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1
/*
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 * Musepack SV8 decoder
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 * Copyright (c) 2007 Konstantin Shishkov
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21

    
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/**
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 * @file libavcodec/mpc8.c Musepack SV8 decoder
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 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
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 * divided into 32 subbands.
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 */
27

    
28
#include "libavutil/lfg.h"
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#include "avcodec.h"
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#include "get_bits.h"
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#include "dsputil.h"
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#include "mpegaudio.h"
33

    
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#include "mpc.h"
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#include "mpcdata.h"
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#include "mpc8data.h"
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#include "mpc8huff.h"
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static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
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static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
41

    
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static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
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static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
44

    
45
static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
46
{
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    int code = get_bits(gb, mpc8_cnk_len[k-1][n-1] - 1);
48

    
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    if (code >= mpc8_cnk_lost[k-1][n-1])
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        code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
51

    
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    return code;
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}
54

    
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static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
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{
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    int bits = 0;
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    const uint32_t * C = mpc8_cnk[k-1];
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    int code = mpc8_dec_base(gb, k, n);
60

    
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    do {
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        n--;
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        if (code >= C[n]) {
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            bits |= 1 << n;
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            code -= C[n];
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            C -= 32;
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            k--;
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        }
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    } while(k > 0);
70

    
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    return bits;
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}
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static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
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{
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    if(mpc8_cnk_len[0][m] < 1) return 0;
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    return mpc8_dec_base(gb, 1, m+1);
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}
79

    
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static int mpc8_get_mask(GetBitContext *gb, int size, int t)
81
{
82
    int mask = 0;
83

    
84
    if(t && t != size)
85
         mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
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    if((t << 1) > size) mask = ~mask;
87

    
88
    return mask;
89
}
90

    
91
static int vlc_offsets[13] = {
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    0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
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};
94

    
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static av_cold int mpc8_decode_init(AVCodecContext * avctx)
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{
97
    int i;
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    MPCContext *c = avctx->priv_data;
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    GetBitContext gb;
100
    static int vlc_initialized = 0;
101

    
102
    static VLC_TYPE band_table[542][2];
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    static VLC_TYPE q1_table[520][2];
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    static VLC_TYPE q9up_table[524][2];
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    static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
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    static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
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    static VLC_TYPE dscf0_table[560][2];
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    static VLC_TYPE dscf1_table[598][2];
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    static VLC_TYPE q3_0_table[512][2];
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    static VLC_TYPE q3_1_table[516][2];
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    static VLC_TYPE codes_table[5708][2];
112

    
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    if(avctx->extradata_size < 2){
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        av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
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        return -1;
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    }
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    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
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    av_lfg_init(&c->rnd, 0xDEADBEEF);
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    dsputil_init(&c->dsp, avctx);
120

    
121
    ff_mpc_init();
122

    
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    init_get_bits(&gb, avctx->extradata, 16);
124

    
125
    skip_bits(&gb, 3);//sample rate
126
    c->maxbands = get_bits(&gb, 5) + 1;
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    skip_bits(&gb, 4);//channels
128
    c->MSS = get_bits1(&gb);
129
    c->frames = 1 << (get_bits(&gb, 3) * 2);
130

    
131
    if(vlc_initialized) return 0;
132
    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
133

    
134
    band_vlc.table = band_table;
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    band_vlc.table_allocated = 542;
136
    init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
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             mpc8_bands_bits,  1, 1,
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             mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
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    q1_vlc.table = q1_table;
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    q1_vlc.table_allocated = 520;
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    init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
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             mpc8_q1_bits,  1, 1,
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             mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
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    q9up_vlc.table = q9up_table;
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    q9up_vlc.table_allocated = 524;
147
    init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
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             mpc8_q9up_bits,  1, 1,
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             mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
150

    
151
    scfi_vlc[0].table = scfi0_table;
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    scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
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    init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
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             mpc8_scfi0_bits,  1, 1,
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             mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
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    scfi_vlc[1].table = scfi1_table;
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    scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
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    init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
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             mpc8_scfi1_bits,  1, 1,
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             mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
161

    
162
    dscf_vlc[0].table = dscf0_table;
163
    dscf_vlc[0].table_allocated = 560;
164
    init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
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             mpc8_dscf0_bits,  1, 1,
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             mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
167
    dscf_vlc[1].table = dscf1_table;
168
    dscf_vlc[1].table_allocated = 598;
169
    init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
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             mpc8_dscf1_bits,  1, 1,
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             mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
172

    
173
    q3_vlc[0].table = q3_0_table;
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    q3_vlc[0].table_allocated = 512;
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    init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
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             mpc8_q3_bits,  1, 1,
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             mpc8_q3_codes, 1, 1,
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             mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
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    q3_vlc[1].table = q3_1_table;
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    q3_vlc[1].table_allocated = 516;
181
    init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
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             mpc8_q4_bits,  1, 1,
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             mpc8_q4_codes, 1, 1,
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             mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
185

    
186
    for(i = 0; i < 2; i++){
187
        res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
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        res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
189
        init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
190
                 &mpc8_res_bits[i],  1, 1,
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                 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
192

    
193
        q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
194
        q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
195
        init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
196
                 &mpc8_q2_bits[i],  1, 1,
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                 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
198

    
199
        quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
200
        quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
201
        init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
202
                 &mpc8_q5_bits[i],  1, 1,
203
                 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
204
        quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
205
        quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
206
        init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
207
                 &mpc8_q6_bits[i],  1, 1,
208
                 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
209
        quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
210
        quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
211
        init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
212
                 &mpc8_q7_bits[i],  1, 1,
213
                 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
214
        quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
215
        quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
216
        init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
217
                 &mpc8_q8_bits[i],  1, 1,
218
                 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
219
    }
220
    vlc_initialized = 1;
221
    avctx->sample_fmt = SAMPLE_FMT_S16;
222
    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
223
    return 0;
224
}
225

    
226
static int mpc8_decode_frame(AVCodecContext * avctx,
227
                            void *data, int *data_size,
228
                            AVPacket *avpkt)
229
{
230
    const uint8_t *buf = avpkt->data;
231
    int buf_size = avpkt->size;
232
    MPCContext *c = avctx->priv_data;
233
    GetBitContext gb2, *gb = &gb2;
234
    int i, j, k, ch, cnt, res, t;
235
    Band *bands = c->bands;
236
    int off;
237
    int maxband, keyframe;
238
    int last[2];
239

    
240
    keyframe = c->cur_frame == 0;
241

    
242
    if(keyframe){
243
        memset(c->Q, 0, sizeof(c->Q));
244
        c->last_bits_used = 0;
245
    }
246
    init_get_bits(gb, buf, buf_size * 8);
247
    skip_bits(gb, c->last_bits_used & 7);
248

    
249
    if(keyframe)
250
        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
251
    else{
252
        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
253
        if(maxband > 32) maxband -= 33;
254
    }
255
    c->last_max_band = maxband;
256

    
257
    /* read subband indexes */
258
    if(maxband){
259
        last[0] = last[1] = 0;
260
        for(i = maxband - 1; i >= 0; i--){
261
            for(ch = 0; ch < 2; ch++){
262
                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
263
                if(last[ch] > 15) last[ch] -= 17;
264
                bands[i].res[ch] = last[ch];
265
            }
266
        }
267
        if(c->MSS){
268
            int mask;
269

    
270
            cnt = 0;
271
            for(i = 0; i < maxband; i++)
272
                if(bands[i].res[0] || bands[i].res[1])
273
                    cnt++;
274
            t = mpc8_get_mod_golomb(gb, cnt);
275
            mask = mpc8_get_mask(gb, cnt, t);
276
            for(i = maxband - 1; i >= 0; i--)
277
                if(bands[i].res[0] || bands[i].res[1]){
278
                    bands[i].msf = mask & 1;
279
                    mask >>= 1;
280
                }
281
        }
282
    }
283
    for(i = maxband; i < c->maxbands; i++)
284
        bands[i].res[0] = bands[i].res[1] = 0;
285

    
286
    if(keyframe){
287
        for(i = 0; i < 32; i++)
288
            c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
289
    }
290

    
291
    for(i = 0; i < maxband; i++){
292
        if(bands[i].res[0] || bands[i].res[1]){
293
            cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
294
            if(cnt >= 0){
295
                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
296
                if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
297
                if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
298
            }
299
        }
300
    }
301

    
302
    for(i = 0; i < maxband; i++){
303
        for(ch = 0; ch < 2; ch++){
304
            if(!bands[i].res[ch]) continue;
305

    
306
            if(c->oldDSCF[ch][i]){
307
                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
308
                c->oldDSCF[ch][i] = 0;
309
            }else{
310
                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
311
                if(t == 64)
312
                    t += get_bits(gb, 6);
313
                bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
314
            }
315
            for(j = 0; j < 2; j++){
316
                if((bands[i].scfi[ch] << j) & 2)
317
                    bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
318
                else{
319
                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
320
                    if(t == 31)
321
                        t = 64 + get_bits(gb, 6);
322
                    bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
323
                }
324
            }
325
        }
326
    }
327

    
328
    for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
329
        for(ch = 0; ch < 2; ch++){
330
            res = bands[i].res[ch];
331
            switch(res){
332
            case -1:
333
                for(j = 0; j < SAMPLES_PER_BAND; j++)
334
                    c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
335
                break;
336
            case 0:
337
                break;
338
            case 1:
339
                for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
340
                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
341
                    t = mpc8_get_mask(gb, 18, cnt);
342
                    for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
343
                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
344
                }
345
                break;
346
            case 2:
347
                cnt = 6;//2*mpc8_thres[res]
348
                for(j = 0; j < SAMPLES_PER_BAND; j += 3){
349
                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
350
                    c->Q[ch][off + j + 0] = mpc8_idx50[t];
351
                    c->Q[ch][off + j + 1] = mpc8_idx51[t];
352
                    c->Q[ch][off + j + 2] = mpc8_idx52[t];
353
                    cnt = (cnt >> 1) + mpc8_huffq2[t];
354
                }
355
                break;
356
            case 3:
357
            case 4:
358
                for(j = 0; j < SAMPLES_PER_BAND; j += 2){
359
                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
360
                    c->Q[ch][off + j + 1] = t >> 4;
361
                    c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
362
                }
363
                break;
364
            case 5:
365
            case 6:
366
            case 7:
367
            case 8:
368
                cnt = 2 * mpc8_thres[res];
369
                for(j = 0; j < SAMPLES_PER_BAND; j++){
370
                    t = get_vlc2(gb, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
371
                    c->Q[ch][off + j] = t;
372
                    cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
373
                }
374
                break;
375
            default:
376
                for(j = 0; j < SAMPLES_PER_BAND; j++){
377
                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
378
                    if(res != 9){
379
                        c->Q[ch][off + j] <<= res - 9;
380
                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
381
                    }
382
                    c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
383
                }
384
            }
385
        }
386
    }
387

    
388
    ff_mpc_dequantize_and_synth(c, maxband, data);
389

    
390
    c->cur_frame++;
391

    
392
    c->last_bits_used = get_bits_count(gb);
393
    if(c->cur_frame >= c->frames)
394
        c->cur_frame = 0;
395
    *data_size =  MPC_FRAME_SIZE * 4;
396

    
397
    return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
398
}
399

    
400
AVCodec mpc8_decoder = {
401
    "mpc8",
402
    CODEC_TYPE_AUDIO,
403
    CODEC_ID_MUSEPACK8,
404
    sizeof(MPCContext),
405
    mpc8_decode_init,
406
    NULL,
407
    NULL,
408
    mpc8_decode_frame,
409
    .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
410
};