1 /* 2 * Musepack decoder 3 * Copyright (c) 2006 Konstantin Shishkov 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22 /** 23 * @file 24 * Musepack decoder 25 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples 26 * divided into 32 subbands. 27 */ 28 29 #ifndef AVCODEC_MPC_H 30 #define AVCODEC_MPC_H 31 32 #include "libavutil/lfg.h" 33 #include "libavutil/mem_internal.h" 34 35 #include "avcodec.h" 36 #include "bswapdsp.h" 37 #include "mpegaudio.h" 38 #include "mpegaudiodsp.h" 39 40 #define BANDS 32 41 #define SAMPLES_PER_BAND 36 42 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND) 43 44 /** Subband structure - hold all variables for each subband */ 45 typedef struct Band { 46 int msf; ///< mid-stereo flag 47 int res[2]; 48 int scfi[2]; 49 int scf_idx[2][3]; 50 int Q[2]; 51 }Band; 52 53 typedef struct MPCContext { 54 BswapDSPContext bdsp; 55 MPADSPContext mpadsp; 56 int IS, MSS, gapless; 57 int lastframelen; 58 int maxbands, last_max_band; 59 int last_bits_used; 60 int oldDSCF[2][BANDS]; 61 Band bands[BANDS]; 62 int Q[2][MPC_FRAME_SIZE]; 63 int cur_frame, frames; 64 uint8_t *bits; 65 int buf_size; 66 AVLFG rnd; 67 int frames_to_skip; 68 /* for synthesis */ 69 DECLARE_ALIGNED(16, MPA_INT, synth_buf)[MPA_MAX_CHANNELS][512*2]; 70 int synth_buf_offset[MPA_MAX_CHANNELS]; 71 DECLARE_ALIGNED(16, int32_t, sb_samples)[MPA_MAX_CHANNELS][36][SBLIMIT]; 72 } MPCContext; 73 74 void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels); 75 76 #endif /* AVCODEC_MPC_H */ 77