Rtpdump (rtptools): Python parsing library

rtpdump is a format used by rtptools to record and replay rtp data from network capture.

File extension

["rtp", "rtpdump"]

KS implementation details

License: Unlicense

This page hosts a formal specification of Rtpdump (rtptools) using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.

The Python runtime library can be installed from PyPI:

python3 -m pip install kaitaistruct

Code

Parse a local file and get structure in memory:

data = Rtpdump.from_file("path/to/local/file.rtp")

Or parse structure from a bytes:

from kaitaistruct import KaitaiStream, BytesIO

raw = b"\x00\x01\x02..."
data = Rtpdump(KaitaiStream(BytesIO(raw)))

After that, one can get various attributes from the structure by invoking getter methods like:

data.file_header # => get file header

Python source code to parse Rtpdump (rtptools)

rtpdump.py

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO


if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
    raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))

import rtp_packet
class Rtpdump(KaitaiStruct):
    """rtpdump is a format used by rtptools to record and replay
    rtp data from network capture.
    
    .. seealso::
       Source - https://chromium.googlesource.com/external/webrtc/stable/talk/+/master/media/base/rtpdump.h
    """
    def __init__(self, _io, _parent=None, _root=None):
        self._io = _io
        self._parent = _parent
        self._root = _root if _root else self
        self._read()

    def _read(self):
        self.file_header = Rtpdump.HeaderT(self._io, self, self._root)
        self.packets = []
        i = 0
        while not self._io.is_eof():
            self.packets.append(Rtpdump.PacketT(self._io, self, self._root))
            i += 1


    class HeaderT(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            self._io = _io
            self._parent = _parent
            self._root = _root if _root else self
            self._read()

        def _read(self):
            self.shebang = self._io.read_bytes(12)
            if not self.shebang == b"\x23\x21\x72\x74\x70\x70\x6C\x61\x79\x31\x2E\x30":
                raise kaitaistruct.ValidationNotEqualError(b"\x23\x21\x72\x74\x70\x70\x6C\x61\x79\x31\x2E\x30", self.shebang, self._io, u"/types/header_t/seq/0")
            self.space = self._io.read_bytes(1)
            if not self.space == b"\x20":
                raise kaitaistruct.ValidationNotEqualError(b"\x20", self.space, self._io, u"/types/header_t/seq/1")
            self.ip = (self._io.read_bytes_term(47, False, True, True)).decode(u"ascii")
            self.port = (self._io.read_bytes_term(10, False, True, True)).decode(u"ascii")
            self.start_sec = self._io.read_u4be()
            self.start_usec = self._io.read_u4be()
            self.ip2 = self._io.read_u4be()
            self.port2 = self._io.read_u2be()
            self.padding = self._io.read_u2be()


    class PacketT(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            self._io = _io
            self._parent = _parent
            self._root = _root if _root else self
            self._read()

        def _read(self):
            self.length = self._io.read_u2be()
            self.len_body = self._io.read_u2be()
            self.packet_usec = self._io.read_u4be()
            self._raw_body = self._io.read_bytes(self.len_body)
            _io__raw_body = KaitaiStream(BytesIO(self._raw_body))
            self.body = rtp_packet.RtpPacket(_io__raw_body)