我正在尝试为每个音符获取如下信息表：
Pitch - Octave - AbsoluteStart - Duration - Tied - MeterOfMeasure - Quarterlength
对于流中的每个音符（可以包含声音等）。 是否有一种简单的方法来迭代所有笔记，所以我可以通过一个来调用属性？
from music21 import *
song = converter.parse('test.xml')
我一直在努力：
song.show('t')
问题在于缺少关键信息（持续时间等）。
ps：理想情况下，我可以对流进行预处理，以便将Ties视为完整音符持续时间。我相信Stream.stripTies可以实现这一点。
我正在测试的musicXML文件是：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE score-partwise PUBLIC "-//Recordare//DTD MusicXML 3.0 Partwise//EN" "http://www.musicxml.org/dtds/partwise.dtd">
<score-partwise>
<identification>
<creator type="composer">Brennan Becker</creator>
<encoding>
<software>MuseScore 2.0.3.1</software>
<encoding-date>2017-07-13</encoding-date>
<supports element="accidental" type="yes"/>
<supports element="beam" type="yes"/>
<supports element="print" attribute="new-page" type="yes" value="yes"/>
<supports element="print" attribute="new-system" type="yes" value="yes"/>
<supports element="stem" type="yes"/>
</encoding>
<source>http://musescore.com/score/2383771</source>
</identification>
<defaults>
<scaling>
<millimeters>7.05556</millimeters>
<tenths>40</tenths>
</scaling>
<page-layout>
<page-height>1584</page-height>
<page-width>1224</page-width>
<page-margins type="even">
<left-margin>56.6929</left-margin>
<right-margin>56.6929</right-margin>
<top-margin>56.6929</top-margin>
<bottom-margin>113.386</bottom-margin>
</page-margins>
<page-margins type="odd">
<left-margin>56.6929</left-margin>
<right-margin>56.6929</right-margin>
<top-margin>56.6929</top-margin>
<bottom-margin>113.386</bottom-margin>
</page-margins>
</page-layout>
<word-font font-family="FreeSerif" font-size="10"/>
<lyric-font font-family="FreeSerif" font-size="11"/>
</defaults>
<credit page="1">
<credit-words default-x="1167.31" default-y="1402.31" justify="right" valign="bottom" font-size="12">Brennan Becker</credit-words>
</credit>
<credit page="1">
<credit-words default-x="612" default-y="1527.31" justify="center" valign="top" font-size="48">Test</credit-words>
</credit>
<part-list>
<score-part id="P1">
<part-name>Piano</part-name>
<part-abbreviation>Pno.</part-abbreviation>
<score-instrument id="P1-I1">
<instrument-name>Piano</instrument-name>
</score-instrument>
<midi-device id="P1-I1" port="1"></midi-device>
<midi-instrument id="P1-I1">
<midi-channel>1</midi-channel>
<midi-program>1</midi-program>
<volume>78.7402</volume>
<pan>0</pan>
</midi-instrument>
</score-part>
</part-list>
<part id="P1">
<measure number="1" width="641.30">
<print>
<system-layout>
<system-margins>
<left-margin>21.00</left-margin>
<right-margin>0.00</right-margin>
</system-margins>
<top-system-distance>195.00</top-system-distance>
</system-layout>
<staff-layout number="2">
<staff-distance>65.00</staff-distance>
</staff-layout>
</print>
<attributes>
<divisions>4</divisions>
<key>
<fifths>1</fifths>
</key>
<time>
<beats>2</beats>
<beat-type>4</beat-type>
</time>
<staves>2</staves>
<clef number="1">
<sign>G</sign>
<line>2</line>
</clef>
<clef number="2">
<sign>F</sign>
<line>4</line>
</clef>
</attributes>
<direction placement="above">
<direction-type>
<metronome parentheses="no">
<beat-unit>quarter</beat-unit>
<per-minute>100</per-minute>
</metronome>
</direction-type>
<staff>1</staff>
<sound tempo="100"/>
</direction>
<note>
<rest/>
<duration>8</duration>
<voice>1</voice>
<staff>1</staff>
</note>
<backup>
<duration>8</duration>
</backup>
<direction placement="below">
<direction-type>
<pedal type="start" line="yes"/>
</direction-type>
<staff>2</staff>
</direction>
<note default-x="88.37" default-y="-130.00">
<pitch>
<step>C</step>
<octave>3</octave>
</pitch>
<duration>1</duration>
<voice>5</voice>
<type>16th</type>
<stem>down</stem>
<staff>2</staff>
<beam number="1">begin</beam>
<beam number="2">begin</beam>
</note>
<note default-x="174.47" default-y="-125.00">
<pitch>
<step>D</step>
<octave>3</octave>
</pitch>
<duration>1</duration>
<voice>5</voice>
<type>16th</type>
<stem>down</stem>
<staff>2</staff>
<beam number="1">continue</beam>
<beam number="2">continue</beam>
</note>
<note default-x="260.56" default-y="-120.00">
<pitch>
<step>E</step>
<octave>3</octave>
</pitch>
<duration>1</duration>
<voice>5</voice>
<type>16th</type>
<stem>down</stem>
<staff>2</staff>
<beam number="1">continue</beam>
<beam number="2">continue</beam>
</note>
<note default-x="346.66" default-y="-115.00">
<pitch>
<step>F</step>
<alter>1</alter>
<octave>3</octave>
</pitch>
<duration>1</duration>
<voice>5</voice>
<type>16th</type>
<stem>down</stem>
<staff>2</staff>
<beam number="1">end</beam>
<beam number="2">end</beam>
</note>
<note default-x="432.76" default-y="-110.00">
<pitch>
<step>G</step>
<octave>3</octave>
</pitch>
<duration>4</duration>
<voice>5</voice>
<type>quarter</type>
<stem>down</stem>
<staff>2</staff>
</note>
<direction placement="below">
<direction-type>
<pedal type="stop" line="yes"/>
</direction-type>
<staff>2</staff>
</direction>
</measure>
<measure number="2" width="448.31">
<barline location="left">
<bar-style>heavy-light</bar-style>
<repeat direction="forward"/>
</barline>
<attributes>
<time>
<beats>3</beats>
<beat-type>8</beat-type>
</time>
</attributes>
<direction placement="above">
<direction-type>
<metronome parentheses="no">
<beat-unit>quarter</beat-unit>
<per-minute>80</per-minute>
</metronome>
</direction-type>
<staff>1</staff>
<sound tempo="79.9998"/>
</direction>
<note default-x="37.50" default-y="-25.00">
<pitch>
<step>A</step>
<octave>4</octave>
</pitch>
<duration>2</duration>
<tie type="start"/>
<voice>1</voice>
<type>eighth</type>
<stem>down</stem>
<staff>1</staff>
<beam number="1">begin</beam>
<notations>
<tied type="start"/>
</notations>
</note>
<note default-x="37.50" default-y="-5.00">
<chord/>
<pitch>
<step>E</step>
<octave>5</octave>
</pitch>
<duration>2</duration>
<voice>1</voice>
<type>eighth</type>
<stem>down</stem>
<staff>1</staff>
</note>
<note default-x="168.06" default-y="-5.00">
<pitch>
<step>E</step>
<octave>5</octave>
</pitch>
<duration>2</duration>
<voice>1</voice>
<type>eighth</type>
<stem>down</stem>
<staff>1</staff>
<beam number="1">end</beam>
</note>
<note default-x="298.62" default-y="-25.00">
<pitch>
<step>A</step>
<octave>4</octave>
</pitch>
<duration>2</duration>
<tie type="stop"/>
<voice>1</voice>
<type>eighth</type>
<stem>down</stem>
<staff>1</staff>
<notations>
<tied type="stop"/>
</notations>
</note>
<note default-x="298.62" default-y="-10.00">
<chord/>
<pitch>
<step>D</step>
<octave>5</octave>
</pitch>
<duration>2</duration>
<voice>1</voice>
<type>eighth</type>
<stem>down</stem>
<staff>1</staff>
</note>
<backup>
<duration>6</duration>
</backup>
<direction placement="below">
<direction-type>
<pedal type="start" line="yes"/>
</direction-type>
<staff>2</staff>
</direction>
<note default-x="37.50" default-y="-110.00">
<pitch>
<step>G</step>
<octave>3</octave>
</pitch>
<duration>6</duration>
<voice>5</voice>
<type>quarter</type>
<dot/>
<stem>down</stem>
<staff>2</staff>
</note>
<direction placement="below">
<direction-type>
<pedal type="stop" line="yes"/>
</direction-type>
<staff>2</staff>
</direction>
<barline location="right">
<bar-style>light-heavy</bar-style>
<repeat direction="backward"/>
</barline>
</measure>
</part>
</score-partwise>
答案 0 :(得分：1)
我的解决方案是迭代所有音符并获得音乐属性：
import music21 as m
song = m.converter.parse('test.xml')
# process the ties
song = song.stripTies()
# unfold repetitions
i = 0;
for a in song:
if a.isStream:
e = m.repeat.Expander(a)
s2 = e.process()
timing = s2.secondsMap
song[i] = s2
i += 1;
# todo: add note onsets
def getMusicProperties(x):
s = '';
t='';
s = str(x.pitch) + ", " + str(x.duration.type) + ", " + str(x.duration.quarterLength);
s += ", "
if x.tie != None:
t = x.tie.type;
s += t + ", " + str(x.pitch.ps) + ", " + str(x.octave); # + str(x.seconds) # x.seconds not always there
return s
print('pitch, duration_string, duration, tie, midi pitch, octave')
for a in song.recurse().notes:
if (a.isNote):
x = a;
s = getMusicProperties(x);
print(s);
if (a.isChord):
for x in a._notes:
s = getMusicProperties(x);
print(s);
print("Done.")
要获得绝对音符开头，我们可以使用：
for el in song.recurse():
totalOffset = el.getOffsetInHierarchy(song)
答案 1 :(得分：0)
您可以通过执行findall('.//note')迭代所有笔记，然后遍历子项以获取每个标记和文本，或者您需要的任何其他内容。
>>> import xml.etree.ElementTree as ET
>>> root = ET.parse('music.xml').getroot()
>>> for note in root.findall(".//note"):
... for elem in note:
... print elem.tag, elem.text
... print
...
rest None
duration 8
voice 1
staff 1
pitch
duration 1
voice 5
type 16th
stem down
staff 2
beam begin
beam begin