1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
# Copyright 2024 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# -----------------------------------------------------------------------------
# Imports
# -----------------------------------------------------------------------------
from __future__ import annotations
import struct
# -----------------------------------------------------------------------------
class MediaPacket:
@staticmethod
def from_bytes(data: bytes) -> MediaPacket:
version = (data[0] >> 6) & 0x03
padding = (data[0] >> 5) & 0x01
extension = (data[0] >> 4) & 0x01
csrc_count = data[0] & 0x0F
marker = (data[1] >> 7) & 0x01
payload_type = data[1] & 0x7F
sequence_number = struct.unpack_from('>H', data, 2)[0]
timestamp = struct.unpack_from('>I', data, 4)[0]
ssrc = struct.unpack_from('>I', data, 8)[0]
csrc_list = [
struct.unpack_from('>I', data, 12 + i)[0] for i in range(csrc_count)
]
payload = data[12 + csrc_count * 4 :]
return MediaPacket(
version,
padding,
extension,
marker,
sequence_number,
timestamp,
ssrc,
csrc_list,
payload_type,
payload,
)
def __init__(
self,
version: int,
padding: int,
extension: int,
marker: int,
sequence_number: int,
timestamp: int,
ssrc: int,
csrc_list: list[int],
payload_type: int,
payload: bytes,
) -> None:
self.version = version
self.padding = padding
self.extension = extension
self.marker = marker
self.sequence_number = sequence_number & 0xFFFF
self.timestamp = timestamp & 0xFFFFFFFF
self.timestamp_seconds = 0.0
self.ssrc = ssrc
self.csrc_list = csrc_list
self.payload_type = payload_type
self.payload = payload
def __bytes__(self) -> bytes:
header = bytes(
[
self.version << 6
| self.padding << 5
| self.extension << 4
| len(self.csrc_list),
self.marker << 7 | self.payload_type,
]
) + struct.pack(
'>HII',
self.sequence_number,
self.timestamp,
self.ssrc,
)
for csrc in self.csrc_list:
header += struct.pack('>I', csrc)
return header + self.payload
def __str__(self) -> str:
return (
f'RTP(v={self.version},'
f'p={self.padding},'
f'x={self.extension},'
f'm={self.marker},'
f'pt={self.payload_type},'
f'sn={self.sequence_number},'
f'ts={self.timestamp},'
f'ssrc={self.ssrc},'
f'csrcs={self.csrc_list},'
f'payload_size={len(self.payload)})'
)
|
