Letterbox to 16:9 conversion?

[dvd3500]

Hi All,
I have a letterboxed LaserDisc NTSC capture with massive black bars.
I want to convert it to true 16:9, if possible but my brain is getting all screwy with how much to chop, crop and stretch.
I have read pages and pages about things but am still confused...
Thanks in advance.

[guns1inger]

What is your goal ? Do you want to author a 16:9 disk, but keep the original aspect ratio of the movie ? Do you want to zoom in to the movie so it fills a 16:9 frame, even if it means sacrificing the ends of the frame ?

If you want a 16:9 disk that preserves the original aspect ratio of the movie, crop 38 pixels from the top and the bottom, then resize what's left back to 480. Encode with the 16:9 setting and author accordingly. This will soften the image to a degree, so you may need to sharpen it before encoding.

If you want to fill the frame, do the same crop, then zoom the image until it fills the frame to the top and bottom. Again, resize back to 480. This will soften is substantially because of the zoom and resize.

If it were me, I wouldn't do more than the first option. You lose enough quality cropping and resizing without throwing away a good chunk of the picture and applying a zoom.

[junkmalle]

I think guns1inger is wrong. Assuming a 720x480 frame size, cropping 38 pixels off the top and bottom will give you a frame aspect ratio of 16:9, not a final picture aspect ratio of 16:9 on TV. For a final picture aspect ratio on a widescreen TV you should cut 60 pixels off the top and bottom, then resize the remaining 720x360 frame back to 720x480.

That will still leave some black borders if the movie is wider than 16:9. But it' the way most commercial DVDs are made.

You are probably going to have problems with this because the laserdisc cap is almost certainly telecined film or fully interlaced. If it's telecined film you can restore the original film frames via an inverse telecine, but with interlaced footage you'll have to deinterlace which adversely effect image quality.

[dvd3500]

Hi Guys,
Thanks for the info so far.
Basically I have these "widescreen" captures in DV AVI that have HUGE black bars. I want to auther to a DVD that is a proper 16:9 DVD I do not want to lose an of the picture if at all possible so little black bars and bottom are OK but I would like to have as much pictrue as possible.

It is interlaced but because of the high quality of the capture (ADVC 300) I figure a slight "sharpness" (ever so slight) out to do it.

Out of curiosity, what would be the number to hack from a PAL capture?
Thanks tons!

[guns1inger]

I'm curious as to where the 60 pixels top and bottom come from. My 38 pixels comes form simple math 720 / 1.778 (approx 16:9) = 404. This means chopping 76 pixels in total, or 38 top and bottom. What's the math behind 120 pixels in total ?

[dvd3500]

The thing that is doing my head in is that 4:3 pixels are not the same as 16:9 pixels not to mention that NTSC and PAL pixels are like metric to customary...

[FulciLives]

Hi Guys,
Thanks for the info so far.
Basically I have these "widescreen" captures in DV AVI that have HUGE black bars. I want to auther to a DVD that is a proper 16:9 DVD I do not want to lose an of the picture if at all possible so little black bars and bottom are OK but I would like to have as much pictrue as possible.

It is interlaced but because of the high quality of the capture (ADVC 300) I figure a slight "sharpness" (ever so slight) out to do it.

Out of curiosity, what would be the number to hack from a PAL capture?
Thanks tons!

PAL is 72 from the top and bottom (assuming your capture is full PAL height of 576) ... you then resize the height from the cropped 432 back to 576 and that gives you 16x9 WS

NTSC is 60 from the top and bottom (assuming your capture is full NTSC height of 480) ... you then resize the height from the cropped 360 back to 480 and that gives you 16x9 WS

- John "FulciLives" Coleman

P.S.
Be carefull how you resize interlaced video !!!

[Abond]

I'm curious as to where the 60 pixels top and bottom come from. My 38 pixels comes form simple math 720 / 1.778 (approx 16:9) = 404. This means chopping 76 pixels in total, or 38 top and bottom. What's the math behind 120 pixels in total ?

It seems it comes from 640/1.778. Why so, I don't know.
Edit: Well, it seems this is related to pixel aspect ratio 1.1 in NTSC. 720/1.1/1.778
For PAL PAR is 0.9375, so 720/0.9375/1.778.

[dvd3500]

Be carefull how you resize interlaced video

Should I deinterlace first?

[Abond]

Here you can see how is looking wrong resized interlaced video. You should either deinterlace it, or separate the fields of the frame and resize them, or use the software with capabilities properly to resize interlaced video. I personaly am using avisynth for this task.

[dvd3500]

I am pretty good with AVISynth so I will probably use that. :-)

[FulciLives]

separate the fields of the frame and resize them

This would be preferred to deinterlacing unless doing an IVTC is a possibility.

- John "FulciLives" Coleman

[dvd3500]

Anybody have an AVISynth script handy just in case?

[junkmalle]

I'm curious as to where the 60 pixels top and bottom come from. My 38 pixels comes form simple math 720 / 1.778 (approx 16:9) = 404. This means chopping 76 pixels in total, or 38 top and bottom. What's the math behind 120 pixels in total ?

It seems it comes from 640/1.778. Why so, I don't know.
Edit: Well, it seems this is related to pixel aspect ratio 1.1 in NTSC. 720/1.1/1.778

Exactly. Since numerically 720x480 is slightly more than 4:3 the DVD player squishes width of the picture down to the equivalent of 640x480 for display. So base your 16:9 calculation on 640: 640 * 9 / 16 = 360. Subtracting 360 from 480 gives 120, split that between top and bottom to get 60 each.

[vhelp]

I used to beleive the same thing.. 720 / 1.778 (approx 16:9) = 404.
until one day, I realized it myself. Its all aspect ratio stuff you know.
Fulci (and DJrumpy, and a few others) corrected me on this in previous
responses, but I chucked it off to good old stuberness, till I realized
they were correct (and I was wrong)

Though the above is correct (mathematically) its not correct for a 4:3
Aspect Ratio Calculation Original View. (I can't put it in words)

But there are two kinds of widescreen aspect ratio calculations.

And they are:
* 4:3
* Anamorphic.

The 4:3 has to be 360'ed and resized to 480 resolution (be sure that you
are using 720 x 480 (not 352 x 480) and (note whether Interlaced)

As for Anamorphic, and depending on how it is obtained, (ie, captured or
dvd ripped) will have to be handled two different ways, though mostly
because of the odities of capture cards and how they Sample video and/or
then Cropped. (ie, some have there AR around 702; 704; 712; 720; etc)
And, last, there are those devices that have to have the AR setup correctly
before a proper capture can be made. (ie, DVD players have THREE AR
layouts.. letterbox; widescreen; enhanced. These are usually labeled
different from DVD to DVD player. But, for most cable/satelite boxes,
these usually output in Letterbox format, which would mean that you
would have to use the 4:3 calculation (mentioned above) for your project.
..and then these have to be either cropped and re-AR 'ed, or enlarged and
re-AR 'ed.

I didn't understand this, till I read somewhere's in passing
(a while ago) by fulci, where he stated he had to switch his DVD player to
the proper aspect ratio view. I think it had something to do with a DVD
test or something. Another fun experiement I guess. Anyways.

-vhelp 3357

[iThinkYouBrokeIt]

So it seems as though you have a non-anamorphic widescreen movie, and you would like to convert it to 16x9

If you are dealing with a PAL source, then de-interlacing shouldn't be an issue, as the image would likely be 25fps progressive - NOT interlaced.
If you are dealing with an NTSC source, then you should deinterlace, and TMPGEnc can handle this.
When you first load the file into TMPGEnc, change the "source settings" to say film. and in the advanced settings, select inverse telecline. this should deinterlace it and thus convert it to 24fps.

And yes, if it is NTSC, you should definately clip 60 from the top, and 60 from the bottom.
If it's PAL, then you should clip 72 from top, 72 from bottom.
... and make sure that in TMPGEnc's "clip frame - arrange setting" it is set to "full screen". This should be the default setting.

I think you should specify whether you have NTSC or PAL. A few people here (myself included) don't seem to know which it is...

[dvd3500]

I have a letterboxed LaserDisc NTSC capture with massive black bars.

Then I realized I have a few PAL VHS tapes "widescreen" that need converting so I figured I'd ask as well.
I use AVISynth, Vdub, Qenc and Media Studio Pro (got a really cheap upgrade) so I will proboble use AVISynth and Vdub for edit and Qenc for MPEG2 encoding.
Any thoughts on a an AVIsynth script would be great.

[iThinkYouBrokeIt]

yes... i guess i somehow didn't catch that the first time. it clearly says PAL

well yeah.....
I don't know about Vdub, AVISynth, Media Studio Pro....
i'm not familiar with those programs, except for Vdub.

[dvd3500]

It kind of says both. :-)

[Lap795]

Hi, quick question about letterbox to 16:9 conversion. I understand that if the source is ntsc you crop 60 from top and bottom and if pal 72 from top and bottom. My question is, how would this apply to a source that is pal but that I am converting to ntsc. Would I use the 60 or 72? Thank you.

[junkmalle]

Hi, quick question about letterbox to 16:9 conversion. I understand that if the source is ntsc you crop 60 from top and bottom and if pal 72 from top and bottom. My question is, how would this apply to a source that is pal but that I am converting to ntsc. Would I use the 60 or 72? Thank you.

72 if you crop before resizing, 60 if you crop after resizing.

[Lap795]

Thank you!