16:9 to 4:3

[alexx7777]

please tell me how to translate 16:9 to 4:3 (Original 1920x1080 50 p 16:9, target 720x576 4:3 50 p)

[Mystery Keeper]

please tell me how to translate 16:9 to 4:3 (Original 1920x1080 16:9, target 720x576 4:3)
The idea itself is very bad one. I would suggest you simply resize it to 720x576 (my choice is Spline64Resize), but set DAR (Desired Aspect Ratio) in container to 16:9. That way you preserve as much definition as you can, the video will be displayed correctly on 16:9 monitor, and on 4:3 monitor it will be automatically letterboxed with black borders.

[alexx7777]

Thank you, Mystery Keeper, I do for TV 4:3, what is a good way to remove these black parts?

[manono]

...what is a good way to remove these black parts?
Do you consider chopping off the sides of your video so it fits your 4:3 TV set without black bars a good way? You'll lose something like a third of the picture. And when you get a 16:9 TV set in 6 months, a year, two years, then what? Then you'll be complaining about the black bars on the sides of this video you made?

[Mystery Keeper]

Thank you, Mystery Keeper, I do for TV 4:3, what is a good way to remove these black parts?

I already told you, there's no good way. Your video will be padded with black borders for whatever aspect ratio display has. You could stretch it instead. But that would look like an ugly distortion. You could crop it. But you'd just lose part of your video, and it still would be padded with black borders on other display.

[manolito]

I would suggest you simply resize it to 720x576.

According to sneaker_ger (or was it TheSkiller?) it is better to resize to 704x576 to preserve the correct aspect ratio.

And the correct way to display a 16:9 movie on a 4:3 display is to have black borders on the top and on the bottom (letterboxed).


Cheers
manolito

[TheSkiller]

According to sneaker_ger (or was it TheSkiller?) it is better to resize to 704x576 to preserve the correct aspect ratio.That must have been me. :D
Yes, there are at least 2 good reasons to prefer 704 over 720, but we have dicussed this numerous times here on doom9.
I personally do it all the time for everything I put on DVD, the only exeption are the DVD menus because many standalone players somehow place the subpics (button highlights) with a slight offset if the video is 704 (nothing one needs to worry about for subtitles, but button highlights need to be exactly where they are supposed to).



And the correct way to display a 16:9 movie on a 4:3 display is to have black borders on the top and on the bottom (letterboxed).
Usually yes. But there are exceptions – for example 16:9 footage which was shot for TV is very often (especially in the USA) shot in a "4:3 safe" fashion. That means it can be cropped to a static 4:3 frame in the middle (called center cut) and you still wouldn't lose any mandatory picture parts or miss any text overlays.
Note that this is not the same as the (awful) Pan and Scan process which cuts down a movie as wide as 2.39:1 to 4:3 by panning across the frame.


So, basically, making a 4:3 version from your 1920x1080 50p source is only a good idea if, and only if, it has been produced in 4:3 safe and of course it all makes sense only as long as it is going to be watched on a 4:3 TV. By the way, I still only have a 4:3 TV, too. :)

Why are you going for 50p? If you intend to put it on DVD, you will have to interlace it to 50i/25.


Crop(240,0,-240,0) #crop to 1440x1080 (4:3)
BlackmanResize(704,576, taps=4)
Blur(0, 0.6).Sharpen(0, 0.4) #mild vertical low-pass

AssumeTFF()
SeparateFields().SelectEvery(4,0,3).Weave() #interlace it

[pandy]

From approx 1990 any European TV should be capable to display 16:9 automatically (or by WSS or by SCART Pin 8) - video will be squeezed in analog way (no vertical resolution loss).
Go for 704 (720) with anamorphic.

[TheSkiller]

Yes (well, usually not automatically but by WSS and/or Scart Pin, and some do not read WSS at all), but if the video was actually produced in a 4:3-safe fashion it is a plausible thing to make a 4:3 video for display on a 4:3 TV from it because watching a video produced with center cut for 4:3 display in mind in letterbox would be nonsense (pretty much), even if there's no resolution loss using the TV's squeeze. :)

If we're talking about DVD (are we?) of course one can still just make an anamorphic 16:9 encode but with PanScan sequence display extension and allow PanScan in the IFOs. This will give exactly the same result on a 4:3 screen as a "real" cropped 4:3 encode in 704 or 720 except – of course – for one thing: horizontal resolution is reduced to 75%.

Ideal solution (if you have enough space on the DVD), make two versions (anamorphic 16:9 and cropped full resolution 4:3). Probably sounds overkill to most of you, but I do this whenever possible and feasible.

[robertcollier4]

Original 1920x1080, target 720x576

If you don't want to cut the sides, you could do this:
Spline64Resize(720,405)
AddBorders(0,85,0,86)

[paradoxical]

Yeah, but that loses vertical resolution and still has black bars which is what he's saying he didn't want. The only way to get what you want alexx7777 is to blindly crop it to 4:3 or do your own pan-and-scan so you can at least not crop away what could be the main focus of the scene. Both of which will look pretty horrible with the 25% picture loss, though.

[robertcollier4]

I don't understand about "loses vertical resolution" -- if his display monitor is 720x576 then his player software is going to do that downsizing anyways - and its better that he does it with Spline64Resize rather than the (inferior) algorithm that his (hardware) player uses.

If preferring to lose the sides instead of adding black bars, then I recommend:
Crop(285,0,-285,0)
Spline64Resize(720,576)


My personal preference is to use Spline64Resize for lowering resolution and Lanczos4Resize for raising resolution.

[paradoxical]

I don't understand about "loses vertical resolution" -- if his display monitor is 720x576 then his player software is going to do that downsizing anyways - and its better that he does it with Spline64Resize rather than the (inferior) algorithm that his (hardware) player uses.

Because an anamorphic encode has more vertical resolution than the 405 in your script. What did you not understand? Also, it's quite doubtful on some old analog 4:3 TV he will notice the difference between the player resizing and Avisynth resizing. So to make it future proof for if/when he gets a 16:9 TV as manano suggests, doing anamorphic would be better than to already lower the vertical resolution by around 30% and letterbox it. On such a TV he will also have to zoom the picture or live with the fact that it will then get pillarboxed to fit the 16:9 TV. Basically making it look even more hideous than just doing a proper anamorphic 16:9 encode.

If preferring to lose the sides instead of adding black bars, then I recommend:
Crop(285,0,-285,0)
Spline64Resize(720,576)


Which is actually the worst of all options. Blindly cropping to 4:3 means you'll likely crop out the focus area of more than a few scenes.

[robertcollier4]

Also OP - if your monitor is 720/576 that is 1.25 aspect ratio, so you saying you want 4:3 (1.333 aspect ratio) is incorrect.

[paradoxical]

Also OP - if your monitor is 720/576 that is 1.25 aspect ratio, so you saying you want 4:3 (1.333 aspect ratio) is incorrect.

He quite clearly said 4:3 TV.

[TheSkiller]

Neither TVs nor monitors are 720x576. It's way more complex than that. ;)

Blindly cropping to 4:3 means you'll likely crop out the focus area of more than a few scenes.
I still feel like having to throw this in again: this depends on whether the video is intended to be 4:3 center-cut compatible or not. If it's not then it's simply 16:9 and cannot be made 4:3 fullscreen in a sane way. It's as simple as that.

[paradoxical]

Neither TVs nor monitors have 720x576. It's way more complex than that. ;)

The question asker was clearly not saying their TV was 720x576. They were referring to the final resolution of the DVD.

I still feel like having to throw this in again: this depends on whether the video is intended to be 4:3 center-cut compatible or not. If it's not then it's simply 16:9 and cannot be made 4:3 fullscreen in a sane way. It's as simple as that.

Making a widescreen movie into 4:3 Fullscreen isn't sane regardless of how the movie was shot.

[TheSkiller]

Making a widescreen movie into 4:3 Fullscreen isn't sane regardless of how the movie was shot.I have to highly disagree, but it seems we're not talking about the same thing. You are talking about the awful Pan and Scan process used (in the past) to transfer movies to TV, VHS and DVD, I don't.

First, the OP never made it clear what kind of video we're talking about (movie? TV show?).
He also never made it clear whether or not he wants to make a DVD. He said he wants 720x576 50p which is not DVD compatible.

If it's a movie shot for theater presentation I would absolutely agree – it was definitely without a doubt not produced with 4:3 safe areas and as such I wouldn't ever consider butchering it into a 4:3 fullscreen frame a sane thing.
However, TV shows, news, basically everything produced in 16:9 for the TV market may be shot and edited with 4:3 center cut in mind, and as such it would be a sane thing to crop it to 4:3 if there is a need for it because it was intended to be viewed this way as well.

[paradoxical]

Sure, 50p isn't DVD compatible. But if the end result wasn't for a DVD what would be the point of wanting to resize to PAL DVD resolution? It's quite clear what the end result will be even if they got the frame rate wrong. They weren't saying anything about the TV being a resolution of 720x576 which was the whole point of my comment above. Considering they said this is will be watched on a 4:3 TV it's doubtful they are playing this off of a PC (if they were there would be no point even resizing it to begin with to reencode it'd be resized when output to the TV). So it's either got to be a DVD or their going to be playing this off a some media player.

[TheSkiller]

Yeah, I was suspecting that as well (hence my script suggestion in post #7 to make it 50i/25 for DVD). :)


Oh, it seems we were misunderstanding each other. :D

My comment about 720x576 not being the "resolution" of a TV or any monitor was a reply to robertcollier4.
Also OP - if your monitor is 720/576 that is 1.25 aspect ratio, so you saying you want 4:3 (1.333 aspect ratio) is incorrect.