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 parses a DV input stream into DV frames to deliver to the downstream object |
19 | // C++ header |
20 | |
21 | #ifndef _DV_VIDEO_STREAM_FRAMER_HH |
22 | #define _DV_VIDEO_STREAM_FRAMER_HH |
23 | |
24 | #ifndef _FRAMED_FILTER_HH |
25 | #include "FramedFilter.hh" |
26 | #endif |
27 | |
28 | #define DV_DIF_BLOCK_SIZE 80 |
29 | #define DV_NUM_BLOCKS_PER_SEQUENCE 150 |
30 | #define DV_SAVED_INITIAL_BLOCKS_SIZE ((DV_NUM_BLOCKS_PER_SEQUENCE+6-1)*DV_DIF_BLOCK_SIZE) |
31 | /* enough data to ensure that it contains an intact 6-block header (which occurs at the start of a 150-block sequence) */ |
32 | |
33 | class DVVideoStreamFramer: public FramedFilter { |
34 | public: |
35 | static DVVideoStreamFramer* |
36 | createNew(UsageEnvironment& env, FramedSource* inputSource, |
37 | Boolean sourceIsSeekable = False, Boolean leavePresentationTimesUnmodified = False); |
38 | // Set "sourceIsSeekable" to True if the input source is a seekable object (e.g. a file), and the server that uses us |
39 | // does a seek-to-zero on the source before reading from it. (Our RTSP server implementation does this.) |
40 | char const* profileName(); |
41 | Boolean getFrameParameters(unsigned& frameSize/*bytes*/, double& frameDuration/*microseconds*/); |
42 | |
43 | protected: |
44 | DVVideoStreamFramer(UsageEnvironment& env, FramedSource* inputSource, |
45 | Boolean sourceIsSeekable, Boolean leavePresentationTimesUnmodified); |
46 | // called only by createNew(), or by subclass constructors |
47 | virtual ~DVVideoStreamFramer(); |
48 | |
49 | protected: |
50 | // redefined virtual functions: |
51 | virtual Boolean isDVVideoStreamFramer() const; |
52 | virtual void doGetNextFrame(); |
53 | |
54 | protected: |
55 | void getAndDeliverData(); // used to implement "doGetNextFrame()" |
56 | static void afterGettingFrame(void* clientData, unsigned frameSize, |
57 | unsigned numTruncatedBytes, |
58 | struct timeval presentationTime, |
59 | unsigned durationInMicroseconds); |
60 | void afterGettingFrame(unsigned frameSize, unsigned numTruncatedBytes, struct timeval presentationTime); |
61 | void getProfile(); |
62 | |
63 | protected: |
64 | Boolean fLeavePresentationTimesUnmodified; |
65 | void const* fOurProfile; |
66 | struct timeval fNextFramePresentationTime; |
67 | unsigned char fSavedInitialBlocks[DV_SAVED_INITIAL_BLOCKS_SIZE]; |
68 | char fInitialBlocksPresent; |
69 | Boolean fSourceIsSeekable; |
70 | }; |
71 | |
72 | #endif |
73 | |