1/*
2 * TAK common code
3 * Copyright (c) 2012 Paul B Mahol
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "libavutil/crc.h"
23#include "libavutil/intreadwrite.h"
24#include "tak.h"
25
26static const int64_t tak_channel_layouts[] = {
27    0,
28    AV_CH_FRONT_LEFT,
29    AV_CH_FRONT_RIGHT,
30    AV_CH_FRONT_CENTER,
31    AV_CH_LOW_FREQUENCY,
32    AV_CH_BACK_LEFT,
33    AV_CH_BACK_RIGHT,
34    AV_CH_FRONT_LEFT_OF_CENTER,
35    AV_CH_FRONT_RIGHT_OF_CENTER,
36    AV_CH_BACK_CENTER,
37    AV_CH_SIDE_LEFT,
38    AV_CH_SIDE_RIGHT,
39    AV_CH_TOP_CENTER,
40    AV_CH_TOP_FRONT_LEFT,
41    AV_CH_TOP_FRONT_CENTER,
42    AV_CH_TOP_FRONT_RIGHT,
43    AV_CH_TOP_BACK_LEFT,
44    AV_CH_TOP_BACK_CENTER,
45    AV_CH_TOP_BACK_RIGHT,
46};
47
48static const uint16_t frame_duration_type_quants[] = {
49    3, 4, 6, 8, 4096, 8192, 16384, 512, 1024, 2048,
50};
51
52static int tak_get_nb_samples(int sample_rate, enum TAKFrameSizeType type)
53{
54    int nb_samples, max_nb_samples;
55
56    if (type <= TAK_FST_250ms) {
57        nb_samples     = sample_rate * frame_duration_type_quants[type] >>
58                         TAK_FRAME_DURATION_QUANT_SHIFT;
59        max_nb_samples = 16384;
60    } else if (type < FF_ARRAY_ELEMS(frame_duration_type_quants)) {
61        nb_samples     = frame_duration_type_quants[type];
62        max_nb_samples = sample_rate *
63                         frame_duration_type_quants[TAK_FST_250ms] >>
64                         TAK_FRAME_DURATION_QUANT_SHIFT;
65    } else {
66        return AVERROR_INVALIDDATA;
67    }
68
69    if (nb_samples <= 0 || nb_samples > max_nb_samples)
70        return AVERROR_INVALIDDATA;
71
72    return nb_samples;
73}
74
75int ff_tak_check_crc(const uint8_t *buf, unsigned int buf_size)
76{
77    uint32_t crc, CRC;
78
79    if (buf_size < 4)
80        return AVERROR_INVALIDDATA;
81    buf_size -= 3;
82
83    CRC = AV_RB24(buf + buf_size);
84    crc = av_crc(av_crc_get_table(AV_CRC_24_IEEE), 0xCE04B7U, buf, buf_size);
85    if (CRC != crc)
86        return AVERROR_INVALIDDATA;
87
88    return 0;
89}
90
91void avpriv_tak_parse_streaminfo(GetBitContext *gb, TAKStreamInfo *s)
92{
93    uint64_t channel_mask = 0;
94    int frame_type, i;
95
96    s->codec = get_bits(gb, TAK_ENCODER_CODEC_BITS);
97    skip_bits(gb, TAK_ENCODER_PROFILE_BITS);
98
99    frame_type = get_bits(gb, TAK_SIZE_FRAME_DURATION_BITS);
100    s->samples = get_bits64(gb, TAK_SIZE_SAMPLES_NUM_BITS);
101
102    s->data_type   = get_bits(gb, TAK_FORMAT_DATA_TYPE_BITS);
103    s->sample_rate = get_bits(gb, TAK_FORMAT_SAMPLE_RATE_BITS) +
104                     TAK_SAMPLE_RATE_MIN;
105    s->bps         = get_bits(gb, TAK_FORMAT_BPS_BITS) +
106                     TAK_BPS_MIN;
107    s->channels    = get_bits(gb, TAK_FORMAT_CHANNEL_BITS) +
108                     TAK_CHANNELS_MIN;
109
110    if (get_bits1(gb)) {
111        skip_bits(gb, TAK_FORMAT_VALID_BITS);
112        if (get_bits1(gb)) {
113            for (i = 0; i < s->channels; i++) {
114                int value = get_bits(gb, TAK_FORMAT_CH_LAYOUT_BITS);
115
116                if (value < FF_ARRAY_ELEMS(tak_channel_layouts))
117                    channel_mask |= tak_channel_layouts[value];
118            }
119        }
120    }
121
122    s->ch_layout     = channel_mask;
123    s->frame_samples = tak_get_nb_samples(s->sample_rate, frame_type);
124}
125
126int ff_tak_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
127                               TAKStreamInfo *ti, int log_level_offset)
128{
129    if (get_bits(gb, TAK_FRAME_HEADER_SYNC_ID_BITS) != TAK_FRAME_HEADER_SYNC_ID) {
130        av_log(avctx, AV_LOG_ERROR + log_level_offset, "missing sync id\n");
131        return AVERROR_INVALIDDATA;
132    }
133
134    ti->flags     = get_bits(gb, TAK_FRAME_HEADER_FLAGS_BITS);
135    ti->frame_num = get_bits(gb, TAK_FRAME_HEADER_NO_BITS);
136
137    if (ti->flags & TAK_FRAME_FLAG_IS_LAST) {
138        ti->last_frame_samples = get_bits(gb, TAK_FRAME_HEADER_SAMPLE_COUNT_BITS) + 1;
139        skip_bits(gb, 2);
140    } else {
141        ti->last_frame_samples = 0;
142    }
143
144    if (ti->flags & TAK_FRAME_FLAG_HAS_INFO) {
145        avpriv_tak_parse_streaminfo(gb, ti);
146
147        if (get_bits(gb, 6))
148            skip_bits(gb, 25);
149        align_get_bits(gb);
150    }
151
152    if (ti->flags & TAK_FRAME_FLAG_HAS_METADATA)
153        return AVERROR_INVALIDDATA;
154
155    skip_bits(gb, 24);
156
157    return 0;
158}
159