iPad Video Aspect Ratio problem

Discussion in 'iPad' started by Ninnibon, Apr 5, 2010.

  1. Ninnibon macrumors newbie

    Joined:
    Apr 5, 2010
    #1
    I have many movies that have been converted (remuxed) from mkv format to mp4 (m4v). For some reason, some of the movies have a squashed look when viewed in the Video app on the ipad. Some Movies that are 16:9 (720x480) display just fine in portrait/landscape, while others are squashed in both landscape/portrait?

    I also have problems with movies originally in 2.35:1. I don't mind seeing the black bars, as long as the aspect ratio is kept from the original file. I used the "loose" Anamorphic setting in Handbrake.

    Anyone else have similar problems or suggestions?

    Thanks! Love the iPad but want to watch my movies!
     
  2. GermanSuplex macrumors 6502a

    GermanSuplex

    Joined:
    Aug 26, 2009
    #2
    720x480 is not a 16:9 (widescreen) or 4:3 (fullscreen) ratio. However, many DVD's use 720x480 and will either squash the video in for fullscreen content or out for widescreen content. Your movies that are 720x480 and look correct are probably playing back anamorphically at 853x480 (widescreen) or 640x480 (fullscreen). The ones that are displaying improperly are probably playing back at 720x480 and not being stretched/sqaushed to what they're supposed to be. Basically, something in the mkv container was flagged so that the video played back in the correct aspect ratio. When you muxed from mkv to mp4, this flag was lost.

    If you have mpeg streamclip or Quicktime pro, you can change the display aspect ratio to 853x480 or 640x480 so that the video looks correct.
     
  3. Ninnibon thread starter macrumors newbie

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    Apr 5, 2010
    #3
    Thanks for the info. I figured something was lost in the remuxing process.

    I had been using mkvtools to remux from mkv to mp4, and then renamed it to m4v.

    Does changing the display aspect ration in QT pro involve transcoding?

    I'm trying to keep my movies in one digital format that is easily remuxable to various formats (for my PS3 5.1, iPhone, and iPad)
     
  4. GermanSuplex macrumors 6502a

    GermanSuplex

    Joined:
    Aug 26, 2009
    #4
    Nah, you don't have to transcode to change the aspect ratio. Otherwise you'd be better off encoding from the mkv. QuickTime pro is my favorite tool, but it costs.
     
  5. Ninnibon thread starter macrumors newbie

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    Apr 5, 2010
    #5
    So do I open the remuxed m4v in QT pro? Then where do I change the aspect ratio. And is there a formula to what ratio I change it to?

    Thanks!
     
  6. GermanSuplex macrumors 6502a

    GermanSuplex

    Joined:
    Aug 26, 2009
    #6
    Windows > Show Movie Properties > Highlight Video Track > Visual Settings > Edit the scaled size fields.

    If it's 16:9, you change it do 853x480. If it's 4:3, you change it to 640x480. If it's 2.39:1, I believe you set it to 853x352.
     
  7. Ninnibon thread starter macrumors newbie

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    Apr 5, 2010
    #7
    After I edit the aspect ratio, do I save or export in QT?
     
  8. GermanSuplex macrumors 6502a

    GermanSuplex

    Joined:
    Aug 26, 2009
    #8
    Save as a self-contained movie. It will be a .mov file. You can export to mp4, but I believe you lose chapter marks and stuff, but the video itself will be fine. You can use Drax or some Mac-equivelant to copy and past the chapters from the old file to the new one.

    If you leave the file as .mov, all tags will be retained, including meta info like chapter marks.
     
  9. Ninnibon thread starter macrumors newbie

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    Apr 5, 2010
    #9
    Thanks for the tips, it worked. Have you used mkvtools at all? There is a pixel aspect ratio adjustment that can be made on an mp4, although I am having trouble producing the same results that I got from QT Pro.

    QT pro worked well, expect I would rather not have to save another file (mov) to drag into iTunes.

    THanks again!
     
  10. Ninnibon thread starter macrumors newbie

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    Apr 5, 2010
    #10
    I spoke too soon....

    I realize now, but dragging a mov into iTunes doesn't help my iPad problem. Sync won't transfer the movie. Is there a way to go back to m4v with the adjusted aspect ratio?

    many you have any other suggestions from going from a handbrake mkv to itunes/ipad m4v with no transcoding? this seems like a pretty long workflow for.... not nearly as easy as my workflow for the ps3.
     

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