GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/atrac1.c Lines: 125 140 89.3 %
Date: 2020-09-28 00:47:38 Branches: 54 70 77.1 %

Line Branch Exec Source
1
/*
2
 * ATRAC1 compatible decoder
3
 * Copyright (c) 2009 Maxim Poliakovski
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 * Copyright (c) 2009 Benjamin Larsson
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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
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,
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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
16
 * 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
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
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#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];
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    DECLARE_ALIGNED(32, float, spec1)[AT1_SU_SAMPLES];     ///< mdct buffer
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    DECLARE_ALIGNED(32, float, spec2)[AT1_SU_SAMPLES];     ///< mdct buffer
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    DECLARE_ALIGNED(32, float, fst_qmf_delay)[46];         ///< delay line for the 1st stacked QMF filter
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    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
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} 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
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78
    DECLARE_ALIGNED(32, float,  low)[256];
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    DECLARE_ALIGNED(32, float,  mid)[256];
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    DECLARE_ALIGNED(32, float, high)[512];
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    float*              bands[3];
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    FFTContext          mdct_ctx[3];
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    void (*vector_fmul_window)(float *dst, const float *src0,
84
                               const float *src1, const float *win, int len);
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} AT1Ctx;
86
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/** size of the transform in samples in the long mode for each QMF band */
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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)
94
{
95
7157
    FFTContext* mdct_context = &q->mdct_ctx[nbits - 5 - (nbits > 6)];
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7157
    int transf_size = 1 << nbits;
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98
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)
108
{
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    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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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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123
7098
        if (num_blocks == 1) {
124
            /* 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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128
            /* calc transform size in bits according to the block_size_mode */
129
7085
            nbits = mdct_long_nbits[band_num] - log2_block_count;
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7085
            if (nbits != 5 && nbits != 7 && nbits != 8)
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                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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        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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            q->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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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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7098
        ref_pos += band_samples;
156
    }
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    /* Swap buffers so the mdct overlap works */
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2366
    FFSWAP(float*, su->spectrum[0], su->spectrum[1]);
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161
2366
    return 0;
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}
163
164
/**
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 * Parse the block size mode byte
166
 */
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168
2366
static int at1_parse_bsm(GetBitContext* gb, int log2_block_cnt[AT1_QMF_BANDS])
169
{
170
    int log2_block_count_tmp, i;
171
172
7098
    for (i = 0; i < 2; i++) {
173
        /* low and mid band */
174
4732
        log2_block_count_tmp = get_bits(gb, 2);
175
4732
        if (log2_block_count_tmp & 1)
176
            return AVERROR_INVALIDDATA;
177
4732
        log2_block_cnt[i] = 2 - log2_block_count_tmp;
178
    }
179
180
    /* high band */
181
2366
    log2_block_count_tmp = get_bits(gb, 2);
182

2366
    if (log2_block_count_tmp != 0 && log2_block_count_tmp != 3)
183
        return AVERROR_INVALIDDATA;
184
2366
    log2_block_cnt[IDX_HIGH_BAND] = 3 - log2_block_count_tmp;
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186
2366
    skip_bits(gb, 2);
187
2366
    return 0;
188
}
189
190
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2366
static int at1_unpack_dequant(GetBitContext* gb, AT1SUCtx* su,
192
                              float spec[AT1_SU_SAMPLES])
193
{
194
    int bits_used, band_num, bfu_num, i;
195
    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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198
    /* parse the info byte (2nd byte) telling how much BFUs were coded */
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2366
    su->num_bfus = bfu_amount_tab1[get_bits(gb, 3)];
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201
    /* calc number of consumed bits:
202
        num_BFUs * (idwl(4bits) + idsf(6bits)) + log2_block_count(8bits) + info_byte(8bits)
203
        + info_byte_copy(8bits) + log2_block_count_copy(8bits) */
204
7098
    bits_used = su->num_bfus * 10 + 32 +
205
2366
                bfu_amount_tab2[get_bits(gb, 2)] +
206
2366
                (bfu_amount_tab3[get_bits(gb, 3)] << 1);
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208
    /* get word length index (idwl) for each BFU */
209
107674
    for (i = 0; i < su->num_bfus; i++)
210
105308
        idwls[i] = get_bits(gb, 4);
211
212
    /* get scalefactor index (idsf) for each BFU */
213
107674
    for (i = 0; i < su->num_bfus; i++)
214
105308
        idsfs[i] = get_bits(gb, 6);
215
216
    /* zero idwl/idsf for empty BFUs */
217
20090
    for (i = su->num_bfus; i < AT1_MAX_BFU; i++)
218
17724
        idwls[i] = idsfs[i] = 0;
219
220
    /* read in the spectral data and reconstruct MDCT spectrum of this channel */
221
9464
    for (band_num = 0; band_num < AT1_QMF_BANDS; band_num++) {
222
130130
        for (bfu_num = bfu_bands_t[band_num]; bfu_num < bfu_bands_t[band_num+1]; bfu_num++) {
223
            int pos;
224
225
123032
            int num_specs = specs_per_bfu[bfu_num];
226
123032
            int word_len  = !!idwls[bfu_num] + idwls[bfu_num];
227
123032
            float scale_factor = ff_atrac_sf_table[idsfs[bfu_num]];
228
123032
            bits_used += word_len * num_specs; /* add number of bits consumed by current BFU */
229
230
            /* check for bitstream overflow */
231
123032
            if (bits_used > AT1_SU_MAX_BITS)
232
                return AVERROR_INVALIDDATA;
233
234
            /* get the position of the 1st spec according to the block size mode */
235
123032
            pos = su->log2_block_count[band_num] ? bfu_start_short[bfu_num] : bfu_start_long[bfu_num];
236
237
123032
            if (word_len) {
238
57252
                float   max_quant = 1.0 / (float)((1 << (word_len - 1)) - 1);
239
240
555280
                for (i = 0; i < num_specs; i++) {
241
                    /* read in a quantized spec and convert it to
242
                     * signed int and then inverse quantization
243
                     */
244
498028
                    spec[pos+i] = get_sbits(gb, word_len) * scale_factor * max_quant;
245
                }
246
            } else { /* word_len = 0 -> empty BFU, zero all specs in the empty BFU */
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65780
                memset(&spec[pos], 0, num_specs * sizeof(float));
248
            }
249
        }
250
    }
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252
2366
    return 0;
253
}
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2366
static void at1_subband_synthesis(AT1Ctx *q, AT1SUCtx* su, float *pOut)
257
{
258
    float temp[256];
259
    float iqmf_temp[512 + 46];
260
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    /* combine low and middle bands */
262
2366
    ff_atrac_iqmf(q->bands[0], q->bands[1], 128, temp, su->fst_qmf_delay, iqmf_temp);
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    /* delay the signal of the high band by 39 samples */
265
2366
    memcpy( su->last_qmf_delay,    &su->last_qmf_delay[256], sizeof(float) *  39);
266
2366
    memcpy(&su->last_qmf_delay[39], q->bands[2],             sizeof(float) * 256);
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    /* combine (low + middle) and high bands */
269
2366
    ff_atrac_iqmf(temp, su->last_qmf_delay, 256, pOut, su->snd_qmf_delay, iqmf_temp);
270
2366
}
271
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static int atrac1_decode_frame(AVCodecContext *avctx, void *data,
274
                               int *got_frame_ptr, AVPacket *avpkt)
275
{
276
1184
    AVFrame *frame     = data;
277
1184
    const uint8_t *buf = avpkt->data;
278
1184
    int buf_size       = avpkt->size;
279
1184
    AT1Ctx *q          = avctx->priv_data;
280
    int ch, ret;
281
    GetBitContext gb;
282
283
284
1184
    if (buf_size < 212 * avctx->channels) {
285
1
        av_log(avctx, AV_LOG_ERROR, "Not enough data to decode!\n");
286
1
        return AVERROR_INVALIDDATA;
287
    }
288
289
    /* get output buffer */
290
1183
    frame->nb_samples = AT1_SU_SAMPLES;
291
1183
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
292
        return ret;
293
294
3549
    for (ch = 0; ch < avctx->channels; ch++) {
295
2366
        AT1SUCtx* su = &q->SUs[ch];
296
297
2366
        init_get_bits(&gb, &buf[212 * ch], 212 * 8);
298
299
        /* parse block_size_mode, 1st byte */
300
2366
        ret = at1_parse_bsm(&gb, su->log2_block_count);
301
2366
        if (ret < 0)
302
            return ret;
303
304
2366
        ret = at1_unpack_dequant(&gb, su, q->spec);
305
2366
        if (ret < 0)
306
            return ret;
307
308
2366
        ret = at1_imdct_block(su, q);
309
2366
        if (ret < 0)
310
            return ret;
311
2366
        at1_subband_synthesis(q, su, (float *)frame->extended_data[ch]);
312
    }
313
314
1183
    *got_frame_ptr = 1;
315
316
1183
    return avctx->block_align;
317
}
318
319
320
5
static av_cold int atrac1_decode_end(AVCodecContext * avctx)
321
{
322
5
    AT1Ctx *q = avctx->priv_data;
323
324
5
    ff_mdct_end(&q->mdct_ctx[0]);
325
5
    ff_mdct_end(&q->mdct_ctx[1]);
326
5
    ff_mdct_end(&q->mdct_ctx[2]);
327
328
5
    return 0;
329
}
330
331
332
5
static av_cold int atrac1_decode_init(AVCodecContext *avctx)
333
{
334
5
    AT1Ctx *q = avctx->priv_data;
335
    AVFloatDSPContext *fdsp;
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
        return ret;
357
    }
358
359
5
    ff_init_ff_sine_windows(5);
360
361
5
    ff_atrac_generate_tables();
362
363
5
    fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
364
5
    if (!fdsp)
365
        return AVERROR(ENOMEM);
366
5
    q->vector_fmul_window = fdsp->vector_fmul_window;
367
5
    av_free(fdsp);
368
369
5
    q->bands[0] = q->low;
370
5
    q->bands[1] = q->mid;
371
5
    q->bands[2] = q->high;
372
373
    /* Prepare the mdct overlap buffers */
374
5
    q->SUs[0].spectrum[0] = q->SUs[0].spec1;
375
5
    q->SUs[0].spectrum[1] = q->SUs[0].spec2;
376
5
    q->SUs[1].spectrum[0] = q->SUs[1].spec1;
377
5
    q->SUs[1].spectrum[1] = q->SUs[1].spec2;
378
379
5
    return 0;
380
}
381
382
383
AVCodec ff_atrac1_decoder = {
384
    .name           = "atrac1",
385
    .long_name      = NULL_IF_CONFIG_SMALL("ATRAC1 (Adaptive TRansform Acoustic Coding)"),
386
    .type           = AVMEDIA_TYPE_AUDIO,
387
    .id             = AV_CODEC_ID_ATRAC1,
388
    .priv_data_size = sizeof(AT1Ctx),
389
    .init           = atrac1_decode_init,
390
    .close          = atrac1_decode_end,
391
    .decode         = atrac1_decode_frame,
392
    .capabilities   = AV_CODEC_CAP_DR1,
393
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
394
                                                      AV_SAMPLE_FMT_NONE },
395
    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
396
};