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ffmpeg / libavcodec / mpc8.c @ 7d3829a8

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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,
13
 * 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
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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

    
34
#include "mpc.h"
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#include "mpcdata.h"
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#include "mpc8data.h"
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#include "mpc8huff.h"
38

    
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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 len = mpc8_cnk_len[k-1][n-1] - 1;
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    int code = len ? get_bits_long(gb, len) : 0;
49

    
50
    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];
52

    
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    return code;
54
}
55

    
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static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
57
{
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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);
61

    
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    do {
63
        n--;
64
        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);
71

    
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    return bits;
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}
74

    
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static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
76
{
77
    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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}
80

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

    
85
    if(t && t != size)
86
         mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
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    if((t << 1) > size) mask = ~mask;
88

    
89
    return mask;
90
}
91

    
92
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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};
95

    
96
static av_cold int mpc8_decode_init(AVCodecContext * avctx)
97
{
98
    int i;
99
    MPCContext *c = avctx->priv_data;
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    GetBitContext gb;
101
    static int vlc_initialized = 0;
102
    int channels;
103

    
104
    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];
112
    static VLC_TYPE q3_1_table[516][2];
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    static VLC_TYPE codes_table[5708][2];
114

    
115
    if(avctx->extradata_size < 2){
116
        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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    }
119
    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);
122

    
123
    ff_mpc_init();
124

    
125
    init_get_bits(&gb, avctx->extradata, 16);
126

    
127
    skip_bits(&gb, 3);//sample rate
128
    c->maxbands = get_bits(&gb, 5) + 1;
129
    channels = get_bits(&gb, 4) + 1;
130
    if (channels > 2) {
131
        av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
132
        return -1;
133
    }
134
    c->MSS = get_bits1(&gb);
135
    c->frames = 1 << (get_bits(&gb, 3) * 2);
136

    
137
    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
138
    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
139

    
140
    if(vlc_initialized) return 0;
141
    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
142

    
143
    band_vlc.table = band_table;
144
    band_vlc.table_allocated = 542;
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    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);
148

    
149
    q1_vlc.table = q1_table;
150
    q1_vlc.table_allocated = 520;
151
    init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
152
             mpc8_q1_bits,  1, 1,
153
             mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
154
    q9up_vlc.table = q9up_table;
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    q9up_vlc.table_allocated = 524;
156
    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);
159

    
160
    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,
163
             mpc8_scfi0_bits,  1, 1,
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             mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
165
    scfi_vlc[1].table = scfi1_table;
166
    scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
167
    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);
170

    
171
    dscf_vlc[0].table = dscf0_table;
172
    dscf_vlc[0].table_allocated = 560;
173
    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);
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    dscf_vlc[1].table = dscf1_table;
177
    dscf_vlc[1].table_allocated = 598;
178
    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);
181

    
182
    q3_vlc[0].table = q3_0_table;
183
    q3_vlc[0].table_allocated = 512;
184
    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);
188
    q3_vlc[1].table = q3_1_table;
189
    q3_vlc[1].table_allocated = 516;
190
    init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
191
             mpc8_q4_bits,  1, 1,
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             mpc8_q4_codes, 1, 1,
193
             mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
194

    
195
    for(i = 0; i < 2; i++){
196
        res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
197
        res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
198
        init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
199
                 &mpc8_res_bits[i],  1, 1,
200
                 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
201

    
202
        q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
203
        q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
204
        init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
205
                 &mpc8_q2_bits[i],  1, 1,
206
                 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
207

    
208
        quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
209
        quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
210
        init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
211
                 &mpc8_q5_bits[i],  1, 1,
212
                 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
213
        quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
214
        quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
215
        init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
216
                 &mpc8_q6_bits[i],  1, 1,
217
                 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
218
        quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
219
        quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
220
        init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
221
                 &mpc8_q7_bits[i],  1, 1,
222
                 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
223
        quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
224
        quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
225
        init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
226
                 &mpc8_q8_bits[i],  1, 1,
227
                 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
228
    }
229
    vlc_initialized = 1;
230
    return 0;
231
}
232

    
233
static int mpc8_decode_frame(AVCodecContext * avctx,
234
                            void *data, int *data_size,
235
                            AVPacket *avpkt)
236
{
237
    const uint8_t *buf = avpkt->data;
238
    int buf_size = avpkt->size;
239
    MPCContext *c = avctx->priv_data;
240
    GetBitContext gb2, *gb = &gb2;
241
    int i, j, k, ch, cnt, res, t;
242
    Band *bands = c->bands;
243
    int off;
244
    int maxband, keyframe;
245
    int last[2];
246

    
247
    keyframe = c->cur_frame == 0;
248

    
249
    if(keyframe){
250
        memset(c->Q, 0, sizeof(c->Q));
251
        c->last_bits_used = 0;
252
    }
253
    init_get_bits(gb, buf, buf_size * 8);
254
    skip_bits(gb, c->last_bits_used & 7);
255

    
256
    if(keyframe)
257
        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
258
    else{
259
        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
260
        if(maxband > 32) maxband -= 33;
261
    }
262
    c->last_max_band = maxband;
263

    
264
    /* read subband indexes */
265
    if(maxband){
266
        last[0] = last[1] = 0;
267
        for(i = maxband - 1; i >= 0; i--){
268
            for(ch = 0; ch < 2; ch++){
269
                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
270
                if(last[ch] > 15) last[ch] -= 17;
271
                bands[i].res[ch] = last[ch];
272
            }
273
        }
274
        if(c->MSS){
275
            int mask;
276

    
277
            cnt = 0;
278
            for(i = 0; i < maxband; i++)
279
                if(bands[i].res[0] || bands[i].res[1])
280
                    cnt++;
281
            t = mpc8_get_mod_golomb(gb, cnt);
282
            mask = mpc8_get_mask(gb, cnt, t);
283
            for(i = maxband - 1; i >= 0; i--)
284
                if(bands[i].res[0] || bands[i].res[1]){
285
                    bands[i].msf = mask & 1;
286
                    mask >>= 1;
287
                }
288
        }
289
    }
290
    for(i = maxband; i < c->maxbands; i++)
291
        bands[i].res[0] = bands[i].res[1] = 0;
292

    
293
    if(keyframe){
294
        for(i = 0; i < 32; i++)
295
            c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
296
    }
297

    
298
    for(i = 0; i < maxband; i++){
299
        if(bands[i].res[0] || bands[i].res[1]){
300
            cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
301
            if(cnt >= 0){
302
                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
303
                if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
304
                if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
305
            }
306
        }
307
    }
308

    
309
    for(i = 0; i < maxband; i++){
310
        for(ch = 0; ch < 2; ch++){
311
            if(!bands[i].res[ch]) continue;
312

    
313
            if(c->oldDSCF[ch][i]){
314
                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
315
                c->oldDSCF[ch][i] = 0;
316
            }else{
317
                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
318
                if(t == 64)
319
                    t += get_bits(gb, 6);
320
                bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
321
            }
322
            for(j = 0; j < 2; j++){
323
                if((bands[i].scfi[ch] << j) & 2)
324
                    bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
325
                else{
326
                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
327
                    if(t == 31)
328
                        t = 64 + get_bits(gb, 6);
329
                    bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
330
                }
331
            }
332
        }
333
    }
334

    
335
    for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
336
        for(ch = 0; ch < 2; ch++){
337
            res = bands[i].res[ch];
338
            switch(res){
339
            case -1:
340
                for(j = 0; j < SAMPLES_PER_BAND; j++)
341
                    c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
342
                break;
343
            case 0:
344
                break;
345
            case 1:
346
                for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
347
                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
348
                    t = mpc8_get_mask(gb, 18, cnt);
349
                    for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
350
                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
351
                }
352
                break;
353
            case 2:
354
                cnt = 6;//2*mpc8_thres[res]
355
                for(j = 0; j < SAMPLES_PER_BAND; j += 3){
356
                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
357
                    c->Q[ch][off + j + 0] = mpc8_idx50[t];
358
                    c->Q[ch][off + j + 1] = mpc8_idx51[t];
359
                    c->Q[ch][off + j + 2] = mpc8_idx52[t];
360
                    cnt = (cnt >> 1) + mpc8_huffq2[t];
361
                }
362
                break;
363
            case 3:
364
            case 4:
365
                for(j = 0; j < SAMPLES_PER_BAND; j += 2){
366
                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
367
                    c->Q[ch][off + j + 1] = t >> 4;
368
                    c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
369
                }
370
                break;
371
            case 5:
372
            case 6:
373
            case 7:
374
            case 8:
375
                cnt = 2 * mpc8_thres[res];
376
                for(j = 0; j < SAMPLES_PER_BAND; j++){
377
                    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];
378
                    c->Q[ch][off + j] = t;
379
                    cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
380
                }
381
                break;
382
            default:
383
                for(j = 0; j < SAMPLES_PER_BAND; j++){
384
                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
385
                    if(res != 9){
386
                        c->Q[ch][off + j] <<= res - 9;
387
                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
388
                    }
389
                    c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
390
                }
391
            }
392
        }
393
    }
394

    
395
    ff_mpc_dequantize_and_synth(c, maxband, data, avctx->channels);
396

    
397
    c->cur_frame++;
398

    
399
    c->last_bits_used = get_bits_count(gb);
400
    if(c->cur_frame >= c->frames)
401
        c->cur_frame = 0;
402
    *data_size =  MPC_FRAME_SIZE * 2 * avctx->channels;
403

    
404
    return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
405
}
406

    
407
AVCodec mpc8_decoder = {
408
    "mpc8",
409
    AVMEDIA_TYPE_AUDIO,
410
    CODEC_ID_MUSEPACK8,
411
    sizeof(MPCContext),
412
    mpc8_decode_init,
413
    NULL,
414
    NULL,
415
    mpc8_decode_frame,
416
    .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
417
};