forked from epiclabs-io/hls-analyzer
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ts_segment.py
177 lines (126 loc) · 5.77 KB
/
ts_segment.py
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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
# coding: utf-8
# Copyright 2014 jeoliva author. All rights reserved.
# Use of this source code is governed by a MIT License
# license that can be found in the LICENSE file.
from array import array
from bitreader import BitReader
from parsers.pesreader import PESReader
class TSSegmentParser(object):
MPEGTS_SYNC = 0x47
MPEGTS_PACKET_SIZE = 187
CONTAINER_UNKNOWN = 1
CONTAINER_MPEG_TS = 2
CONTAINER_RAW_AAC = 3
def __init__(self, data ):
self.data = data
self.dataOffset = 0
self.lastPts = 0
self.containerType = self.CONTAINER_UNKNOWN
self.pmtParsed = False
self.packetsCount = 0
self.pmtId = -1
self.tracks = dict()
def prepare(self):
self._findContainerType()
if(self.containerType == self.CONTAINER_MPEG_TS):
self._readHeader()
self.readSamples()
else:
dataParser = BitReader(self.data)
self.tracks[0] = PESReader(0, PESReader.TS_STREAM_TYPE_AAC)
self.tracks[0].appendData(0, dataParser)
self.tracks[0].payloadReader.consumeData(self.lastPts)
#print "\tPackets count: {}".format(self.packetsCount)
def getNumTracks(self):
return len(self.tracks)
def getTrack(self, index):
i = 0
for key, value in self.tracks.iteritems():
if(i == index):
return value
i = i + 1
def readSamples(self):
while (self.dataOffset < len(self.data) - 1):
byteRead = self.data[self.dataOffset]
self.dataOffset = self.dataOffset + 1
if(byteRead == self.MPEGTS_SYNC
and (len(self.data) - self.dataOffset) >= self.MPEGTS_PACKET_SIZE):
packet = self.data[self.dataOffset:self.dataOffset
+ self.MPEGTS_PACKET_SIZE]
self.dataOffset = self.dataOffset + self.MPEGTS_PACKET_SIZE
self._processTSPacket(packet)
def _findContainerType(self):
while (self.dataOffset < len(self.data)):
if (self.data[self.dataOffset] == self.MPEGTS_SYNC):
self.containerType = self.CONTAINER_MPEG_TS
break
elif((len(self.data) - self.dataOffset) >= 4):
dataRead = (self.data[self.dataOffset] << 8) | (self.data[self.dataOffset + 1])
if (dataRead == 0x4944 or (dataRead & 0xfff6) == 0xfff0):
self.containerType = self.CONTAINER_RAW_AAC
self.payloadStartIndex = 0
break
self.dataOffset = self.dataOffset + 1
if(self.containerType == self.CONTAINER_UNKNOWN):
raise Exception('Format not supported')
def _readHeader(self):
while (self.dataOffset < len(self.data) - 1):
byteRead = self.data[self.dataOffset]
self.dataOffset = self.dataOffset + 1
if(byteRead == self.MPEGTS_SYNC
and (len(self.data) - self.dataOffset) >= self.MPEGTS_PACKET_SIZE):
packet = self.data[self.dataOffset:self.dataOffset
+ self.MPEGTS_PACKET_SIZE]
self.dataOffset = self.dataOffset + self.MPEGTS_PACKET_SIZE
self._processTSPacket(packet)
if(self.pmtParsed):
break
def _processTSPacket(self, packet):
self.packetsCount = self.packetsCount + 1
packetParser = BitReader(packet)
packetParser.skipBits(1)
payload_unit_start_indicator = (packetParser.readBits(1) != 0)
packetParser.skipBits(1)
pid = packetParser.readBits(13)
adaptation_field = (packetParser.readUnsignedByte() & 0x30) >> 4
if (adaptation_field > 1):
length = packetParser.readUnsignedByte();
if (length > 0):
packetParser.skipBytes(length)
if (adaptation_field == 1 or adaptation_field == 3):
if (pid == 0):
self._parseProgramId(payload_unit_start_indicator, packetParser)
elif (pid == self.pmtId):
self._parseProgramTable(payload_unit_start_indicator, packetParser)
else:
track = self.tracks.get(pid, None)
if(track is not None):
track.appendData(payload_unit_start_indicator, packetParser)
def _parseProgramId(self, payload_unit_start_indicator, packetParser):
if (payload_unit_start_indicator):
packetParser.skipBytes( packetParser.readUnsignedByte() )
packetParser.skipBits(12)
sectionLength = packetParser.readBits(12)
packetParser.skipBits(3 + 7 * 8)
self.pmtId = packetParser.readBits(13)
#print "PMT Id: {}".format(self.pmtId)
def _parseProgramTable(self, payload_unit_start_indicator, packetParser):
if (payload_unit_start_indicator):
packetParser.skipBits(packetParser.readUnsignedByte() * 8)
packetParser.skipBits(12)
section_length = packetParser.readBits(12)
packetParser.skipBits(4 + 7 * 8)
program_info_length = packetParser.readBits(12)
packetParser.skipBytes( program_info_length )
bytesRemaining = section_length - 9 - program_info_length - 4
while (bytesRemaining > 0):
streamType = packetParser.readBits(8)
packetParser.skipBits(3)
elementaryPID = packetParser.readBits(13)
packetParser.skipBits(4)
ES_info_length = packetParser.readBits(12)
packetParser.skipBits(ES_info_length * 8)
bytesRemaining = bytesRemaining - ES_info_length - 5
#print "Track Id: {}, type: {}".format(elementaryPID, hex(streamType))
self.tracks[elementaryPID] = PESReader(elementaryPID, streamType)
self.pmtParsed = True