Problems with a Divx and its Aspect Ratio

[Talayero]

Hello,

I have a Divx with this AR: 528 x 288 (1:83:1.) I don't understand how it's been compress, because all figures are seen small and fat, just the opposite to a 16:9 aspect ratio when you see it 4:3, that shows tall and thin figures.

The thing is I can't see it properly on my TV not even if I change the AR display of the player or of the TV.
I tried every possible combination and in the end I reencoded the file resizing it to 384 x 288. Now I can see it right but I think there must be a better solution.
I used mpeg4 modifier tryng to change the AR flag or so, but it didn't work.

My questions are:

1.-The person who created that divx, did it properly?

2.-Is there a way to fix it without reencoding/resizing?

3.-Does that resizing I made (384 x 288) implies a loss of quality? (I suposse yes, from 528 to 384 there's a difference)

Thanks in advance.

[guns1inger]

Load it into Virtualdub, the right-click o the image and change the presentation AR. Yes, you have probably lost quality reducing it that far. How did you resize it ?
Can you post a frame grab to show the distortion ?

[Talayero]

Thanks for answering.

I have resized IT using the divx configuration in virtualdubmod: Enable resize. Bicubic Normal.

This is a frame:


I can see it right in the PC if a change the AR in virtualdub, as you said, or in any software player, but not on my TV.

[Talayero]

Sorry for such a big image, but I didn't know well how to grab it.

That distorted black and white picture is what I see if I let the original aspect in the software players.
I see it well on TV after resizing to 384 x 288, but that may imply a lost of quality.

[manono]

Hi-

1. No, judging from the picture, he resized it as if was coming from a 16:9 DVD, rather than from a 4:3 DVD as he should have. He most likely used the default 16:9 DAR in Gordian Knot.

2. You can change the AR in many software players, or in ffdshow, but most standalone DVD/MPEG-4 players don't have that ability.

3. All reencoding loses quality. I think you probably lost more than necessary because you downsized it. I would have made it 528x384, as the original encoder should have.

[Talayero]

Thanks,
I'll do a new resizing using what you propose: 528 x 384.
I did 384 x 284, because of my inexperience. I thought if the original divx hat 284 vertical resolution I couldn't resize it to a bigger figure.

I didn't know that all reencoding loses quality. Now and then I reencode avis from divx3 low motion to divx 5, because of incompatibilty with my standalone, and I thought that the avi won quality, or at least it didn't lose any.

[simps]

Is your .avi playing on correct aspect ratio on 1:1, 4:3 or 16:9 at all?

You should open it in virtualdub, and then check it by right clicking the output frame, and then changing the aspect ratios.

since its a .avi, it probably should play right on a 1:1 AR.

Let me know if it does first;

[]´
Simps

[Talayero]

No, there's no change checking 1:1 AR in virtualdub, the same fat and small figures.
The only way in virtualdub is choosing 4:3 frame ratio.

[simps]

Ok, so if the 528x288 movie looks right @ 4:3 AR in virtualdub, then do this

Resize the original 528x288 to 720x392
Then add 44 lines of black boarders on bottom and top, to get the full d1 720x480 resolution.

Then just encode @ 4:3 ntsc DVD and you are done.

Hope it helps.

Here is the simple avisynth script you need to do it:

AVISource("c:\yourmovie.avi")
Lanczos4Resize(720,392)
AddBorders(0,44,0,44)

Install the latest avisynth, save the above script on a "file.avs" file.
Then open this "file.avs" file on your encoder, like CCE or TMPGENC, and you are done.

[]'
Simps

[Talayero]

Thanks.

The thing is I want to keep it in divx format to see it in a standalone that plays mpeg4. I used to convert divx to dvd before I bought that player.

Taking that into account, which is the best resizing in order not to lose to much quality? 528 x 384, as manono said?