Looking for a torrent client

Discussion in 'Technical Discussion' started by Hivebrain, Apr 4, 2016.

  1. Hivebrain

    Hivebrain

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    Is there a torrent client that'll download the header of a compressed archive, and then let me use that information to selectively download files from within the archive? Same for MP4/MKV files, where I can select which video and audio tracks to download.

    It wouldn't work for solid 7Z/RAR archives, but it should in principle be possible for everything else.
     
  2. Sappharad

    Sappharad

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    I don't really think the principle is possible for MP4 and MKV files though.

    Torrents are broken into pieces of a fixed size (usually 512kb, but they can differ based on the size of the download and the tools used to create it) and video containers have audio and video tracks interleaved throughout the file. Although you can sometimes estimate where the audio and video data is inside a file, it's not always going to be easy to know especially if the data isn't constant bitrate. I don't know about MP4 and MKV specifically, but at least on MPEG2 containers the video is broken into blocks (similar to how a torrent is broken into pieces) and the only way to know the data type for each block is to read the header of that block. Since you need to download torrents in pieces, you basically need an entire piece just to know what type of data is contained in the blocks in that piece.

    The archive idea is really cool, sadly I don't have an answer to help.