1/**********
2This library is free software; you can redistribute it and/or modify it under
3the terms of the GNU Lesser General Public License as published by the
4Free Software Foundation; either version 3 of the License, or (at your
5option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)
6
7This library is distributed in the hope that it will be useful, but WITHOUT
8ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
9FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
10more details.
11
12You should have received a copy of the GNU Lesser General Public License
13along with this library; if not, write to the Free Software Foundation, Inc.,
1451 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
15**********/
16// "liveMedia"
17// Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved.// A filter that converts a MPEG Transport Stream file - with corresponding index file
18// - to a corresponding Video Elementary Stream. It also uses a "scale" parameter
19// to implement 'trick mode' (fast forward or reverse play, using I-frames) on
20// the video stream.
21// C++ header
22
23#ifndef _MPEG2_TRANSPORT_STREAM_TRICK_MODE_FILTER_HH
24#define _MPEG2_TRANSPORT_STREAM_TRICK_MODE_FILTER_HH
25
26#ifndef _FRAMED_FILTER_HH
27#include "FramedFilter.hh"
28#endif
29
30#ifndef _MPEG2_TRANSPORT_STREAM_INDEX_FILE_HH
31#include "MPEG2TransportStreamIndexFile.hh"
32#endif
33
34#ifndef TRANSPORT_PACKET_SIZE
35#define TRANSPORT_PACKET_SIZE 188
36#endif
37
38class MPEG2TransportStreamTrickModeFilter: public FramedFilter {
39public:
40 static MPEG2TransportStreamTrickModeFilter*
41 createNew(UsageEnvironment& env, FramedSource* inputSource,
42 MPEG2TransportStreamIndexFile* indexFile, int scale);
43
44 Boolean seekTo(unsigned long tsPacketNumber, unsigned long indexRecordNumber);
45
46 unsigned long nextIndexRecordNum() const { return fNextIndexRecordNum; }
47
48 void forgetInputSource() { fInputSource = NULL; }
49 // this lets us delete this without also deleting the input Transport Stream
50
51protected:
52 MPEG2TransportStreamTrickModeFilter(UsageEnvironment& env, FramedSource* inputSource,
53 MPEG2TransportStreamIndexFile* indexFile, int scale);
54 // called only by createNew()
55 virtual ~MPEG2TransportStreamTrickModeFilter();
56
57private:
58 // Redefined virtual functions:
59 virtual void doGetNextFrame();
60 virtual void doStopGettingFrames();
61
62private:
63 void attemptDeliveryToClient();
64 void seekToTransportPacket(unsigned long tsPacketNum);
65 void readTransportPacket(unsigned long tsPacketNum); // asynchronously
66
67 static void afterGettingFrame(void* clientData, unsigned frameSize,
68 unsigned numTruncatedBytes,
69 struct timeval presentationTime,
70 unsigned durationInMicroseconds);
71 void afterGettingFrame1(unsigned frameSize);
72
73 static void onSourceClosure(void* clientData);
74 void onSourceClosure1();
75
76private:
77 Boolean fHaveStarted;
78 MPEG2TransportStreamIndexFile* fIndexFile;
79 int fScale; // absolute value
80 int fDirection; // 1 => forward; -1 => reverse
81 enum {
82 SKIPPING_FRAME,
83 DELIVERING_SAVED_FRAME,
84 SAVING_AND_DELIVERING_FRAME
85 } fState;
86 unsigned fFrameCount;
87 unsigned long fNextIndexRecordNum; // next to be read from the index file
88 unsigned long fNextTSPacketNum; // next to be read from the transport stream file
89 unsigned char fInputBuffer[TRANSPORT_PACKET_SIZE];
90 unsigned long fCurrentTSPacketNum; // corresponding to data currently in the buffer
91 unsigned long fDesiredTSPacketNum;
92 u_int8_t fDesiredDataOffset, fDesiredDataSize;
93 float fDesiredDataPCR, fFirstPCR;
94 unsigned long fSavedFrameIndexRecordStart;
95 unsigned long fSavedSequentialIndexRecordNum;
96 Boolean fUseSavedFrameNextTime;
97};
98
99#endif
100