mutagen/id3.py
def update_to_v24(self):
        """Convert older tags into an ID3v2.4 tag.

        This updates old ID3v2 frames to ID3v2.4 ones (e.g. TYER to
        TDRC). If you intend to save tags, you must call this function
        at some point; it is called by default when loading the tag.
        """

        self.__update_common()

        if self.__unknown_version == self._V23:
            # convert unknown 2.3 frames (flags/size) to 2.4
            converted = []
            for frame in self.unknown_frames:
                try:
                    name, size, flags = unpack('>4sLH', frame[:10])
                    frame = BinaryFrame.fromData(self, flags, frame[10:])
                except (struct.error, error):
                    continue
                name = name.decode('ascii')
                converted.append(self.__save_frame(frame, name=name))
            self.unknown_frames[:] = converted
            self.__unknown_version = self._V24

        # TDAT, TYER, and TIME have been turned into TDRC.
        try:
            date = text_type(self.get("TYER", ""))
            if date.strip(u"\x00"):
                self.pop("TYER")
                dat = text_type(self.get("TDAT", ""))
                if dat.strip("\x00"):
                    self.pop("TDAT")
                    date = "%s-%s-%s" % (date, dat[2:], dat[:2])
                    time = text_type(self.get("TIME", ""))
                    if time.strip("\x00"):
                        self.pop("TIME")
                        date += "T%s:%s:00" % (time[:2], time[2:])
                if "TDRC" not in self:
                    self.add(TDRC(encoding=0, text=date))
        except UnicodeDecodeError:
            # Old ID3 tags have *lots* of Unicode problems, so if TYER
            # is bad, just chuck the frames.
            pass

        # TORY can be the first part of a TDOR.
        if "TORY" in self:
            f = self.pop("TORY")
            if "TDOR" not in self:
                try:
                    self.add(TDOR(encoding=0, text=str(f)))
                except UnicodeDecodeError:
                    pass

        # IPLS is now TIPL.
        if "IPLS" in self:
            f = self.pop("IPLS")
            if "TIPL" not in self:
                self.add(TIPL(encoding=f.encoding, people=f.people))

        # These can't be trivially translated to any ID3v2.4 tags, or
        # should have been removed already.
        for key in ["RVAD", "EQUA", "TRDA", "TSIZ", "TDAT", "TIME", "CRM"]:
            if key in self:
                del(self[key])
def update_to_v24(self):
        """Convert older tags into an ID3v2.4 tag.

        This updates old ID3v2 frames to ID3v2.4 ones (e.g. TYER to
        TDRC). If you intend to save tags, you must call this function
        at some point; it is called by default when loading the tag.
        """

        self.__update_common()

        if self.__unknown_version == self._V23:
            # convert unknown 2.3 frames (flags/size) to 2.4
            converted = []
            for frame in self.unknown_frames:
                try:
                    name, size, flags = unpack('>4sLH', frame[:10])
                    frame = BinaryFrame.fromData(self, flags, frame[10:])
                except (struct.error, error):
                    continue
                name = name.decode('ascii')
                converted.append(self.__save_frame(frame, name=name))
            self.unknown_frames[:] = converted
            self.__unknown_version = self._V24

        # TDAT, TYER, and TIME have been turned into TDRC.
        try:
            date = text_type(self.get("TYER", ""))
            if date.strip(u"\x00"):
                self.pop("TYER")
                dat = text_type(self.get("TDAT", ""))
                if dat.strip("\x00"):
                    self.pop("TDAT")
                    date = "%s-%s-%s" % (date, dat[2:], dat[:2])
                    time = text_type(self.get("TIME", ""))
                    if time.strip("\x00"):
                        self.pop("TIME")
                        date += "T%s:%s:00" % (time[:2], time[2:])
                if "TDRC" not in self:
                    self.add(TDRC(encoding=0, text=date))
        except UnicodeDecodeError:
            # Old ID3 tags have *lots* of Unicode problems, so if TYER
            # is bad, just chuck the frames.
            pass

        # TORY can be the first part of a TDOR.
        if "TORY" in self:
            f = self.pop("TORY")
            if "TDOR" not in self:
                try:
                    self.add(TDOR(encoding=0, text=str(f)))
                except UnicodeDecodeError:
                    pass

        # IPLS is now TIPL.
        if "IPLS" in self:
            f = self.pop("IPLS")
            if "TIPL" not in self:
                self.add(TIPL(encoding=f.encoding, people=f.people))

        # These can't be trivially translated to any ID3v2.4 tags, or
        # should have been removed already.
        for key in ["RVAD", "EQUA", "TRDA", "TSIZ", "TDAT", "TIME", "CRM"]:
            if key in self:
                del(self[key])
Convert older tags into an ID3v2.4 tag.

        This updates old ID3v2 frames to ID3v2.4 ones (e.g. TYER to
        TDRC). If you intend to save tags, you must call this function
        at some point; it is called by default when loading the tag.