1 | /********** |
2 | This library is free software; you can redistribute it and/or modify it under |
3 | the terms of the GNU Lesser General Public License as published by the |
4 | Free Software Foundation; either version 3 of the License, or (at your |
5 | option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.) |
6 | |
7 | This library is distributed in the hope that it will be useful, but WITHOUT |
8 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
9 | FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for |
10 | more details. |
11 | |
12 | You should have received a copy of the GNU Lesser General Public License |
13 | along with this library; if not, write to the Free Software Foundation, Inc., |
14 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
15 | **********/ |
16 | // "liveMedia" |
17 | // Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved. |
18 | // A filter that breaks up an MPEG (1,2) audio elementary stream into frames |
19 | // C++ header |
20 | |
21 | #ifndef _MPEG_1OR2_AUDIO_STREAM_FRAMER_HH |
22 | #define _MPEG_1OR2_AUDIO_STREAM_FRAMER_HH |
23 | |
24 | #ifndef _FRAMED_FILTER_HH |
25 | #include "FramedFilter.hh" |
26 | #endif |
27 | |
28 | class MPEG1or2AudioStreamFramer: public FramedFilter { |
29 | public: |
30 | static MPEG1or2AudioStreamFramer* |
31 | createNew(UsageEnvironment& env, FramedSource* inputSource, |
32 | Boolean syncWithInputSource = False); |
33 | // If "syncWithInputSource" is True, the stream's presentation time |
34 | // will be reset to that of the input source, whenever new data |
35 | // is read from it. |
36 | |
37 | void flushInput(); // called if there is a discontinuity (seeking) in the input |
38 | |
39 | private: |
40 | MPEG1or2AudioStreamFramer(UsageEnvironment& env, FramedSource* inputSource, |
41 | Boolean syncWithInputSource); |
42 | // called only by createNew() |
43 | virtual ~MPEG1or2AudioStreamFramer(); |
44 | |
45 | static void continueReadProcessing(void* clientData, |
46 | unsigned char* ptr, unsigned size, |
47 | struct timeval presentationTime); |
48 | void continueReadProcessing(); |
49 | |
50 | void resetPresentationTime(struct timeval newPresentationTime); |
51 | // useful if we're being synced with a separate (e.g., video) stream |
52 | |
53 | private: |
54 | // redefined virtual functions: |
55 | virtual void doGetNextFrame(); |
56 | |
57 | private: |
58 | void reset(); |
59 | struct timeval currentFramePlayTime() const; |
60 | |
61 | private: |
62 | Boolean fSyncWithInputSource; |
63 | struct timeval fNextFramePresentationTime; |
64 | |
65 | private: // parsing state |
66 | class MPEG1or2AudioStreamParser* fParser; |
67 | friend class MPEG1or2AudioStreamParser; // hack |
68 | }; |
69 | |
70 | #endif |
71 | |