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Author Topic: Manual adjustment of Aspect Ratio  (Read 4956 times)

whatlarks

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Manual adjustment of Aspect Ratio
« on: October 02, 2016, 12:47:08 pm »

I can't seem to find any way to manually change the aspect ratio on a video. On the Windows version there is an option on the right button submenu. Is there any way to achieve this on the Mac version (currently on 21.0.80).

Thanks,
Ian
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blgentry

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Re: Manual adjustment of Aspect Ratio
« Reply #1 on: October 02, 2016, 03:11:41 pm »

I don't think there's any way to directly adjust that.  Each video file has a field [Playback info], which contains some "magic strings".  By copying these from one file to another, you can make one file play back like another.  But this includes everything:  The audio stream, subtitles, etc.  YOu might be able to copy parts of it over; I'm not 100% sure.

What are you trying to do?  I.E. why do you want to alter the aspect ratio?

Brian.
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whatlarks

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Re: Manual adjustment of Aspect Ratio
« Reply #2 on: October 03, 2016, 01:11:17 pm »

Thanks for the reply Brian. I have a number of recordings from my ageing Panasonic DVD/HDD Video recorder on DVD-Rs. I have been transferring some of these to my Windows computer, which is used as my JRiver Media Center server, with a view to playing them on my not-so-smart Panasonic TV using my MacBook Pro. These TV recordings are 16:9 but the Panasonic has set the aspect ratio on the DVDs to 4:3.

This is no problem when played on my Windows computer because Media Center has an option to manual alter the aspect ratio. Sadly, this feature does not appear to have made it across to the Mac version.

Thanks,
Ian
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blgentry

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Re: Manual adjustment of Aspect Ratio
« Reply #3 on: October 03, 2016, 02:41:38 pm »

So, do you end up with a doubled boxed picture?  Black bars on the sides *and* black bars on the top and bottom?

MC can't do anything with these files at the moment as far as I know.  Because to "fix" this, the picture needs to be zoomed.  VLC can do this with it's Crop menu options.

AVIDemux *might* be able to resize/reaspect/crop these for you, but I haven't tried it.  Note that any crop/reaspecting with an external tool (like avidemux) necessarily alters the video permanently and will re-save it with a codec, which might also lose some video quality.

Brian.
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whatlarks

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Re: Manual adjustment of Aspect Ratio
« Reply #4 on: October 06, 2016, 07:06:52 am »

No, I think the best way I can describe it is 16:9 squashed horizontally into 4:3. So height is fine but width is squashed.  Changing the settings on Video/Advanced/Aspect Ratio Correction or Aspect Ratio Mode has no effect. Hope this makes sense.

Thanks,
Ian
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blgentry

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Re: Manual adjustment of Aspect Ratio
« Reply #5 on: October 06, 2016, 07:30:47 am »

Oh interesting.  So they are simply Anamorphically squeezed:  A 16x9 frame forced to fit into a 4x3 frame by horizontally resizing.  MC (and all DVD players) know now to unsqueeze this into a proper 16x9 frame.

I've just done 5 minutes of research and found quite a few forum postings about people with this same problem.  I was hoping to find a software fix that would set the 16x9 flag for aspect ratio in your files. I'm not even sure what kind of files the Panasonic produces.  Regular DVD VOB structures?

I would *guess* that converting those to MKV, and then using an MKV tool would allow you to change the aspect ratio.  You'd have to try it to be sure.

Maybe one of the dedicated video forums might be able to point you in the right direction to process these in some way.

I'm guessing MC can't do this for you, but I could be wrong...

Good luck!

Brian.
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