musicXML: 1次测量中的2个语音

Question

我正在尝试创建一个包含两个声音的musicXML文件：

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE score-partwise PUBLIC
    "-//Recordare//DTD MusicXML 4.0 Partwise//EN"
    "http://www.musicxml.org/dtds/partwise.dtd">
<score-partwise version="4.0">
  <part-list>
    <score-part id="P1">
      <part-name>Music</part-name>
    </score-part>
  </part-list>
  <part id="P1">
    <measure number="1">
      <attributes>
        <divisions>1</divisions>
        <key>
          <fifths>1</fifths>
        </key>
        <time>
          <beats>4</beats>
          <beat-type>4</beat-type>
        </time>
        <clef>
          <sign>G</sign>
          <line>2</line>
        </clef>
      </attributes>
      <note>
        <voice>1</voice>
        <pitch>
          <step>F</step>
          <alter>1</alter>
          <octave>4</octave>
        </pitch>
        <duration>2</duration>
        <type>half</type>
      </note>
      <note>
        <pitch>
          <step>G</step>
          <alter>0</alter>
          <octave>4</octave>
        </pitch>
        <voice>1</voice>
        <duration>2</duration>
        <type>half</type>
      </note>
      <note>
        <pitch>
          <step>C</step>
          <alter>0</alter>
          <octave>4</octave>
        </pitch>
        <voice>2</voice>
        <duration>2</duration>
        <type>half</type>
      </note>
      <note>
        <pitch>
          <step>A</step>
          <alter>0</alter>
          <octave>3</octave>
        </pitch>
        <voice>2</voice>
        <duration>2</duration>
        <type>half</type>
      </note>
    </measure>
  </part>
</score-partwise>

对我来说似乎没问题:音符都是一样的。但当我使用musicxml2ly，然后使用lilypond时，第二个声音会转移到下一个测量值：

​

​

怎么啦？

Answer 1

musicxml中的每个音符都将时间指针向前移动，因此我的musicxml表示两个紧随其后的声音。为了使它们平行，我们需要在语音2的音符之前<backup>一个完整的小节，以将时间指针重置到小节的开始。

<note>
    <voice>1</voice>
    ...
</note>
<backup>
    <duration>4</duration>
</backup>
<note>
    <voice>2</voice>
    ...
</note>

https://www.w3.org/2021/06/musicxml40/musicxml-reference/elements/backup/