4:3 -> 16:9 like some TV. How?

[tormento]

I'd like to restore some old tape cam video to be seen on wide screen. I can't find a proper filter to smart resize, like some LCD does, the format, i.e. almost nothing in center and more on sides.

Any idea?

[thetoof]

Do you mean you have a full 4:3 image you want to see on a 16:9 screen? By cropping you'd lose some of the image and by resizing you'd mess with the aspect ratio. Unless your source has black bars... more specs or a sample would be nice to help you more accurately.

[Alex_ander]

If you want numbers for going from 4:3 to 16:9 with correct proportions, this means cropping exactly 1/4 of image height + resizing back to standard DVD resolution (then encode with 16:9 AR setting). Don't crop anything else. Numbers don't depend on [imaginary] pixel type here. Take care of interlacing while resizing vertically (for interlaced use a smart bob before and re-interlace it after). An example for 720x576 source (with LeakKernelDeint):

LeakKernelBob(order=0)# 50p; '0' if BFF DV source
Spline36Resize(720,576,0,72,0,-72)
#ConvertToYUY2()
DoubleWeave()
SelectEvery(4,1)#TFF, 25i

[tormento]

No, what I mean is to use different aspect ratio for different horizontal areas of the frame. Have you ever seen a smart resize from a Sony LCD? It uses a 1:1 for the central area, where usually the faces are focused and gradually but not linear expand the aspect ratio to the sides.

[Didée]

http://forum.doom9.org/showthread.php?t=110833

http://avisynth.org/warpenterprises/#simpleresize

[pandy]

GreyC ? or something that have "Feature preserving resize" or just simple nonlinear resize like in TV?

[2Bdecided]

Just because you can, doesn't mean that you should! ;)

[shoopdabloop]

Pillarbox.

Distorting the edges makes pans feel very strange.

[wonkey_monkey]

I compromised with some 4:3 footage recently - I cropped to 14:9 then stretched horizontally to a 15:9 frame, leaving a very small amount of pillar boxing.

David

[knutinh]

New zoom mode: 4/3 -> 16/9 non-linear distortion - MediaPortal (http://forum.team-mediaportal.com/improvement-suggestions-46/new-zoom-mode-4-3-16-9-non-linear-distortion-21865/)

-k

[Ghitulescu]

I'd like to restore some old tape cam video to be seen on wide screen. I can't find a proper filter to smart resize, like some LCD does, the format, i.e. almost nothing in center and more on sides.

Any idea?

I have one TV that has several modi of displaying the 4:3 content, some of them distorted. I've seen a lot of other TVs that implement various ways to achieve this.

[wonkey_monkey]

I'm currently working on a filter that might of some help in this area - it's for correcting fisheye distortions but I think with the right parameters it might make a nice non-linear zoom.

David

[Alex_ander]

New zoom mode: 4/3 -> 16/9 non-linear distortion - MediaPortal (http://forum.team-mediaportal.com/improvement-suggestions-46/new-zoom-mode-4-3-16-9-non-linear-distortion-21865/)
-k
I wrote a primitive test script a week ago basing on exactly the same idea, but decided not to post it and even didn't test it then, since Didée mentioned an already existing function. Tested it just now, and it somehow worked.
It uses more rough screen division:
1)after stretching to target AR the central square is in original proportion (like it were cut out of 4:3 + pillarboxed)
2)left/right sides (1/4 of original width) divided in two zones and stretched to fill the screen using 2 different factors). So here it is without any optimization (of course, the numbers from chart, given in your linked thread, can be used after some expanding modification):

LanczosResize(720,576)#for a random 4:3 test source
a=crop(0,0,-688,0).LanczosResize(96,Last.Height)
b=crop(32,0,-640,0).LanczosResize(64,Last.Height)
c=crop(80,0,-80,0).LanczosResize(400,Last.Height)
d=crop(640,0,-32,0).LanczosResize(64,Last.Height)
e=crop(688,0,0,0).LanczosResize(96,Last.Height)
StackHorizontal(a,b,c,d,e)#720x576
LanczosResize(720,404)#or any 16:9 DAR for testing

If dividing width into distinct zones is visually acceptable, then it's easy to approximate a function (Gauss?) this way.