ScratchML draft spec v3

scratchml.xml

<sml>
  <!--

  # SCRATCH MARKUP LANGUAGE, WORKING DRAFT
  http://scratchml.com
  
  * version -- minor versions for small changes, major for incompatibilities
  * info -- general file metadata: author info, client info etc.
  * turntable - hardware metadata
  * mixer -- hardware metadata
  * audio -- info + raw data for audio recording, or links to external files
  * transcription -- turntable markup (TTM)-style notation of fader cuts & record movements
  * performance -- actual recorded fader/hand event data
  
  most fields are optional. you can have a performance without a transcription, and vice versa.
  no xml attributes are used, to aid in json/xml conversion.
  
  all times are in milliseconds.
  
  todo: pitch, per-channel volume, fader contour

  -->

  <version>
    <major>0</major>
    <minor>3</minor>
  </version>
  
  <info>
    <client>Cutcapture 9000 version 1.1</client>  <!-- sml generator -->
    <author>
      <name>Qbert</name>
      <url>http://www.djqbert.com</url>
      <location>
        <description>San Francisco, CA</description>
        <latlon>32.44, 22.34</latlon>
      </location>
    </author>
    <description>Crab/flare combo, 1998</description> <!-- title/commentary -->
    <tags>crab, flare, old</tags> <!-- comma-separated keywords -->
    <created>2012-07-17T09:24:17Z</created> <!-- ISO-8601 -->
    <url>http://scratchml.com/data/340923</url> <!-- added on upload if not present -->
  </info>

  <audio>
    <sample>
      <filename>samples/fresh.wav</filename> <!-- can be a local file, or a URL -->
      <description></description> <!-- artist + title, break, or sample name -->
      <!-- the following are used when working with multiple samples over a set -->
      <deck>left</deck> <!-- which turntable -->
      <start></start> <!-- when it starts during the performance -->
      <stop></stop> <!-- when it stops during the performance -->
    </sample>
  </audio>
  
  <!-- this is the raw version -->
  <performance>
    <turntable>
      <!-- 
        record movement is stored as a list of floats.
        a 15 second performance at 375 Hz samplerate should be ~85KB
        a record spinning at 33 1/3 rpm takes 1800 ms to do one rotation
        so if you store a maximum of two decimal points, that's 500 samples per degree
        which should be more than enough precision.
      -->
      <deck>left</deck>
      <samplerate>375</samplerate> <!-- in samples per second. every 128 samples @ 48KHz = 375 samples/second -->
      <data><p>1000.02</p><p>1010.32</p><p>1020.34</p><p>1030.23</p></data>
    </turntable>
    <mixer>
      <fader>
        <hamster>true</hamster>
        <data>
          <!--
            0 means the fader is completely to the left
            1 means the fader is completely to the right
            normally 0 means that you can hear the left turntable
            when hamster is true, 0 means you can hear the right turntable
          -->
          <event>
            <time>0</time>
            <position>0</position>
          </event>
          <event>
            <time>1736</time>
            <position>.5</position>
          </event>
          <event>
            <time>2362</time>
            <position>1</position>
          </event>
          <event>
            <time>3034</time>
            <position>.5</position>
          </event>
        </data>
      </fader>
    </mixer>
  </performance>
  
  <!-- this is transcribed version -->
  <transcription>
    <turntable>
      <deck>left</deck>
      <!-- there are multiple labelled scratches -->
      <scratch>
        <name>flare</name>
        <curve> <!-- curve: baby, scribble, etc (derivative = 0) -->
          <time>0</time>
          <position>0</position>
        </curve>
        <line> <!-- lines: transformer, chirps (derivative = (next-cur)/length) -->
          <time>1000</time>
          <position>1000</position>
        </curve>
      </scratch>
    </turntable>
    <mixer>
      <fader>
        <!-- move means the fader is cutting in or out -->
        <move>
          <time>1000</time>
          <position>center</position>
        </move>
        <!-- a click is a very short, temporary move -->
        <click>
          <time>1500</time>
          <position>right</position>
        </click>
        <!-- a crab is a sequence of evenly spaced clicks -->
        <crab>
          <position>right</position>
          <clicks>3</clicks>
          <time>
            <start>3000</start>
            <end>3400</end>
          </time>
        </crab>
      </fader>
    </mixer>
  </transcription>
</scratch>