2 * Musepack decoder core
3 * Copyright (c) 2006 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
24 * Musepack decoder core
25 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
26 * divided into 32 subbands.
32 #include "mpegaudio.h"
37 void ff_mpc_init(void)
39 ff_mpa_synth_init(ff_mpa_synth_window);
43 * Process decoded Musepack data and produce PCM
45 static void mpc_synth(MPCContext *c, int16_t *out)
49 OUT_INT samples[MPA_MAX_CHANNELS * MPA_FRAME_SIZE], *samples_ptr;
51 for(ch = 0; ch < 2; ch++){
52 samples_ptr = samples + ch;
53 for(i = 0; i < SAMPLES_PER_BAND; i++) {
54 ff_mpa_synth_filter(c->synth_buf[ch], &(c->synth_buf_offset[ch]),
55 ff_mpa_synth_window, &dither_state,
57 c->sb_samples[ch][i]);
61 for(i = 0; i < MPC_FRAME_SIZE*2; i++)
65 void ff_mpc_dequantize_and_synth(MPCContext * c, int maxband, void *data)
68 Band *bands = c->bands;
73 memset(c->sb_samples, 0, sizeof(c->sb_samples));
75 for(i = 0; i <= maxband; i++, off += SAMPLES_PER_BAND){
76 for(ch = 0; ch < 2; ch++){
79 mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][0]];
81 c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
82 mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][1]];
84 c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
85 mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][2]];
87 c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
92 for(j = 0; j < SAMPLES_PER_BAND; j++){
93 t1 = c->sb_samples[0][j][i];
94 t2 = c->sb_samples[1][j][i];
95 c->sb_samples[0][j][i] = t1 + t2;
96 c->sb_samples[1][j][i] = t1 - t2;