Convert AVI file from 16x9 to 4x3 aspect ratio?

[tsurikov]

Hi all,

I'm hoping for a bit of insight... A friend shot some DV footage in 16x9 format. I'd like to use the resulting AVI file (6 GB) in my 4x3 video projects. However, I cannot figure out how to convert/resize the file. I normally use TMPGEnc or VirtualDub for my conversion needs. However, both tools open the file in the unattractive mode where everything looks squeezed from left to right. In other words, they don't seem to recognize the wider aspect ratio. And if I ignore this and proceed anyway, I get a resulting 4x3 file with the squeezed appearance.

The only program I've found that recognizes the 16x9 format is Windows Media Player... and I can't use it to convert the file...!

I have no problem with letterboxing and/or cropping a fixed 4x3 area from the 16x9 footage (pan&scan not necessary)... I just would like to know how to do this without producing squeezed images!

Thanks for reading and any insight!

(PS: Yes, I've dug through the posts here on VideoHelp.com... but all the ones I've seen talk about going "the other way" - everyone seems to want to go from 4x3 to 16x9...)

[Alex_ander]

The way you see it (as I can understand you see it 4:3 without borders) means the application treats it like a square-pixeled avi file. It doesn't matter when you have to resize it anyway. If you want to use it in a 4:3 .avi project you'll have to make it letterboxed by adding borders at resizing. E.g. in VirtualDub in resize filter you can check 'expand frame and letterbox image' and independently set frame size (4:3) and your 16:9 image size ('new width/new height') inside the frame.
If you plan to further encode it to DVD, then resize settings in VDub should be 720x(432+72+72) - with (72+72) borders, taking into account PAL pixel ratio (12:11). Then frame size is 720x576, image is 720x432 (unlike .avi target case, it shouldn't be 16:9 here).

[joy]

try read this: https://forum.videohelp.com/viewtopic.php?t=298712&highlight=

[JohnnyMalaria]

Try running the DV file through our Enosoft DV Processor (it's free to try - you need XP and a CPU with SSE2).

It will do the aspect ratio conversion in real-time. It recognizes 16:9-tagged files, resizes them to look correct on 4:3 displays. The output is 4:3-tagged DV. All other attributes of the DV file are maintained (recording date, time etc).

For example, here is a frame from a 16:9 DV video (deliberately chosen to show the interlacing):



and here is the same thing after processing:



The fields are preserved correctly.

It works on AVI files and also on live DV during capture.

The current version is 0.17 and does not write to Type-2 DV AVI files. 0.18 will be available in the next few days and does support both Type-1 and Type-2 (plus a lot of other improvements).

[jagabo]

In TMPGEnc go to Setting -> Advanced and set Source Aspect Ratio to 16:9. If you want the 16:9 image letterboxed inside a 4:3 frame (ie with black bars top and bottom) set Video Arrange Method to Center (Keep Aspect Ratio). If you want to crop the edges so there are no black borders use No Margin (Keep Aspect Ratio) instead. Make sure Video Source Type and Field Order are set properly for your source.

To do the same In VirtualDub use the Resize Filter. To get a letterboxed result Resize to 720x360 and enable Enlarge Frame and Letterbox Image to enlarge the frame to 720x480. If your source is interlaced be sure to select the Interlaced option. If you want to crop the image down to 4:3 resize to 720x480 then go back to the main Filters dialog hilite the Resize filter and press the Cropping button. Crop 90 pixels off the left and right borders. (When cropping is applied to a VirtualDub filter, the cropping takes place before the filter is applied. So what you are doing is cropping the frame then resizing what's left back up to 720x480.)

[tsurikov]

Thank you all for your helpful responses! Jagabo, I used your method (since I had the tools) and it worked flawlessly. I would've never found those settings without your pointers.

[jagabo]

Glad to help out.

TMPGEnc uses a bilinear resizing filter which isn't so good. Generally, resizing with VirtualDub's or AVISynth's Lanczos (reducing) or Bicubic (enlarging) filters will give better results.