| /********** |
| This library is free software; you can redistribute it and/or modify it under |
| the terms of the GNU Lesser General Public License as published by the |
| Free Software Foundation; either version 2.1 of the License, or (at your |
| option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.) |
| |
| This library is distributed in the hope that it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for |
| more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with this library; if not, write to the Free Software Foundation, Inc., |
| 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| **********/ |
| // "liveMedia" |
| // Copyright (c) 1996-2015 Live Networks, Inc. All rights reserved. |
| // An abstract parser for MPEG video streams |
| // C++ header |
| |
| #ifndef _MPEG_VIDEO_STREAM_PARSER_HH |
| #define _MPEG_VIDEO_STREAM_PARSER_HH |
| |
| #ifndef _STREAM_PARSER_HH |
| #include "StreamParser.hh" |
| #endif |
| #ifndef _MPEG_VIDEO_STREAM_FRAMER_HH |
| #include "MPEGVideoStreamFramer.hh" |
| #endif |
| |
| ////////// MPEGVideoStreamParser definition ////////// |
| |
| class MPEGVideoStreamParser: public StreamParser { |
| public: |
| MPEGVideoStreamParser(MPEGVideoStreamFramer* usingSource, |
| FramedSource* inputSource); |
| virtual ~MPEGVideoStreamParser(); |
| |
| public: |
| void registerReadInterest(unsigned char* to, unsigned maxSize); |
| |
| virtual unsigned parse() = 0; |
| // returns the size of the frame that was acquired, or 0 if none was |
| // The number of truncated bytes (if any) is given by: |
| unsigned numTruncatedBytes() const; |
| |
| protected: |
| void setParseState(); |
| |
| // Record "byte" in the current output frame: |
| void saveByte(u_int8_t byte); |
| |
| void save4Bytes(u_int32_t word); |
| |
| // Save data until we see a sync word (0x000001xx): |
| void saveToNextCode(u_int32_t& curWord); |
| |
| // Skip data until we see a sync word (0x000001xx): |
| void skipToNextCode(u_int32_t& curWord); |
| |
| protected: |
| MPEGVideoStreamFramer* fUsingSource; |
| |
| // state of the frame that's currently being read: |
| unsigned char* fStartOfFrame; |
| unsigned char* fTo; |
| unsigned char* fLimit; |
| unsigned fNumTruncatedBytes; |
| unsigned curFrameSize(); |
| unsigned char* fSavedTo; |
| unsigned fSavedNumTruncatedBytes; |
| |
| private: // redefined virtual functions |
| virtual void restoreSavedParserState(); |
| }; |
| |
| #endif |