How to get Bitrate from AT3 files?

Discussion in 'PSP - Hacking & Homebrew' started by omarrrio, Jul 31, 2015.

  1. omarrrio
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    omarrrio GBAtemp Advanced Fan

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    As the title says, also are there any spreadsheet or wiki talking about the header of ATRAC3 and defining each WORD in it ?

    Thank you​
     
  2. jurassicplayer

    jurassicplayer Completionist Themer

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    There isn't really a spreadsheet or wiki for the ATRAC3 header that I have ever found, so I don't know all the WORDs.

    I made a new wiki page on the gbatemp wiki with the stuff that I found out and some of the stuff I glanced at, but do take it with great heaping piles of salt because before I started looking at AT3 stuffs (spent a couple days looking at stuffs for at3/pmf), I didn't know what little endian meant.

    I also don't know C++ so I can't fully make sense of where PPSSPP has their stuff regarding the header.

    If you happen to figure out or know other bits of the header, feel free to add it in or tell me. Unfortunately, it probably won't completely help you find the bitrate unless you want to do some really funky stuff and just compare unknown bitrate chunks to bitrate chunks you at least know are certain bitrates (since AT3 only uses certain bitrates IIRC).

    http://wiki.gbatemp.net/wiki/Atrac3plus
     
  3. omarrrio
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    omarrrio GBAtemp Advanced Fan

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    Thank you, i actually made a lot of progress, i shall update that wiki sheet with the known bitrate values so far.
     
  4. jurassicplayer

    jurassicplayer Completionist Themer

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    I've added some new stuff about the unknowns of the bitrate thanks to the multimedia.cx wiki while comparing your values to what they say are valid bitrates (the bitrates for at3+ are fixed).

    The major unknown stuff left is just anything in smpl and the huge chunk of supposedly unchanging stuff between the bitrate stuff.
     
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  5. omarrrio
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    omarrrio GBAtemp Advanced Fan

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    That is great :D thank you