to both the top and bottom for PAL 16:9 to PAL 4:3.

Going 16:9 to 4:3 isn't just the reverse of going 4:3 to 16:9.

Edit later: Ignore this as it's wrong. See my next response below.

[yukon33]

Thank you both, I still am a bit confused after some basic experiments in Liquid Edition.

First of all I do not believe my Canon XM2 shoots true anamorphic 16:9? Or am I wrong?

Okay so I would expect it at least to provide a 'squeeze' option (like my cheap JVC palm camcorder) so I can shoot 'more' either side of the picture than in normal 4:3.

But when I have digitised and compared in a 4:3 window shooting the same scene in 4:3 and 16:9 on the Canon, the only difference in changing the 16:9 footage to its 'original ratio' is black-bar cropping at the top and bottom... no 'extra' picture at the sides?? As if shooting in 16:9 simply means losing a bit at the top and bottom of the picture with this camera? Surely not.

Properties of the test footage tell me yes the 16:9 footage is 720 x 576, but so is the 4:3 footage - exactly the same size in its properties.

What can I be doing wrong - why are the 4:3 and 16:9 picture both displaying the same 'original image size'... and how can I get my picture wider? Or is this as wide as it will go, and is 4:3 for some reason giving me the same 'wideness' (and extra at the top!)?

Sorry if these appear to be dumb assumptions.



p.s. UK PAL format

[manono]

And I'm afraid I'll have to retract what I said. I had FitCD set up wrong. Unfortunately you replied before I could get back an hour or so later and edit (or remove) the response. Using ITU resizing, guns1inger is 100% right. Sorry.

I don't have your camera, and don't know if it's shooting real 16:9. If you want to upload a small piece of a video, we could have a look, or maybe someone with that same camera can comment.

[yukon33]

No problem -

Very keen to clarify this simple issue I have now though...

I thought I could get more picture wideness shooting in 16:9, but I only seem to be losing footage from the top!

If someone understands the XM2/GL2 perhaps they could help? Or is my old editing software playing up in telling me even my 4:3 footage is 720 x 576? This size is meant for 16:9 and not 4:3?


Edit: When I flick between the 16:9 'on' and 'off' in the camera onscreen menu, the viewfinder simply stretches the picture vertically and back again. There is no change in horizontal picture, such as the 'squeezing in' of more side footage I would expect (as my JVC does when I switch between normal and 'squeeze').

[manono]

DVD resolution for both 4:3 and 16:9 encoding is 720x576. It's how it's resized at playback time that makes the difference. Again, though, unless someone comes along that has that camera, maybe the best way to figure out what you're capturing is with a small sample.

There are 2 ways it could be switching from 4:3 to 16:9. One would be to keep the vertical picture the same and show more from the left and right sides, as you seem to expect. The other would be to keep the left and right constant and crop from the top and bottom, which seems to be what it's doing. I don't think either would be incorrect.

[yukon33]

OK I have to get this project going ASAP so I am going to stick with 4:3, if all 16:9 seems be doing is cropping the top and bottom....

I will come back to this issue very shortly and provide some video samples so you can see exactly what I am talking out, then hopefully we can get to the bottom of it!

Cheers

[guns1inger]

16:9 -> 4:3 Letterbox should not involve any cropping. It is resizing vertically to adjust for the Pixel Aspect Ratio changes, then adding bars to get back to a 4:3 frame. You should not have to crop anything.