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ffmpeg / libavcodec / mpc8.c @ 5d6e4c16

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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
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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 * 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

    
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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"
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 };
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45
static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
46
{
47
    int len = mpc8_cnk_len[k-1][n-1] - 1;
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    int code = len ? get_bits_long(gb, len) : 0;
49

    
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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];
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
{
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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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}
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

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

    
103
    static VLC_TYPE band_table[542][2];
104
    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];
112
    static VLC_TYPE codes_table[5708][2];
113

    
114
    if(avctx->extradata_size < 2){
115
        av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
116
        return -1;
117
    }
118
    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
119
    av_lfg_init(&c->rnd, 0xDEADBEEF);
120
    dsputil_init(&c->dsp, avctx);
121

    
122
    ff_mpc_init();
123

    
124
    init_get_bits(&gb, avctx->extradata, 16);
125

    
126
    skip_bits(&gb, 3);//sample rate
127
    c->maxbands = get_bits(&gb, 5) + 1;
128
    skip_bits(&gb, 4);//channels
129
    c->MSS = get_bits1(&gb);
130
    c->frames = 1 << (get_bits(&gb, 3) * 2);
131

    
132
    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
133
    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
134

    
135
    if(vlc_initialized) return 0;
136
    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
137

    
138
    band_vlc.table = band_table;
139
    band_vlc.table_allocated = 542;
140
    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);
143

    
144
    q1_vlc.table = q1_table;
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    q1_vlc.table_allocated = 520;
146
    init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
147
             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;
151
    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);
154

    
155
    scfi_vlc[0].table = scfi0_table;
156
    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;
162
    init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
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             mpc8_scfi1_bits,  1, 1,
164
             mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
165

    
166
    dscf_vlc[0].table = dscf0_table;
167
    dscf_vlc[0].table_allocated = 560;
168
    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;
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    dscf_vlc[1].table_allocated = 598;
173
    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);
176

    
177
    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;
184
    q3_vlc[1].table_allocated = 516;
185
    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);
189

    
190
    for(i = 0; i < 2; i++){
191
        res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
192
        res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
193
        init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
194
                 &mpc8_res_bits[i],  1, 1,
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                 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
196

    
197
        q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
198
        q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
199
        init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
200
                 &mpc8_q2_bits[i],  1, 1,
201
                 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
202

    
203
        quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
204
        quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
205
        init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
206
                 &mpc8_q5_bits[i],  1, 1,
207
                 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
208
        quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
209
        quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
210
        init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
211
                 &mpc8_q6_bits[i],  1, 1,
212
                 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
213
        quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
214
        quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
215
        init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
216
                 &mpc8_q7_bits[i],  1, 1,
217
                 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
218
        quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
219
        quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
220
        init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
221
                 &mpc8_q8_bits[i],  1, 1,
222
                 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
223
    }
224
    vlc_initialized = 1;
225
    return 0;
226
}
227

    
228
static int mpc8_decode_frame(AVCodecContext * avctx,
229
                            void *data, int *data_size,
230
                            AVPacket *avpkt)
231
{
232
    const uint8_t *buf = avpkt->data;
233
    int buf_size = avpkt->size;
234
    MPCContext *c = avctx->priv_data;
235
    GetBitContext gb2, *gb = &gb2;
236
    int i, j, k, ch, cnt, res, t;
237
    Band *bands = c->bands;
238
    int off;
239
    int maxband, keyframe;
240
    int last[2];
241

    
242
    keyframe = c->cur_frame == 0;
243

    
244
    if(keyframe){
245
        memset(c->Q, 0, sizeof(c->Q));
246
        c->last_bits_used = 0;
247
    }
248
    init_get_bits(gb, buf, buf_size * 8);
249
    skip_bits(gb, c->last_bits_used & 7);
250

    
251
    if(keyframe)
252
        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
253
    else{
254
        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
255
        if(maxband > 32) maxband -= 33;
256
    }
257
    c->last_max_band = maxband;
258

    
259
    /* read subband indexes */
260
    if(maxband){
261
        last[0] = last[1] = 0;
262
        for(i = maxband - 1; i >= 0; i--){
263
            for(ch = 0; ch < 2; ch++){
264
                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
265
                if(last[ch] > 15) last[ch] -= 17;
266
                bands[i].res[ch] = last[ch];
267
            }
268
        }
269
        if(c->MSS){
270
            int mask;
271

    
272
            cnt = 0;
273
            for(i = 0; i < maxband; i++)
274
                if(bands[i].res[0] || bands[i].res[1])
275
                    cnt++;
276
            t = mpc8_get_mod_golomb(gb, cnt);
277
            mask = mpc8_get_mask(gb, cnt, t);
278
            for(i = maxband - 1; i >= 0; i--)
279
                if(bands[i].res[0] || bands[i].res[1]){
280
                    bands[i].msf = mask & 1;
281
                    mask >>= 1;
282
                }
283
        }
284
    }
285
    for(i = maxband; i < c->maxbands; i++)
286
        bands[i].res[0] = bands[i].res[1] = 0;
287

    
288
    if(keyframe){
289
        for(i = 0; i < 32; i++)
290
            c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
291
    }
292

    
293
    for(i = 0; i < maxband; i++){
294
        if(bands[i].res[0] || bands[i].res[1]){
295
            cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
296
            if(cnt >= 0){
297
                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
298
                if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
299
                if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
300
            }
301
        }
302
    }
303

    
304
    for(i = 0; i < maxband; i++){
305
        for(ch = 0; ch < 2; ch++){
306
            if(!bands[i].res[ch]) continue;
307

    
308
            if(c->oldDSCF[ch][i]){
309
                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
310
                c->oldDSCF[ch][i] = 0;
311
            }else{
312
                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
313
                if(t == 64)
314
                    t += get_bits(gb, 6);
315
                bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
316
            }
317
            for(j = 0; j < 2; j++){
318
                if((bands[i].scfi[ch] << j) & 2)
319
                    bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
320
                else{
321
                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
322
                    if(t == 31)
323
                        t = 64 + get_bits(gb, 6);
324
                    bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
325
                }
326
            }
327
        }
328
    }
329

    
330
    for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
331
        for(ch = 0; ch < 2; ch++){
332
            res = bands[i].res[ch];
333
            switch(res){
334
            case -1:
335
                for(j = 0; j < SAMPLES_PER_BAND; j++)
336
                    c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
337
                break;
338
            case 0:
339
                break;
340
            case 1:
341
                for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
342
                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
343
                    t = mpc8_get_mask(gb, 18, cnt);
344
                    for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
345
                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
346
                }
347
                break;
348
            case 2:
349
                cnt = 6;//2*mpc8_thres[res]
350
                for(j = 0; j < SAMPLES_PER_BAND; j += 3){
351
                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
352
                    c->Q[ch][off + j + 0] = mpc8_idx50[t];
353
                    c->Q[ch][off + j + 1] = mpc8_idx51[t];
354
                    c->Q[ch][off + j + 2] = mpc8_idx52[t];
355
                    cnt = (cnt >> 1) + mpc8_huffq2[t];
356
                }
357
                break;
358
            case 3:
359
            case 4:
360
                for(j = 0; j < SAMPLES_PER_BAND; j += 2){
361
                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
362
                    c->Q[ch][off + j + 1] = t >> 4;
363
                    c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
364
                }
365
                break;
366
            case 5:
367
            case 6:
368
            case 7:
369
            case 8:
370
                cnt = 2 * mpc8_thres[res];
371
                for(j = 0; j < SAMPLES_PER_BAND; j++){
372
                    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];
373
                    c->Q[ch][off + j] = t;
374
                    cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
375
                }
376
                break;
377
            default:
378
                for(j = 0; j < SAMPLES_PER_BAND; j++){
379
                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
380
                    if(res != 9){
381
                        c->Q[ch][off + j] <<= res - 9;
382
                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
383
                    }
384
                    c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
385
                }
386
            }
387
        }
388
    }
389

    
390
    ff_mpc_dequantize_and_synth(c, maxband, data);
391

    
392
    c->cur_frame++;
393

    
394
    c->last_bits_used = get_bits_count(gb);
395
    if(c->cur_frame >= c->frames)
396
        c->cur_frame = 0;
397
    *data_size =  MPC_FRAME_SIZE * 4;
398

    
399
    return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
400
}
401

    
402
AVCodec mpc8_decoder = {
403
    "mpc8",
404
    AVMEDIA_TYPE_AUDIO,
405
    CODEC_ID_MUSEPACK8,
406
    sizeof(MPCContext),
407
    mpc8_decode_init,
408
    NULL,
409
    NULL,
410
    mpc8_decode_frame,
411
    .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
412
};