| /********** |
| 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 3 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) 1996-2020 Live Networks, Inc. All rights reserved. |
| // MP3 internal implementation details (Huffman encoding) |
| // C++ header |
| |
| #ifndef _MP3_INTERNALS_HUFFMAN_HH |
| #define _MP3_INTERNALS_HUFFMAN_HH |
| |
| #ifndef _MP3_INTERNALS_HH |
| #include "MP3Internals.hh" |
| #endif |
| |
| void updateSideInfoForHuffman(MP3SideInfo& sideInfo, Boolean isMPEG2, |
| unsigned char const* mainDataPtr, |
| unsigned p23L0, unsigned p23L1, |
| unsigned& part23Length0a, |
| unsigned& part23Length0aTruncation, |
| unsigned& part23Length0b, |
| unsigned& part23Length0bTruncation, |
| unsigned& part23Length1a, |
| unsigned& part23Length1aTruncation, |
| unsigned& part23Length1b, |
| unsigned& part23Length1bTruncation); |
| |
| #define SSLIMIT 18 |
| |
| class MP3HuffmanEncodingInfo { |
| public: |
| MP3HuffmanEncodingInfo(Boolean includeDecodedValues = False); |
| ~MP3HuffmanEncodingInfo(); |
| |
| public: |
| unsigned numSamples; |
| unsigned allBitOffsets[SBLIMIT*SSLIMIT + 1]; |
| unsigned reg1Start, reg2Start, bigvalStart; /* special bit offsets */ |
| unsigned* decodedValues; |
| }; |
| |
| /* forward */ |
| void MP3HuffmanDecode(MP3SideInfo::gr_info_s_t* gr, Boolean isMPEG2, |
| unsigned char const* fromBasePtr, |
| unsigned fromBitOffset, unsigned fromLength, |
| unsigned& scaleFactorsLength, |
| MP3HuffmanEncodingInfo& hei); |
| |
| extern unsigned char huffdec[]; // huffman table data |
| |
| // The following are used if we process Huffman-decoded values |
| #ifdef FOUR_BYTE_SAMPLES |
| #define BYTES_PER_SAMPLE_VALUE 4 |
| #else |
| #ifdef TWO_BYTE_SAMPLES |
| #define BYTES_PER_SAMPLE_VALUE 2 |
| #else |
| // ONE_BYTE_SAMPLES |
| #define BYTES_PER_SAMPLE_VALUE 1 |
| #endif |
| #endif |
| |
| #ifdef DO_HUFFMAN_ENCODING |
| unsigned MP3HuffmanEncode(MP3SideInfo::gr_info_s_t const* gr, |
| unsigned char const* fromPtr, |
| unsigned char* toPtr, unsigned toBitOffset, |
| unsigned numHuffBits); |
| #endif |
| |
| #endif |
