本文整理汇总了Python中EventDispatcher.EventDispatcher.header方法的典型用法代码示例。如果您正苦于以下问题：Python EventDispatcher.header方法的具体用法？Python EventDispatcher.header怎么用？Python EventDispatcher.header使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类EventDispatcher.EventDispatcher的用法示例。
在下文中一共展示了EventDispatcher.header方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: __init__
# 需要导入模块: from EventDispatcher import EventDispatcher [as 别名]
# 或者: from EventDispatcher.EventDispatcher import header [as 别名]
class MidiFileParser:
"""
The MidiFileParser is the lowest level parser that see the data as
midi data. It generates events that gets triggered on the outstream.
"""
def __init__(self, raw_in, outstream):
"""
raw_data is the raw content of a midi file as a string.
"""
# internal values, don't mess with 'em directly
self.raw_in = raw_in
self.dispatch = EventDispatcher(outstream)
# Used to keep track of stuff
self._running_status = None
def parseMThdChunk(self):
"Parses the header chunk"
raw_in = self.raw_in
header_chunk_type = raw_in.nextSlice(4)
header_chunk_zise = raw_in.readBew(4)
# check if it is a proper midi file
if header_chunk_type != 'MThd':
raise TypeError, "It is not a valid midi file!"
# Header values are at fixed locations, so no reason to be clever
self.format = raw_in.readBew(2)
self.nTracks = raw_in.readBew(2)
self.division = raw_in.readBew(2)
# Theoretically a header larger than 6 bytes can exist
# but no one has seen one in the wild
# But correctly ignore unknown data if it is though
if header_chunk_zise > 6:
raw_in.moveCursor(header_chunk_zise-6)
# call the header event handler on the stream
self.dispatch.header(self.format, self.nTracks, self.division)
def parseMTrkChunk(self):
"Parses a track chunk. This is the most important part of the parser."
# set time to 0 at start of a track
self.dispatch.reset_time()
dispatch = self.dispatch
raw_in = self.raw_in
# Trigger event at the start of a track
dispatch.start_of_track(self._current_track)
# position cursor after track header
raw_in.moveCursor(4)
# unsigned long is 4 bytes
tracklength = raw_in.readBew(4)
track_endposition = raw_in.getCursor() + tracklength # absolute position!
while raw_in.getCursor() < track_endposition:
# find relative time of the event
time = raw_in.readVarLen()
dispatch.update_time(time)
# be aware of running status!!!!
peak_ahead = raw_in.readBew(move_cursor=0)
if (peak_ahead & 0x80):
# the status byte has the high bit set, so it
# was not running data but proper status byte
status = self._running_status = raw_in.readBew()
else:
# use that darn running status
status = self._running_status
# could it be illegal data ?? Do we need to test for that?
# I need more example midi files to be shure.
# Also, while I am almost certain that no realtime
# messages will pop up in a midi file, I might need to
# change my mind later.
# we need to look at nibbles here
hi_nible, lo_nible = status & 0xF0, status & 0x0F
# match up with events
# Is it a meta_event ??
#.........这里部分代码省略.........