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gmB2k1
31st January 2010, 14:58
I'm trying to backup my DVDs to my PC.
I re-encode it with the goal of having a high-quality copy.
I'm using x264, since it's the most sophisticated codec. For audio, I downmix to stereo and encode with neroAAC.
I'm using meGUI and put both audio and video in a mp4 container.

I hope, so far there are no flaws in this approach.

The problem is that:
DVD resolution is 720x576 (PAL).
Aspect ratio of the movie is for example 2,35:1.

To keep the aspect ratio in the end product, I'd have to resize my encoding to 720x306 (mod16 and cropping black borders aside).
This way I lose almost 50% of the vertical resolution or half of the details.

Another way of keeping the aspect ratio would be to resize horizontal resolution to 1354. This way, I'd keep all of the vertical resolution.
However, the resulting filesize would be much larger than with the original resolution of 720 for no additional detail. That would be a big waste of HDD space.

If I encode anamorphic in 720x576, I save all of the detail without wasting space. However, the aspect ratio would be heavily distorted, if I play it back in any software player.
VLC player has indeed the function of changing the aspect ratio of the video. One mode is 2,21:1. This is close to the often used 2,35:1, but not exactly. Furthermore, I'd restrict myself to watch only with the VLC player if I don't want a totally distorted aspect ratio.

This is really puzzling me. How can I have quality encodings in the right aspect ratio?

Thanks in advance!

Inspector.Gadget
31st January 2010, 17:12
However, the aspect ratio would be heavily distorted, if I play it back in any software player.

This should not be the case. I can't speak to VLC (though I would be really shocked if it didn't support anamorphic H.264-in-MP4), but I know for a fact that MPC-HC handles anamorphic H.264 content without issue.

manono
31st January 2010, 18:22
Yeah, for computer playback keep the 720x576 (or crop away the black bars and don't resize afterwards). I don't use the VLC player either, but most software players won't have any trouble at all with it. However, most hardware DVD/MPEG-4 players won't respect the PAR (if they'll even play it at all, which almost none will) and will give you that distorted look you mentioned.
Another way of keeping the aspect ratio would be to resize horizontal resolution to 1354.
I think you mean to say 1024. 576 x (16/9) = 1024.

stax76
31st January 2010, 19:19
My advice is encode anamorphic and throw anything away that don't support anamorphic playback.

gmB2k1
31st January 2010, 19:39
Hmm, it seems meGUI didn't set the aspect ratio flag correctly.
I played around with the settings and now it's working.

So, I'll definetly stick with anamorphic encoding.

Thanks!