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# mutagen aims to be an all purpose media tagging library
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# Copyright (C) 2005 Michael Urman
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of version 2 of the GNU General Public License as
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# published by the Free Software Foundation.
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# $Id: __init__.py 2971 2006-03-13 22:16:49Z piman $
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mutagen aims to be an all purpose tagging library.
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import mutagen.[format]
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metadata = mutagen.[format].Open(filename)
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metadata acts like a dictionary of tags in the file. Tags are generally a
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list of string-like values, but may have additional methods available
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depending on tag or format. They may also be entirely different objects
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for certain keys, again depending on format.
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"""Abstract dict-like object that each format inherits for managing
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def __init__(self, filename=None, fileobj=None):
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"""Initializes a tag structure. If fileobj is specified it is the
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source and must include a "read" method or an AttributeError will be
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raised. Otherwise if filename is specified it must exist and be
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readable or normal exceptions will be thrown. Finally for various kinds
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of bad data, a subclass of ValueError may be thrown."""
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raise NotImplementedError
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def save(self, filename=None):
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"""Save metadata to previously referenced or newly specified file"""
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raise NotImplementedError
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"""Remove tags from the open file"""
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raise NotImplementedError
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def _insert_space(fobj, size, offset):
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"""insert size bytes of empty space starting at offset. fobj must be
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an open file object, open rb+ or equivalent."""
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filesize = fobj.tell()
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movesize = filesize - offset
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fobj.write('\x00' * size)
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map = mmap(fobj.fileno(), filesize + size)
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map.move(offset+size, offset, movesize)
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except ValueError: # handle broken python on 64bit
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fobj.truncate(filesize)
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backbuf = fobj.read(size)
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if len(backbuf) < size:
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fobj.write('\x00' * (size - len(backbuf)))
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while len(backbuf) == size:
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frontbuf = fobj.read(size)
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fobj.seek(-len(frontbuf), 1)
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_insert_space = staticmethod(_insert_space)
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def _delete_bytes(fobj, size, offset):
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"""delete size bytes of data starting at offset. fobj must be
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an open file object, open rb+ or equivalent."""
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filesize = fobj.tell()
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movesize = filesize - offset - size
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map = mmap(fobj.fileno(), filesize)
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map.move(offset, offset+size, movesize)
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except ValueError: # handle broken python on 64bit
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fobj.seek(offset + size)
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fobj.seek(-len(buf) - size, 1)
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buf = fobj.read(size)
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fobj.truncate(filesize - size)
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_delete_bytes = staticmethod(_delete_bytes)
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class FileType(object):
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"""Abstract object that provides a specific type of file format.
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Any metadata tags are exposed as .tags (and looks basically like a dict),
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and the audio info is exposed as .info, which has at least a length
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def __getitem__(self, key):
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if self.tags is None: raise KeyError, key
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else: return self.tags[key]
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def __setitem__(self, key, value):
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if self.tags is None: self.add_tags()
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self.tags[key] = value
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def __delitem__(self, key):
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if self.tags is None: raise KeyError, key
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else: del(self.tags[key])
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if self.tags is None: return []
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else: return self.tags.keys()
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if self.tags is None: return []
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else: return self.tags.values()
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if self.tags is None: return []
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else: return self.tags.items()
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"""Remove tags from a file."""
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if self.tags is not None: self.tags.delete()
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def save(self, filename=None, **kwargs):
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if filename is None: filename = self.filename
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if self.tags is not None:
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self.tags.save(filename, **kwargs)
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else: raise ValueError("no tags in file")
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mutagen/__init__.py
