def __init__(self, header_data, xheader_data):
"""Interprets byte data as a tag header to build object
Args:
header_data: character array of bytes representing the tag header.
Must contain an ID3v1 tag
xheader_data: character array of bytes representing the extended tag
header. This does not have to contain an extended header (in
which case it will be ignored).
"""
# Check we're actually looking at an ID3v1 tag
if header_data[:3] != "TAG":
raise Exception("Given data does not contain an ID3v1 tag header")
# Extract data
self.data = TrackData.TrackData()
self.data.title = _strip_null_bytes(header_data[3:33])
self.data.artist = _strip_null_bytes(header_data[33:63])
self.data.album = _strip_null_bytes(header_data[63:93])
self.data.year = TrackData.mint(_strip_null_bytes(header_data[93:97]))
if ord(header_data[125]) == 0 and ord(header_data[126]) != 0:
self.version = 1 # id3 v1.1
self.comment = _strip_null_bytes(header_data[97:125])
self.data.track = ord(header_data[126])
else:
self.version = 0 # id3 v1.0
self.comment = _strip_null_bytes(header_data[97:127])
self.data.track = None
self.genre = ord(header_data[127])
# Check if we have an extended tag and extract it
self.is_extended = xheader_data[:4] == "TAG+"
if self.is_extended:
self.data.title += _strip_null_bytes(xheader_data[4:64])
self.data.artist += _strip_null_bytes(xheader_data[64:124])
self.data.album += _strip_null_bytes(xheader_data[124:184])
def get_year(self, file_handle):
"""Retrieves the track year from this tag
Args:
file_handle: open file handle to read the frame body from
Returns:
int track year or None if this tag doesn't contain it
"""
version = self.header.version
if version == 2:
frame_id = "TYE"
elif version == 3 or version == 4:
frame_id = "TYER"
else:
return None
frame = self.__get_frame(frame_id)
if frame:
body_data = _read_frame_text(frame.read_body(file_handle))
return TrackData.mint(body_data[0:4])
return None
