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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 Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
8
 * 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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 * Libav 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
15
 * 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 Libav; 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

    
22
/**
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 * @file
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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"
29
#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"
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#include "libavutil/audioconvert.h"
34

    
35
#include "mpc.h"
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#include "mpcdata.h"
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#include "mpc8data.h"
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#include "mpc8huff.h"
39

    
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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;
42

    
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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 };
45

    
46
static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
47
{
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    int len = mpc8_cnk_len[k-1][n-1] - 1;
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    int code = len ? get_bits_long(gb, len) : 0;
50

    
51
    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];
53

    
54
    return code;
55
}
56

    
57
static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
58
{
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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);
62

    
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    do {
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        n--;
65
        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--;
70
        }
71
    } while(k > 0);
72

    
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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)
77
{
78
    if(mpc8_cnk_len[0][m] < 1) return 0;
79
    return mpc8_dec_base(gb, 1, m+1);
80
}
81

    
82
static int mpc8_get_mask(GetBitContext *gb, int size, int t)
83
{
84
    int mask = 0;
85

    
86
    if(t && t != size)
87
         mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
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    if((t << 1) > size) mask = ~mask;
89

    
90
    return mask;
91
}
92

    
93
static const uint16_t vlc_offsets[13] = {
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    0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
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};
96

    
97
static av_cold int mpc8_decode_init(AVCodecContext * avctx)
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{
99
    int i;
100
    MPCContext *c = avctx->priv_data;
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    GetBitContext gb;
102
    static int vlc_initialized = 0;
103
    int channels;
104

    
105
    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];
108
    static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
109
    static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
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    static VLC_TYPE dscf0_table[560][2];
111
    static VLC_TYPE dscf1_table[598][2];
112
    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];
115

    
116
    if(avctx->extradata_size < 2){
117
        av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
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        return -1;
119
    }
120
    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
121
    av_lfg_init(&c->rnd, 0xDEADBEEF);
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    dsputil_init(&c->dsp, avctx);
123

    
124
    ff_mpc_init();
125

    
126
    init_get_bits(&gb, avctx->extradata, 16);
127

    
128
    skip_bits(&gb, 3);//sample rate
129
    c->maxbands = get_bits(&gb, 5) + 1;
130
    channels = get_bits(&gb, 4) + 1;
131
    if (channels > 2) {
132
        av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
133
        return -1;
134
    }
135
    c->MSS = get_bits1(&gb);
136
    c->frames = 1 << (get_bits(&gb, 3) * 2);
137

    
138
    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
139
    avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
140

    
141
    if(vlc_initialized) return 0;
142
    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
143

    
144
    band_vlc.table = band_table;
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    band_vlc.table_allocated = 542;
146
    init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
147
             mpc8_bands_bits,  1, 1,
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             mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
149

    
150
    q1_vlc.table = q1_table;
151
    q1_vlc.table_allocated = 520;
152
    init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
153
             mpc8_q1_bits,  1, 1,
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             mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
155
    q9up_vlc.table = q9up_table;
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    q9up_vlc.table_allocated = 524;
157
    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);
160

    
161
    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,
164
             mpc8_scfi0_bits,  1, 1,
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             mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
166
    scfi_vlc[1].table = scfi1_table;
167
    scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
168
    init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
169
             mpc8_scfi1_bits,  1, 1,
170
             mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
171

    
172
    dscf_vlc[0].table = dscf0_table;
173
    dscf_vlc[0].table_allocated = 560;
174
    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);
177
    dscf_vlc[1].table = dscf1_table;
178
    dscf_vlc[1].table_allocated = 598;
179
    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);
182

    
183
    q3_vlc[0].table = q3_0_table;
184
    q3_vlc[0].table_allocated = 512;
185
    init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
186
             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);
189
    q3_vlc[1].table = q3_1_table;
190
    q3_vlc[1].table_allocated = 516;
191
    init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
192
             mpc8_q4_bits,  1, 1,
193
             mpc8_q4_codes, 1, 1,
194
             mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
195

    
196
    for(i = 0; i < 2; i++){
197
        res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
198
        res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
199
        init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
200
                 &mpc8_res_bits[i],  1, 1,
201
                 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
202

    
203
        q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
204
        q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
205
        init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
206
                 &mpc8_q2_bits[i],  1, 1,
207
                 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
208

    
209
        quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
210
        quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
211
        init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
212
                 &mpc8_q5_bits[i],  1, 1,
213
                 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
214
        quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
215
        quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
216
        init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
217
                 &mpc8_q6_bits[i],  1, 1,
218
                 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
219
        quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
220
        quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
221
        init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
222
                 &mpc8_q7_bits[i],  1, 1,
223
                 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
224
        quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
225
        quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
226
        init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
227
                 &mpc8_q8_bits[i],  1, 1,
228
                 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
229
    }
230
    vlc_initialized = 1;
231
    return 0;
232
}
233

    
234
static int mpc8_decode_frame(AVCodecContext * avctx,
235
                            void *data, int *data_size,
236
                            AVPacket *avpkt)
237
{
238
    const uint8_t *buf = avpkt->data;
239
    int buf_size = avpkt->size;
240
    MPCContext *c = avctx->priv_data;
241
    GetBitContext gb2, *gb = &gb2;
242
    int i, j, k, ch, cnt, res, t;
243
    Band *bands = c->bands;
244
    int off;
245
    int maxband, keyframe;
246
    int last[2];
247

    
248
    keyframe = c->cur_frame == 0;
249

    
250
    if(keyframe){
251
        memset(c->Q, 0, sizeof(c->Q));
252
        c->last_bits_used = 0;
253
    }
254
    init_get_bits(gb, buf, buf_size * 8);
255
    skip_bits(gb, c->last_bits_used & 7);
256

    
257
    if(keyframe)
258
        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
259
    else{
260
        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
261
        if(maxband > 32) maxband -= 33;
262
    }
263
    c->last_max_band = maxband;
264

    
265
    /* read subband indexes */
266
    if(maxband){
267
        last[0] = last[1] = 0;
268
        for(i = maxband - 1; i >= 0; i--){
269
            for(ch = 0; ch < 2; ch++){
270
                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
271
                if(last[ch] > 15) last[ch] -= 17;
272
                bands[i].res[ch] = last[ch];
273
            }
274
        }
275
        if(c->MSS){
276
            int mask;
277

    
278
            cnt = 0;
279
            for(i = 0; i < maxband; i++)
280
                if(bands[i].res[0] || bands[i].res[1])
281
                    cnt++;
282
            t = mpc8_get_mod_golomb(gb, cnt);
283
            mask = mpc8_get_mask(gb, cnt, t);
284
            for(i = maxband - 1; i >= 0; i--)
285
                if(bands[i].res[0] || bands[i].res[1]){
286
                    bands[i].msf = mask & 1;
287
                    mask >>= 1;
288
                }
289
        }
290
    }
291
    for(i = maxband; i < c->maxbands; i++)
292
        bands[i].res[0] = bands[i].res[1] = 0;
293

    
294
    if(keyframe){
295
        for(i = 0; i < 32; i++)
296
            c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
297
    }
298

    
299
    for(i = 0; i < maxband; i++){
300
        if(bands[i].res[0] || bands[i].res[1]){
301
            cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
302
            if(cnt >= 0){
303
                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
304
                if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
305
                if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
306
            }
307
        }
308
    }
309

    
310
    for(i = 0; i < maxband; i++){
311
        for(ch = 0; ch < 2; ch++){
312
            if(!bands[i].res[ch]) continue;
313

    
314
            if(c->oldDSCF[ch][i]){
315
                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
316
                c->oldDSCF[ch][i] = 0;
317
            }else{
318
                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
319
                if(t == 64)
320
                    t += get_bits(gb, 6);
321
                bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
322
            }
323
            for(j = 0; j < 2; j++){
324
                if((bands[i].scfi[ch] << j) & 2)
325
                    bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
326
                else{
327
                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
328
                    if(t == 31)
329
                        t = 64 + get_bits(gb, 6);
330
                    bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
331
                }
332
            }
333
        }
334
    }
335

    
336
    for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
337
        for(ch = 0; ch < 2; ch++){
338
            res = bands[i].res[ch];
339
            switch(res){
340
            case -1:
341
                for(j = 0; j < SAMPLES_PER_BAND; j++)
342
                    c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
343
                break;
344
            case 0:
345
                break;
346
            case 1:
347
                for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
348
                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
349
                    t = mpc8_get_mask(gb, 18, cnt);
350
                    for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
351
                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
352
                }
353
                break;
354
            case 2:
355
                cnt = 6;//2*mpc8_thres[res]
356
                for(j = 0; j < SAMPLES_PER_BAND; j += 3){
357
                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
358
                    c->Q[ch][off + j + 0] = mpc8_idx50[t];
359
                    c->Q[ch][off + j + 1] = mpc8_idx51[t];
360
                    c->Q[ch][off + j + 2] = mpc8_idx52[t];
361
                    cnt = (cnt >> 1) + mpc8_huffq2[t];
362
                }
363
                break;
364
            case 3:
365
            case 4:
366
                for(j = 0; j < SAMPLES_PER_BAND; j += 2){
367
                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
368
                    c->Q[ch][off + j + 1] = t >> 4;
369
                    c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
370
                }
371
                break;
372
            case 5:
373
            case 6:
374
            case 7:
375
            case 8:
376
                cnt = 2 * mpc8_thres[res];
377
                for(j = 0; j < SAMPLES_PER_BAND; j++){
378
                    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];
379
                    c->Q[ch][off + j] = t;
380
                    cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
381
                }
382
                break;
383
            default:
384
                for(j = 0; j < SAMPLES_PER_BAND; j++){
385
                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
386
                    if(res != 9){
387
                        c->Q[ch][off + j] <<= res - 9;
388
                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
389
                    }
390
                    c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
391
                }
392
            }
393
        }
394
    }
395

    
396
    ff_mpc_dequantize_and_synth(c, maxband, data, avctx->channels);
397

    
398
    c->cur_frame++;
399

    
400
    c->last_bits_used = get_bits_count(gb);
401
    if(c->cur_frame >= c->frames)
402
        c->cur_frame = 0;
403
    *data_size =  MPC_FRAME_SIZE * 2 * avctx->channels;
404

    
405
    return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
406
}
407

    
408
AVCodec ff_mpc8_decoder = {
409
    "mpc8",
410
    AVMEDIA_TYPE_AUDIO,
411
    CODEC_ID_MUSEPACK8,
412
    sizeof(MPCContext),
413
    mpc8_decode_init,
414
    NULL,
415
    NULL,
416
    mpc8_decode_frame,
417
    .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
418
};