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  1. 19th Feb 2020 18:16 #31
    Sotee
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    Originally Posted by poisondeathray View Post
    many blurays use open GOP
    How can you determine whether it is open or closed GOP when this information is missing from MediaInfo?
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  2. 19th Feb 2020 18:29 #32
    poisondeathray
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    Originally Posted by Sotee View Post
    Originally Posted by poisondeathray View Post
    many blurays use open GOP
    How can you determine whether it is open or closed GOP when this information is missing from MediaInfo?
    A stream analyzer

    I think ffprobe can too
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  3. 19th Feb 2020 18:46 #33
    Sotee
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    I am searching with google for answers/commands about that, but I can't find any to check easily.

    For each I-frame in the sequence, search packets after it and note AVPacket.pos and AVPacket.pts. If B(pos) > I(pos) but B(pts) < I(pts), you have open GOP, else closed GOP.

    If you want to be more precise, find some way to export the POC from the h264 parser, which is directly proportional to the timestamp.

    The official way to confirm that is parse the reference list from the headers and make sure the I is in the reflist for the B.
    See more in a separate thread for this.
    Last edited by Sotee; 20th Feb 2020 at 13:08.
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