GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/atrac1.c Lines: 123 138 89.1 %
Date: 2019-11-18 18:00:01 Branches: 53 68 77.9 %

Line Branch Exec Source
1
/*
2
 * ATRAC1 compatible decoder
3
 * Copyright (c) 2009 Maxim Poliakovski
4
 * Copyright (c) 2009 Benjamin Larsson
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 *
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 * This file is part of FFmpeg.
7
 *
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 * FFmpeg is free software; you can redistribute it and/or
9
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
11
 * 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,
14
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16
 * Lesser General Public License for more details.
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 *
18
 * 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
21
 */
22
23
/**
24
 * @file
25
 * ATRAC1 compatible decoder.
26
 * This decoder handles raw ATRAC1 data and probably SDDS data.
27
 */
28
29
/* Many thanks to Tim Craig for all the help! */
30
31
#include <math.h>
32
#include <stddef.h>
33
#include <stdio.h>
34
35
#include "libavutil/float_dsp.h"
36
#include "avcodec.h"
37
#include "get_bits.h"
38
#include "fft.h"
39
#include "internal.h"
40
#include "sinewin.h"
41
42
#include "atrac.h"
43
#include "atrac1data.h"
44
45
#define AT1_MAX_BFU      52                 ///< max number of block floating units in a sound unit
46
#define AT1_SU_SIZE      212                ///< number of bytes in a sound unit
47
#define AT1_SU_SAMPLES   512                ///< number of samples in a sound unit
48
#define AT1_FRAME_SIZE   AT1_SU_SIZE * 2
49
#define AT1_SU_MAX_BITS  AT1_SU_SIZE * 8
50
#define AT1_MAX_CHANNELS 2
51
52
#define AT1_QMF_BANDS    3
53
#define IDX_LOW_BAND     0
54
#define IDX_MID_BAND     1
55
#define IDX_HIGH_BAND    2
56
57
/**
58
 * Sound unit struct, one unit is used per channel
59
 */
60
typedef struct AT1SUCtx {
61
    int                 log2_block_count[AT1_QMF_BANDS];    ///< log2 number of blocks in a band
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    int                 num_bfus;                           ///< number of Block Floating Units
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    float*              spectrum[2];
64
    DECLARE_ALIGNED(32, float, spec1)[AT1_SU_SAMPLES];     ///< mdct buffer
65
    DECLARE_ALIGNED(32, float, spec2)[AT1_SU_SAMPLES];     ///< mdct buffer
66
    DECLARE_ALIGNED(32, float, fst_qmf_delay)[46];         ///< delay line for the 1st stacked QMF filter
67
    DECLARE_ALIGNED(32, float, snd_qmf_delay)[46];         ///< delay line for the 2nd stacked QMF filter
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    DECLARE_ALIGNED(32, float, last_qmf_delay)[256+39];    ///< delay line for the last stacked QMF filter
69
} AT1SUCtx;
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/**
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 * The atrac1 context, holds all needed parameters for decoding
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 */
74
typedef struct AT1Ctx {
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    AT1SUCtx            SUs[AT1_MAX_CHANNELS];              ///< channel sound unit
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    DECLARE_ALIGNED(32, float, spec)[AT1_SU_SAMPLES];      ///< the mdct spectrum buffer
77
78
    DECLARE_ALIGNED(32, float,  low)[256];
79
    DECLARE_ALIGNED(32, float,  mid)[256];
80
    DECLARE_ALIGNED(32, float, high)[512];
81
    float*              bands[3];
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    FFTContext          mdct_ctx[3];
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    AVFloatDSPContext   *fdsp;
84
} AT1Ctx;
85
86
/** size of the transform in samples in the long mode for each QMF band */
87
static const uint16_t samples_per_band[3] = {128, 128, 256};
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static const uint8_t   mdct_long_nbits[3] = {7, 7, 8};
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7157
static void at1_imdct(AT1Ctx *q, float *spec, float *out, int nbits,
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                      int rev_spec)
93
{
94
7157
    FFTContext* mdct_context = &q->mdct_ctx[nbits - 5 - (nbits > 6)];
95
7157
    int transf_size = 1 << nbits;
96
97
7157
    if (rev_spec) {
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        int i;
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459048
        for (i = 0; i < transf_size / 2; i++)
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454272
            FFSWAP(float, spec[i], spec[transf_size - 1 - i]);
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    }
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7157
    mdct_context->imdct_half(mdct_context, out, spec);
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7157
}
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2366
static int at1_imdct_block(AT1SUCtx* su, AT1Ctx *q)
107
{
108
    int          band_num, band_samples, log2_block_count, nbits, num_blocks, block_size;
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2366
    unsigned int start_pos, ref_pos = 0, pos = 0;
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111
9464
    for (band_num = 0; band_num < AT1_QMF_BANDS; band_num++) {
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        float *prev_buf;
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        int j;
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7098
        band_samples = samples_per_band[band_num];
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7098
        log2_block_count = su->log2_block_count[band_num];
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        /* number of mdct blocks in the current QMF band: 1 - for long mode */
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        /* 4 for short mode(low/middle bands) and 8 for short mode(high band)*/
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7098
        num_blocks = 1 << log2_block_count;
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122
7098
        if (num_blocks == 1) {
123
            /* mdct block size in samples: 128 (long mode, low & mid bands), */
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            /* 256 (long mode, high band) and 32 (short mode, all bands) */
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7085
            block_size = band_samples >> log2_block_count;
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127
            /* calc transform size in bits according to the block_size_mode */
128
7085
            nbits = mdct_long_nbits[band_num] - log2_block_count;
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130

7085
            if (nbits != 5 && nbits != 7 && nbits != 8)
131
                return AVERROR_INVALIDDATA;
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        } else {
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13
            block_size = 32;
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13
            nbits = 5;
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        }
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7098
        start_pos = 0;
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7098
        prev_buf = &su->spectrum[1][ref_pos + band_samples - 16];
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14255
        for (j=0; j < num_blocks; j++) {
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7157
            at1_imdct(q, &q->spec[pos], &su->spectrum[0][ref_pos + start_pos], nbits, band_num);
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            /* overlap and window */
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7157
            q->fdsp->vector_fmul_window(&q->bands[band_num][start_pos], prev_buf,
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7157
                                       &su->spectrum[0][ref_pos + start_pos], ff_sine_32, 16);
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7157
            prev_buf = &su->spectrum[0][ref_pos+start_pos + 16];
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7157
            start_pos += block_size;
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7157
            pos += block_size;
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        }
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151
7098
        if (num_blocks == 1)
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7085
            memcpy(q->bands[band_num] + 32, &su->spectrum[0][ref_pos + 16], 240 * sizeof(float));
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154
7098
        ref_pos += band_samples;
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    }
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157
    /* Swap buffers so the mdct overlap works */
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2366
    FFSWAP(float*, su->spectrum[0], su->spectrum[1]);
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160
2366
    return 0;
161
}
162
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/**
164
 * Parse the block size mode byte
165
 */
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2366
static int at1_parse_bsm(GetBitContext* gb, int log2_block_cnt[AT1_QMF_BANDS])
168
{
169
    int log2_block_count_tmp, i;
170
171
7098
    for (i = 0; i < 2; i++) {
172
        /* low and mid band */
173
4732
        log2_block_count_tmp = get_bits(gb, 2);
174
4732
        if (log2_block_count_tmp & 1)
175
            return AVERROR_INVALIDDATA;
176
4732
        log2_block_cnt[i] = 2 - log2_block_count_tmp;
177
    }
178
179
    /* high band */
180
2366
    log2_block_count_tmp = get_bits(gb, 2);
181

2366
    if (log2_block_count_tmp != 0 && log2_block_count_tmp != 3)
182
        return AVERROR_INVALIDDATA;
183
2366
    log2_block_cnt[IDX_HIGH_BAND] = 3 - log2_block_count_tmp;
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185
2366
    skip_bits(gb, 2);
186
2366
    return 0;
187
}
188
189
190
2366
static int at1_unpack_dequant(GetBitContext* gb, AT1SUCtx* su,
191
                              float spec[AT1_SU_SAMPLES])
192
{
193
    int bits_used, band_num, bfu_num, i;
194
    uint8_t idwls[AT1_MAX_BFU];                 ///< the word length indexes for each BFU
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    uint8_t idsfs[AT1_MAX_BFU];                 ///< the scalefactor indexes for each BFU
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197
    /* parse the info byte (2nd byte) telling how much BFUs were coded */
198
2366
    su->num_bfus = bfu_amount_tab1[get_bits(gb, 3)];
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200
    /* calc number of consumed bits:
201
        num_BFUs * (idwl(4bits) + idsf(6bits)) + log2_block_count(8bits) + info_byte(8bits)
202
        + info_byte_copy(8bits) + log2_block_count_copy(8bits) */
203
7098
    bits_used = su->num_bfus * 10 + 32 +
204
2366
                bfu_amount_tab2[get_bits(gb, 2)] +
205
2366
                (bfu_amount_tab3[get_bits(gb, 3)] << 1);
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207
    /* get word length index (idwl) for each BFU */
208
107674
    for (i = 0; i < su->num_bfus; i++)
209
105308
        idwls[i] = get_bits(gb, 4);
210
211
    /* get scalefactor index (idsf) for each BFU */
212
107674
    for (i = 0; i < su->num_bfus; i++)
213
105308
        idsfs[i] = get_bits(gb, 6);
214
215
    /* zero idwl/idsf for empty BFUs */
216
20090
    for (i = su->num_bfus; i < AT1_MAX_BFU; i++)
217
17724
        idwls[i] = idsfs[i] = 0;
218
219
    /* read in the spectral data and reconstruct MDCT spectrum of this channel */
220
9464
    for (band_num = 0; band_num < AT1_QMF_BANDS; band_num++) {
221
130130
        for (bfu_num = bfu_bands_t[band_num]; bfu_num < bfu_bands_t[band_num+1]; bfu_num++) {
222
            int pos;
223
224
123032
            int num_specs = specs_per_bfu[bfu_num];
225
123032
            int word_len  = !!idwls[bfu_num] + idwls[bfu_num];
226
123032
            float scale_factor = ff_atrac_sf_table[idsfs[bfu_num]];
227
123032
            bits_used += word_len * num_specs; /* add number of bits consumed by current BFU */
228
229
            /* check for bitstream overflow */
230
123032
            if (bits_used > AT1_SU_MAX_BITS)
231
                return AVERROR_INVALIDDATA;
232
233
            /* get the position of the 1st spec according to the block size mode */
234
123032
            pos = su->log2_block_count[band_num] ? bfu_start_short[bfu_num] : bfu_start_long[bfu_num];
235
236
123032
            if (word_len) {
237
57252
                float   max_quant = 1.0 / (float)((1 << (word_len - 1)) - 1);
238
239
555280
                for (i = 0; i < num_specs; i++) {
240
                    /* read in a quantized spec and convert it to
241
                     * signed int and then inverse quantization
242
                     */
243
498028
                    spec[pos+i] = get_sbits(gb, word_len) * scale_factor * max_quant;
244
                }
245
            } else { /* word_len = 0 -> empty BFU, zero all specs in the empty BFU */
246
65780
                memset(&spec[pos], 0, num_specs * sizeof(float));
247
            }
248
        }
249
    }
250
251
2366
    return 0;
252
}
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2366
static void at1_subband_synthesis(AT1Ctx *q, AT1SUCtx* su, float *pOut)
256
{
257
    float temp[256];
258
    float iqmf_temp[512 + 46];
259
260
    /* combine low and middle bands */
261
2366
    ff_atrac_iqmf(q->bands[0], q->bands[1], 128, temp, su->fst_qmf_delay, iqmf_temp);
262
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    /* delay the signal of the high band by 39 samples */
264
2366
    memcpy( su->last_qmf_delay,    &su->last_qmf_delay[256], sizeof(float) *  39);
265
2366
    memcpy(&su->last_qmf_delay[39], q->bands[2],             sizeof(float) * 256);
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    /* combine (low + middle) and high bands */
268
2366
    ff_atrac_iqmf(temp, su->last_qmf_delay, 256, pOut, su->snd_qmf_delay, iqmf_temp);
269
2366
}
270
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1184
static int atrac1_decode_frame(AVCodecContext *avctx, void *data,
273
                               int *got_frame_ptr, AVPacket *avpkt)
274
{
275
1184
    AVFrame *frame     = data;
276
1184
    const uint8_t *buf = avpkt->data;
277
1184
    int buf_size       = avpkt->size;
278
1184
    AT1Ctx *q          = avctx->priv_data;
279
    int ch, ret;
280
    GetBitContext gb;
281
282
283
1184
    if (buf_size < 212 * avctx->channels) {
284
1
        av_log(avctx, AV_LOG_ERROR, "Not enough data to decode!\n");
285
1
        return AVERROR_INVALIDDATA;
286
    }
287
288
    /* get output buffer */
289
1183
    frame->nb_samples = AT1_SU_SAMPLES;
290
1183
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
291
        return ret;
292
293
3549
    for (ch = 0; ch < avctx->channels; ch++) {
294
2366
        AT1SUCtx* su = &q->SUs[ch];
295
296
2366
        init_get_bits(&gb, &buf[212 * ch], 212 * 8);
297
298
        /* parse block_size_mode, 1st byte */
299
2366
        ret = at1_parse_bsm(&gb, su->log2_block_count);
300
2366
        if (ret < 0)
301
            return ret;
302
303
2366
        ret = at1_unpack_dequant(&gb, su, q->spec);
304
2366
        if (ret < 0)
305
            return ret;
306
307
2366
        ret = at1_imdct_block(su, q);
308
2366
        if (ret < 0)
309
            return ret;
310
2366
        at1_subband_synthesis(q, su, (float *)frame->extended_data[ch]);
311
    }
312
313
1183
    *got_frame_ptr = 1;
314
315
1183
    return avctx->block_align;
316
}
317
318
319
5
static av_cold int atrac1_decode_end(AVCodecContext * avctx)
320
{
321
5
    AT1Ctx *q = avctx->priv_data;
322
323
5
    ff_mdct_end(&q->mdct_ctx[0]);
324
5
    ff_mdct_end(&q->mdct_ctx[1]);
325
5
    ff_mdct_end(&q->mdct_ctx[2]);
326
327
5
    av_freep(&q->fdsp);
328
329
5
    return 0;
330
}
331
332
333
5
static av_cold int atrac1_decode_init(AVCodecContext *avctx)
334
{
335
5
    AT1Ctx *q = avctx->priv_data;
336
    int ret;
337
338
5
    avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
339
340

5
    if (avctx->channels < 1 || avctx->channels > AT1_MAX_CHANNELS) {
341
        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %d\n",
342
               avctx->channels);
343
        return AVERROR(EINVAL);
344
    }
345
346
5
    if (avctx->block_align <= 0) {
347
        av_log(avctx, AV_LOG_ERROR, "Unsupported block align.");
348
        return AVERROR_PATCHWELCOME;
349
    }
350
351
    /* Init the mdct transforms */
352

10
    if ((ret = ff_mdct_init(&q->mdct_ctx[0], 6, 1, -1.0/ (1 << 15))) ||
353
10
        (ret = ff_mdct_init(&q->mdct_ctx[1], 8, 1, -1.0/ (1 << 15))) ||
354
5
        (ret = ff_mdct_init(&q->mdct_ctx[2], 9, 1, -1.0/ (1 << 15)))) {
355
        av_log(avctx, AV_LOG_ERROR, "Error initializing MDCT\n");
356
        atrac1_decode_end(avctx);
357
        return ret;
358
    }
359
360
5
    ff_init_ff_sine_windows(5);
361
362
5
    ff_atrac_generate_tables();
363
364
5
    q->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
365
366
5
    q->bands[0] = q->low;
367
5
    q->bands[1] = q->mid;
368
5
    q->bands[2] = q->high;
369
370
    /* Prepare the mdct overlap buffers */
371
5
    q->SUs[0].spectrum[0] = q->SUs[0].spec1;
372
5
    q->SUs[0].spectrum[1] = q->SUs[0].spec2;
373
5
    q->SUs[1].spectrum[0] = q->SUs[1].spec1;
374
5
    q->SUs[1].spectrum[1] = q->SUs[1].spec2;
375
376
5
    return 0;
377
}
378
379
380
AVCodec ff_atrac1_decoder = {
381
    .name           = "atrac1",
382
    .long_name      = NULL_IF_CONFIG_SMALL("ATRAC1 (Adaptive TRansform Acoustic Coding)"),
383
    .type           = AVMEDIA_TYPE_AUDIO,
384
    .id             = AV_CODEC_ID_ATRAC1,
385
    .priv_data_size = sizeof(AT1Ctx),
386
    .init           = atrac1_decode_init,
387
    .close          = atrac1_decode_end,
388
    .decode         = atrac1_decode_frame,
389
    .capabilities   = AV_CODEC_CAP_DR1,
390
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
391
                                                      AV_SAMPLE_FMT_NONE },
392
};