我想自动压缩我的电影。所以我在python中编写了一个mediainfo包装器类来生成一个xml输出，然后我用一个音频和字幕轨道列表解析为movieinfo类。
__author__ = 'dominik'
class Error(Exception):
""" Error class
"""
class ValidationError(Error):
""" Invalid or missing xml items
"""
class MovieInfo(object):
""" Description of movie file
"""
def __init__(self, media_info):
self._video_track = None
self._audio_tracks = []
self._subtitle_tracks = []
self.valid_movie = True
for track in media_info.tracks:
if track.track_type == "Audio":
self._audio_tracks.append(AudioTrack(track))
elif track.track_type == "Text":
self._subtitle_tracks.append(SubtitleTrack(track))
elif track.track_type == "Video":
self._video_track = VideoTrack(track)
@property
def audio_tracks(self):
if not hasattr(self, "_audio_tracks"):
self._audio_tracks = []
if len(self._audio_tracks) != 0:
return self._audio_tracks
@property
def subtitle_tracks(self):
if not hasattr(self, "_subtitle_tracks"):
self._subtitle_tracks = []
if len(self._subtitle_tracks) != 0:
return self._subtitle_tracks
class Track(object):
""" Abstract track class for audio and subtitle tracks
"""
__KNOWN_LANGUAGE_CODES = {"en": "ENG", "de": "DE"}
def __init__(self, track, valid_codecs):
self._valid = True
track_id = int(track.id)
codec_id = self._determine_codec(track.codec_id, valid_codecs)
language = self._determine_language(track.language)
self._id = track_id
self._codec_id = codec_id
self._language = language
def _determine_codec(self, track_codec, types):
result = types.get(track_codec, None)
if result is None:
self._valid = False
return result
def _determine_language(self, track_language, types=__KNOWN_LANGUAGE_CODES):
result = types.get(track_language, None)
if result is None:
self._valid = False
return result
class AudioTrack(Track):
""" Audio track class
"""
__KNOWN_AUDIO_CODECS = {"A_DTS": "DTS", "A_AC3": "AC3"}
def __init__(self, track):
self._type = 1
Track.__init__(self, track, self.__KNOWN_AUDIO_CODECS)
class SubtitleTrack(Track):
""" Subtitle track class
"""
__KNOWN_SUBTITLE_CODECS = {"S_VOBSUB": "VOBSUB"}
def __init__(self, track):
self._type = 2
if track.forced == "Yes":
self._forced = True
else:
self._forced = False
Track.__init__(self, track, self.__KNOWN_SUBTITLE_CODECS)
class VideoTrack(object):
""" Video track class (only one video track in movie info!)
"""
def __init__(self, track):
self._type = 0
self._framerate = float(track.frame_rate)
self._width = track.width
self._height = track.height
这是mediainfo类（它是pymediainfo类）：
from subprocess import Popen
import os
from tempfile import mkstemp
from bs4 import BeautifulSoup, NavigableString
from setuptools.compat import unicode
class Track(object):
""" Hold the track information
"""
def __getattr__(self, item):
try:
return object.__getattribute__(self, item)
except:
pass
return None
def __init__(self, xml_track):
self.xml_track = xml_track
self.track_type = xml_track.attrs["type"]
for child in self.xml_track.children:
if not isinstance(child, NavigableString):
node_name = child.name.lower().strip()
node_value = unicode(child.string)
node_other_name = "other_%s" % node_name
if getattr(self, node_name) is None:
setattr(self, node_name, node_value)
else:
if getattr(self, node_other_name) is None:
setattr(self, node_other_name, [node_value, ])
else:
getattr(self, node_other_name).append(node_value)
for key in [c for c in self.__dict__.keys() if c.startswith("other_")]:
try:
primary = key.replace("other_", "")
setattr(self, primary, int(getattr(self, primary)))
except:
for value in getattr(self, key):
try:
actual = getattr(self, primary)
setattr(self, primary, int(value))
getattr(self, key).append(actual)
break
except:
pass
def __repr__(self):
return("<Track id='{0}', type='{1}'>".format(self.id, self.track_type))
def to_data(self):
data = {}
for k, v in self.__dict__.items():
if k != 'xml_track':
data[k] = v
return data
class Mediainfo(object):
""" MediaInfo wrapper
"""
def __init__(self, xml):
self.xml_dom = xml
if isinstance(xml, str):
self.xml_dom = BeautifulSoup(xml, "xml")
def _populate_tracks(self):
if self.xml_dom is None:
return
for xml_track in self.xml_dom.Mediainfo.File.find_all("track"):
self._tracks.append(Track(xml_track))
@property
def tracks(self):
if not hasattr(self, "_tracks"):
self._tracks = []
if len(self._tracks) == 0:
self._populate_tracks()
return self._tracks
@staticmethod
def parse(filename):
filehandler_out, filename_out = mkstemp(".xml", "mediainfo-")
filehandler_err, filename_err = mkstemp(".error", "mediainfo-")
filepointer_out = os.fdopen(filehandler_out, "r+b")
filepointer_err = os.fdopen(filehandler_err, "r+b")
mediainfo_command = ["mediainfo", "-f", "--Output=XML", filename]
p = Popen(mediainfo_command, stdout=filepointer_out, stderr=filepointer_err)
p.wait()
filepointer_out.seek(0)
xml_dom = BeautifulSoup(filepointer_out.read(), "xml")
filepointer_out.close()
filepointer_err.close()
print(xml_dom)
return Mediainfo(xml_dom)
def to_data(self):
data = {'tracks': []}
for track in self.tracks:
data['tracks'].append(track.to_data())
return data
这个类给了我xml中的每个轨道，然后我解析了movieinfo中的相关信息。
好的，我现在有一个录音带列表，例如3个用德语和DTS跟踪一个，一个用德语和AC3跟踪，一个用英语和AC3跟踪。现在我想以“1,2,3”的格式从轨道中获取ID，以便将其提供给手刹cli。
我的问题是曲目的顺序。如果存在德国DTS音轨，则该音轨应该是第一音轨，第二音轨也应该是第一音轨，但是压缩到aac，第三音轨应该是AAC中的一首英语音轨。如果只有德国AC3音轨，那么第一首音轨应该是这首音轨但是压缩到AAC，第二首音轨应该是AAC和AAC。 我不确切知道如何实现这一点，你能帮助我吗？我是python的新手，来自C，C ++和C＃。在C＃中，使用lambda非常容易。
答案 0 :(得分：0)
假设您知道要定义一个比较器，给定两个项可以定义哪个比Python更大，那么Python函数以及C或C ++。
从这里开始 - 1. https://wiki.python.org/moin/HowTo/Sorting/