SickGear/lib/hachoir_parser/audio/real_audio.py
2015-08-20 16:48:28 +01:00

90 lines
3.7 KiB
Python

"""
RealAudio (.ra) parser
Author: Mike Melanson
References:
http://wiki.multimedia.cx/index.php?title=RealMedia
Samples:
http://samples.mplayerhq.hu/real/RA/
"""
from hachoir_parser import Parser
from hachoir_core.field import (FieldSet,
UInt8, UInt16, UInt32,
Bytes, RawBytes, String,
PascalString8)
from hachoir_core.tools import humanFrequency
from hachoir_core.text_handler import displayHandler
from hachoir_core.endian import BIG_ENDIAN
class Metadata(FieldSet):
def createFields(self):
yield PascalString8(self, "title", charset="ISO-8859-1")
yield PascalString8(self, "author", charset="ISO-8859-1")
yield PascalString8(self, "copyright", charset="ISO-8859-1")
yield PascalString8(self, "comment", charset="ISO-8859-1")
class RealAudioFile(Parser):
MAGIC = ".ra\xFD"
PARSER_TAGS = {
"id": "real_audio",
"category": "audio",
"file_ext": ["ra"],
"mime": (u"audio/x-realaudio", u"audio/x-pn-realaudio"),
"min_size": 6*8,
"magic": ((MAGIC, 0),),
"description": u"Real audio (.ra)",
}
endian = BIG_ENDIAN
def validate(self):
if self["signature"].value != self.MAGIC:
return "Invalid signature"
if self["version"].value not in (3, 4):
return "Unknown version"
return True
def createFields(self):
yield Bytes(self, "signature", 4, r"RealAudio identifier ('.ra\xFD')")
yield UInt16(self, "version", "Version")
if self["version"].value == 3:
yield UInt16(self, "header_size", "Header size")
yield RawBytes(self, "Unknown1", 10)
yield UInt32(self, "data_size", "Data size")
yield Metadata(self, "metadata")
yield UInt8(self, "Unknown2")
yield PascalString8(self, "FourCC")
audio_size = self["data_size"].value
else: # version = 4
yield UInt16(self, "reserved1", "Reserved, should be 0")
yield String(self, "ra4sig", 4, "'.ra4' signature")
yield UInt32(self, "filesize", "File size (minus 40 bytes)")
yield UInt16(self, "version2", "Version 2 (always equal to version)")
yield UInt32(self, "headersize", "Header size (minus 16)")
yield UInt16(self, "codec_flavor", "Codec flavor")
yield UInt32(self, "coded_frame_size", "Coded frame size")
yield RawBytes(self, "unknown1", 12)
yield UInt16(self, "subpacketh", "Subpacket h (?)")
yield UInt16(self, "frame_size", "Frame size")
yield UInt16(self, "sub_packet_size", "Subpacket size")
yield UInt16(self, "unknown2", "Unknown")
yield displayHandler(UInt16(self, "sample_rate", "Sample rate"), humanFrequency)
yield UInt16(self, "unknown3", "Unknown")
yield UInt16(self, "sample_size", "Sample size")
yield UInt16(self, "channels", "Channels")
yield PascalString8(self, "Interleaving ID String")
yield PascalString8(self, "FourCC")
yield RawBytes(self, "unknown4", 3)
yield Metadata(self, "metadata")
audio_size = (self["filesize"].value + 40) - (self["headersize"].value + 16)
if 0 < audio_size:
yield RawBytes(self, "audio_data", audio_size)
def createDescription(self):
if (self["version"].value == 3):
return "RealAudio v3 file, '%s' codec" % self["FourCC"].value
elif (self["version"].value == 4):
return "RealAudio v4 file, '%s' codec, %s, %u channels" % (
self["FourCC"].value, self["sample_rate"].display, self["channels"].value)
else:
return "Real audio"