Amount of encodes from source?

Discussion in 'Apple TV and Home Theater' started by Mr Dobey, Mar 30, 2013.

  1. macrumors 6502

    Joined:
    Aug 8, 2008
    #1
    I was thinking about the quality of iTunes and started wondering at what point in the production chain is the iTunes video compressed.

    So for a movie is the iTunes 1080p video compressed straight from the master studio file or do they get lazy and take the Blu-Ray file and compress it again into a lower bitrate version?

    This especially came to mind since a lot of people here are taking Blu-Rays and re-encoding them to lower bitrates to play on their Apple TV's, making the video encoded twice.
     
  2. macrumors regular

    Joined:
    Mar 21, 2010
    #2
    Apple does not encode their content from blu rays. They're a bit more professional (even if an encode with a blu ray looks better what Apple provides). I'm not exactly sure but I believe they get their source file from the studios and Apple does what they do.
     
  3. Moderator

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    Staff Member

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    #3
    Apple used to encode from 220 Mb/s ProRes 422 HQ, but I've heard that that is no longer the case. It's probably still a good baseline though...
     
  4. macrumors 65816

    Joined:
    Sep 16, 2007
    #4
    I don't think Apple is encoding anything. They probably have a deal with the content providers (the film studios), requesting them to provide Apple with an iTunes compatible encode. And these studios likely use their master source. I doubt this master source file ever leaves the film studio, for security reasons. I could be wrong though...
     
  5. thread starter macrumors 6502

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    Aug 8, 2008
    #5
    Thank you guys.

    I had the feeling Apple got a pre compressed video file according to the iTunes standards considering this is how they manage their music files.
     
  6. macrumors 6502

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    Apr 5, 2012
    #6
    There's a pdf file if you search online that has all the details, but this is what I've read as well.

    ----------

    Apple hires outside encoding companies that encode the video from the studios and then send it to apple for final sale.
     
  7. macrumors 68000

    Joined:
    May 6, 2004
    #7
    Woooo

    What is pre compressed? Take the BluRay then compress it? Take the 4k or 2k DI to 1080p, that's compressed too. I think we'd have define what compression is tolerable.

    1 hour of miniDV at "5:1" compression at Standard Def is 12-13GB

    HDTV is compressed.

    A CD is compressed too, so most iTunes music is a compression of a compression. But so was napster and almost every mp3 ever made.

    Where an iTunes video is sourced and compressed is speculation until someone in the supply chain is willing to go on record. Maybe many of them won't bc they work for companies taking the lazy easy way? Who knows?

    Just don't expect an easy answer bc some film companies will spend a little more for a higher quality product than others. Just like any industry.


    My thinking would be, how do they get 80-90% of the quality at 20% the size of a BluRay. Or more likely, if the film has a good story, why am I analyzing the compression.
    People get too caught up in the tech and numbers, rather than enjoying the story.
     
  8. macrumors 6502

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    Apr 5, 2012
    #8
    As was said before, Apple uses 220 Mb/s ProRes 422 HQ.
     
  9. macrumors 601

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    May 21, 2009
    #9
    So somebody sits there at apple and encode every movie


    That's gotta be a fun job
     
  10. Moderator

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    Staff Member

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    #10
    It's automated. It'll be something like "drop folder of movies onto droplet, wait however long, grab output files".
     
  11. macrumors 65816

    Joined:
    Sep 16, 2007
    #11
    At least someone needs to check the quality of the encode, making sure no artifacts in the video or audio.

    For example, producing an AAC stereo track as a downmix from a multichannel audio source should require some individual handling, if they care about things like dynamic range and dialnorm. These are things that cannot be automated with tools like Handbrake.
     
  12. Moderator

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    Staff Member

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    #12
    Needs to, but doesn't. I've stopped buying from iTunes now with the amount of absolute rubbish on there.
     
  13. macrumors 68000

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    May 6, 2004
    #13
    I've got a friend that has shows on HBO and trailers on YouTube, so I'll ask about the compression process.
     
  14. thread starter macrumors 6502

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    Aug 8, 2008
    #14
    Thank You!
     

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