| 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 | |
| 26 | static 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 | |
| 48 | static const uint16_t frame_duration_type_quants[] = { |
| 49 | 3, 4, 6, 8, 4096, 8192, 16384, 512, 1024, 2048, |
| 50 | }; |
| 51 | |
| 52 | static 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 | |
| 75 | int 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 | |
| 91 | void 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 | |
| 126 | int 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 | } |