Video twice as high in Avidemux

[fbleach]

Hello!

When I open a VOB file with Avidemux, it is displayed twice the real height. (Avidemux's video/audio information says the image size is 352x576, aspect ratio: 32:15 (crazy!), frame rate: 25 fps. When the video is played in 100% zoom, VLC displays it as 750x576px.)

It is OK if I just cut a piece of the video and save it without re-encoding, as the resulting VOB file would play correctly in VLC. But if I try to convert it to AVI (Xvid), then the wrong proportion is also being encoded into AVI and displayed when played by VLC.

I thought that it could be related to interlacing, so I tried adding some deinterlacing filters, but the preview still show the wrong proportions and the same when the movie is actually encoded and saved.

Can anyone help me with this problem, please?

Thank you!

[setarip_old]

Hi!

1) What DVD (Title and Region number, please) is this .VOB from?

2) What software and procedures did you use to rip the .VOB?

3) What further conversion, if any, did you perform on the .VOB, that might have resulted in a resoltuion of 352x576?

[fbleach]

1) DVD Decrypter says the region is: 1; 2; 3; 4; 5; 6; 7; 8. :D The DVD was recorded with Philips DVD Recorder.

2) I used IsoBuster because the disc is unfinalized and won't open normally. (If I try to finalize it with the recorder, it returns an error.)

3) No further conversion — that's (one of) the VOB file IsoBuster extracted.

[setarip_old]

Last question - Did you set the recorder for 768x576 or 352x576?

[fbleach]

Erm… I'm not sure what question is that. I think that there is not such option for that recorder. It is only possible to select NTSC or PAL (we have PAL) and the quality (1, 2, or 4h per disc).

[Guest]

Well then what quality did you select? If you select a lower quality, then it can be saved at width 352 and then resized at *playback time*. That gets you more time for your recordings at the expense of quality. Try it at the highest quality setting. What happens?

[LoRd_MuldeR]

I guess your video was encoded anamorphic! It think that is S-VCD resolution. Maybe the recorder used that in order to make more video fit on the DVD-R.

Every player would stretch the video from it's resolution of 352x576 to the correct display aspect ratio of 4:3, so the video will look "normal" during playback. But that doesn't change the fact that the resolution of the video is *not* 4:3 at all. Avidemux shows the video "as-is" without applying any DAR/PAR (as most video encoders would and do). When editing the video, you want to see the "original" video and a "stretched" version, right? So you have two options here: You can either keep the video anamorphic (don't resize and set the correct PAR in the encoder - the video will look "normal" in a player) or you can "restore" a PAR of 1:1 via resizing (e.g. you can resize to 640x480 or 320x240).

[fbleach]

Thank you all for replies!

neuron2, I cannot test it now as the recorder is not at my house but the thing is that I need to deal with already recorded material.

LoRd_MuldeR, thanks for the explanation. I think I'll go with resizing. But how could I set that PAR in Avidemux if I wanted? And how do you explain the aspect ratio Avidemux display: 32:15?

[LoRd_MuldeR]

LoRd_MuldeR, thanks for the explanation. I think I'll go with resizing. But how could I set that PAR in Avidemux if I wanted? And how do you explain the aspect ratio Avidemux display: 32:15?

1. You set the PAR in the individual Video Encoder configuration dialog. (See screenshot (http://img443.imageshack.us/my.php?image=avidemuxparsk0.png))
2. I think 32:15 is not the DAR (Display Aspect Ratio), but the PAR (Pixel Aspect Ratio).

If you apply a PAR of 32:15 to a resolution of 352x576 then you get 750x576, which has a DAR of ~4:3.

Horizontal "stretching factor" is: 32/15 = 2,133
This results in a horizontal resolution of: 352 * 2,133 = 750,933
So final resolution is: 750x576

You end up with the same resolution that VLC uses according to your initial post :)

[fbleach]

Thanks for the explanation. I clicked on XviD encoding options and there if I checked "Pixel Aspect Ratio", it changed to 32:15. Now it makes sense. :)