Restoring Original Aspect Ratio 2.35:1

[moviebuff2]

Hi everyone:

I have 2 AVI files which came from 2.35:1 movies. For some unknown reasons, when convert to AVI, the original 2.35:1 aspect ratio was changed. One AVI has 2.50:1 ratio and a size of 640 x 256; the other, 2.400:1 and 576 x 240.

I would like to restore the 2.35:1 for these AVIs. Is it possible? If yes, what do I have to use? Will VirtualDubMod's resize filter do the job?

Thanks

[guns1inger]

Unfortunately, unless the image is distorted, you can't return them to 2.35:1 without doing further damage. To have altered the aspect ratio in them manner that has been done here, some of the image has already been cropped. To return the aspect ratio you will have to either crop more, or just add black bars to the top and bottom. For example, the 640 x 256 image would have to be further cropped to 602 x 256 to get 2.35:1. The 576 x 240 would have to be further cropped to 564 x 240.

The perils of downloading.

[manono]

To change the AR means reencoding and further image degradation. Most real widescreen DVDs aren't 2.35:1 these days anyway, but between 2.40-2.45:1 (not talking about the 1.78:1/1.85:1 ones). Assuming the encoder knew what he was doing (a big assumption, I'll grant you). he cropped and resized to keep to Mod16 resizing with low Aspect Error. Therefore the title of this thread in misleading, at best. Sure, you could make them both 640x272, but with no guarantee that you'll be lowering the Aspect Error, and the distinct likelihood that you'll be increasing the Aspect Error. Leave them alone.

[jagabo]

Are you sure they aren't the correct aspect ratio? Many applications (fitcd) add black borders to make the frame an even multiple of 16 (which both your files are). So the actual picture within the frame may be the right aspect ratio.

If your files are Divx, Xvid or some other MPEG4 codec, you can use MPEG4Modifier to change the picture aspect ratio for playback. This doesn't involve reencoding, it just changes the aspect ratio flag. Most software players will use the setting, most set-top players will not.

In any case, the small difference is hardly worth reencoding. Your TV probably has a larger aspect ratio error!

[moviebuff2]

Hi everyone:

Thanks for your inputs.

Yes, the original aspect ratio is 2.35:1 because 1) the legitimate DVD cover says so 2) with the current ratios (2.50:1 & 2.40:1), the faces of familiar actors/actresses look unusually chubby.

I just changed one AVI size from 576 x 240 (2.40:1) to 576 x 246 (2.34:1), using VirtualDubMod resize filter. When I played both files (original & modified) on my Philips DVP642, they were displayed exactly the same on my TV monitor. To make sure that my eyes were not deceiving me, I even used some color tape to mark the height of the video display.

For some reasons that I don't know, the Philips just ignored the changes in size.

I will try with different size settings to see if any of them would help.

Cheers

[jagabo]

Yes, the original aspect ratio is 2.35:1 because 1) the legitimate DVD cover says so 2) with the current ratios (2.50:1 & 2.40:1), the faces of familiar actors/actresses look unusually chubby.

Then your aspect ratio is off by way more than 2.4 or 2.5 vs 2.35. Find something in the film that you know should be round (a sphere, a tire viewed from the side, etc) or square and resize accordingly.

[moviebuff2]

Hi jagabo:

DivXToDVD & VirtualDubMod both told me the sizes are 640 x 256 and 576 x 240. DivXToDVD was even more specific with the aspect ratios 2.50:1 & 2.40:1.

I guess I have "sensitive" eyes. Just a little of chubbiness is all it takes to make me notice it.

I just downloaded the software Mpeg4Modifier. I will let you know what happens. Thank you for telling me about this software.

Cheers.

[jagabo]

Those programs are simply telling you the aspect ratio of the frame (640/256 = 2.5, 576/240 = 2.4). This has nothing to do with the aspect ratio of the picture encoded within that frame (the display aspect ratio).

MPEG4Modifier lets you specify a display aspect ratio but I'm pretty sure the DVP642 will pay no attention to it.

Since you have no idea what the original ripper did to the picture you can only restore the aspect ratio by eyeballing it. Find something you know should be perfectly round (and near the center of the picture) on the TV, measure the width and height, then resize to video to compensate. My guess is that reducing the width of your video by 10 to 12 percent will come close to fixing aspect ratio.

[manono]

Yes, the original aspect ratio is 2.35:1 2) with the current ratios (2.50:1 & 2.40:1), the faces of familiar actors/actresses look unusually chubby.

Sheer and utter nonsense. You have no idea what you're saying. I could crop and resize a DVD so it's 8:1 and it will have perfect AR, and the faces won't look chubby. Take a DVD of a so-called 2.35:1 movie sometime, crop away the black, resize it, and check the AR.

...because the legitimate DVD cover says so

Give me a break.

[guns1inger]

DivxtoDVD expects all avis to have a DAR of 1:1.

The faces would only change if, in addition to cropping, the original encoder also resized the image incorrectly. I suspect it is either something the Philips is doing, or your TV's calibration that is giving this appearance.

[moviebuff2]

Thank you jagabo & guns1inger:

I used MPEG4Modifier and fixed the problem. The picture is displayed properly when I played it with the Philips. I guess the Philips likes what MPEG4Modifier encoded.

Thank you for making me believe that help and civility have not become "endangered spiecies" in this age of the Internet where many simply assume a pseudo or two and start behaving behind that pseudo like some wild animal.

Cheers

[jagabo]

Glad to hear MPEG4Modifier worked. I'll have to remember that!

[moviebuff2]

Hi jagabo:

All I did was open MPEG4Modifier, load the AVI, let MPEG4Modifier analyze the file, chose display AR as 2.35:1, save the new AVI to a folder.

After that, I used DivXToDVD to convert the new AVI to VOB. I selected automatic for Aspect and NTSC 29.97 fps for Standard.

Finally, I used Nero to burn onto a DVD. Using the Philip DVP642 to play the new DVD, the displayed video looked much better with a little more height (same width). The faces were no longer chubby like in the original video.

Thanks again.

[jagabo]

Oh, I thought you were playing the Divx file directly since you have a Divx/DVD player.

I'm not surprised the aspect ratio was correct when converting to MPEG for DVD. The Xvid codec will give the MPEG encoder the correct aspect ratio.

[moviebuff2]

Hi:

When I converted the original (unmodified) AVI to VOB, and played the video with my stand-alone Philips, the pictures were bad. The faces were chubby (not a lot, but noticeable) and also people looked somewhat shorter.

Anyway, I'm satisfied with the modified version.

[jagabo]

Just to complete the discussion regarding the Philips DVP-642:

I had a chance to try a 640x480 Xvid AVI file marked for 16:9 DAR with MPEG4Modifier on a Philips DVP-642 today. The player ignored the 16:9 DAR flag and displayed it as square pixel (4:3). Windows Media Player and Media Player Classic displayed the same file as 16:9 DAR.

[garryheather]

1) the legitimate DVD cover says so

I'd go out and buy that, then... if you're putting this much effort into saving a hack-job it's probably worth the money.