| 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 | |