""" RealMedia (.rm) parser Author: Mike Melanson Creation date: 15 december 2006 References: - http://wiki.multimedia.cx/index.php?title=RealMedia - Appendix E: RealMedia File Format (RMFF) Reference https://common.helixcommunity.org/nonav/2003/HCS_SDK_r5/htmfiles/rmff.htm Samples: - http://samples.mplayerhq.hu/real/ """ from hachoir.parser import Parser from hachoir.field import (FieldSet, UInt16, UInt32, Bit, RawBits, RawBytes, String, PascalString8, PascalString16) from hachoir.core.text_handler import textHandler, hexadecimal from hachoir.core.endian import BIG_ENDIAN def parseHeader(self): yield UInt32(self, "filever", "File version") yield UInt32(self, "numheaders", "number of headers") def parseFileProperties(self): yield UInt32(self, "max_bit_rate", "Maximum bit rate") yield UInt32(self, "avg_bit_rate", "Average bit rate") yield UInt32(self, "max_pkt_size", "Size of largest data packet") yield UInt32(self, "avg_pkt_size", "Size of average data packet") yield UInt32(self, "num_pkts", "Number of data packets") yield UInt32(self, "duration", "File duration in milliseconds") yield UInt32(self, "preroll", "Suggested preroll in milliseconds") yield textHandler(UInt32(self, "index_offset", "Absolute offset of first index chunk"), hexadecimal) yield textHandler(UInt32(self, "data_offset", "Absolute offset of first data chunk"), hexadecimal) yield UInt16(self, "stream_count", "Number of streams in the file") yield RawBits(self, "reserved", 13) yield Bit(self, "is_live", "Whether file is a live broadcast") yield Bit(self, "is_perfect_play", "Whether PerfectPlay can be used") yield Bit(self, "is_saveable", "Whether file can be saved") def parseContentDescription(self): yield PascalString16(self, "title", charset="ISO-8859-1", strip=" \0") yield PascalString16(self, "author", charset="ISO-8859-1", strip=" \0") yield PascalString16(self, "copyright", charset="ISO-8859-1", strip=" \0") yield PascalString16(self, "comment", charset="ISO-8859-1", strip=" \0") class NameValueProperty(FieldSet): def __init__(self, *args): FieldSet.__init__(self, *args) self._size = self["size"].value * 8 def createFields(self): yield UInt32(self, "size") yield UInt16(self, "obj_version") yield PascalString8(self, "name", charset="ASCII") yield UInt32(self, "type") yield PascalString16(self, "value", charset="ISO-8859-1", strip=" \0") class LogicalFileInfo(FieldSet): def createFields(self): yield UInt32(self, "size") yield UInt16(self, "obj_version") yield UInt16(self, "nb_physical_stream") for index in range(self["nb_physical_stream"].value): yield UInt16(self, "physical_stream[]") for index in range(self["nb_physical_stream"].value): yield UInt16(self, "data_offset[]") yield UInt16(self, "nb_rule") for index in range(self["nb_rule"].value): yield UInt16(self, "rule[]") yield UInt16(self, "nb_prop") for index in range(self["nb_prop"].value): yield NameValueProperty(self, "prop[]") def parseMediaPropertiesHeader(self): yield UInt16(self, "stream_number", "Stream number") yield UInt32(self, "max_bit_rate", "Maximum bit rate") yield UInt32(self, "avg_bit_rate", "Average bit rate") yield UInt32(self, "max_pkt_size", "Size of largest data packet") yield UInt32(self, "avg_pkt_size", "Size of average data packet") yield UInt32(self, "stream_start", "Stream start offset in milliseconds") yield UInt32(self, "preroll", "Preroll in milliseconds") yield UInt32(self, "duration", "Stream duration in milliseconds") yield PascalString8(self, "desc", "Stream description", charset="ISO-8859-1") yield PascalString8(self, "mime_type", "MIME type string", charset="ASCII") yield UInt32(self, "specific_size", "Size of type-specific data") size = self['specific_size'].value if size: if self["mime_type"].value == "logical-fileinfo": yield LogicalFileInfo(self, "file_info", size=size * 8) else: yield RawBytes(self, "specific", size, "Type-specific data") class Chunk(FieldSet): tag_info = { ".RMF": ("header", parseHeader), "PROP": ("file_prop", parseFileProperties), "CONT": ("content_desc", parseContentDescription), "MDPR": ("stream_prop[]", parseMediaPropertiesHeader), "DATA": ("data[]", None), "INDX": ("file_index[]", None) } def createValueFunc(self): return self.value_func(self) def __init__(self, parent, name, description=None): FieldSet.__init__(self, parent, name, description) self._size = (self["size"].value) * 8 tag = self["tag"].value if tag in self.tag_info: self._name, self.parse_func = self.tag_info[tag] else: self._description = "" self.parse_func = None def createFields(self): yield String(self, "tag", 4, "Chunk FourCC", charset="ASCII") yield UInt32(self, "size", "Chunk Size") yield UInt16(self, "version", "Chunk Version") if self.parse_func: yield from self.parse_func(self) else: size = (self.size - self.current_size) // 8 if size: yield RawBytes(self, "raw", size) def createDescription(self): return "Chunk: %s" % self["tag"].display class RealMediaFile(Parser): MAGIC = b'.RMF\0\0\0\x12\0\1' # (magic, size=18, version=1) PARSER_TAGS = { "id": "real_media", "category": "container", "file_ext": ("rm",), "mime": ( "video/x-pn-realvideo", "audio/x-pn-realaudio", "audio/x-pn-realaudio-plugin", "audio/x-real-audio", "application/vnd.rn-realmedia"), "min_size": len(MAGIC) * 8, # just the identifier "magic": ((MAGIC, 0),), "description": "RealMedia (rm) Container File", } endian = BIG_ENDIAN def validate(self): if self.stream.readBytes(0, 4) != b'.RMF': return "Invalid magic" if self["header/size"].value != 18: return "Invalid header size" if self["header/version"].value not in (0, 1): return "Unknown file format version (%s)" % self["header/version"].value return True def createFields(self): while not self.eof: yield Chunk(self, "chunk") def createMimeType(self): for prop in self.array("stream_prop"): if prop["mime_type"].value == "video/x-pn-realvideo": return "video/x-pn-realvideo" return "audio/x-pn-realaudio"