yading@10: /*
yading@10:  * TAK common code
yading@10:  * Copyright (c) 2012 Paul B Mahol
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "libavutil/bswap.h"
yading@10: #include "libavutil/crc.h"
yading@10: #include "libavutil/intreadwrite.h"
yading@10: #include "tak.h"
yading@10: 
yading@10: static const int64_t tak_channel_layouts[] = {
yading@10:     0,
yading@10:     AV_CH_FRONT_LEFT,
yading@10:     AV_CH_FRONT_RIGHT,
yading@10:     AV_CH_FRONT_CENTER,
yading@10:     AV_CH_LOW_FREQUENCY,
yading@10:     AV_CH_BACK_LEFT,
yading@10:     AV_CH_BACK_RIGHT,
yading@10:     AV_CH_FRONT_LEFT_OF_CENTER,
yading@10:     AV_CH_FRONT_RIGHT_OF_CENTER,
yading@10:     AV_CH_BACK_CENTER,
yading@10:     AV_CH_SIDE_LEFT,
yading@10:     AV_CH_SIDE_RIGHT,
yading@10:     AV_CH_TOP_CENTER,
yading@10:     AV_CH_TOP_FRONT_LEFT,
yading@10:     AV_CH_TOP_FRONT_CENTER,
yading@10:     AV_CH_TOP_FRONT_RIGHT,
yading@10:     AV_CH_TOP_BACK_LEFT,
yading@10:     AV_CH_TOP_BACK_CENTER,
yading@10:     AV_CH_TOP_BACK_RIGHT,
yading@10: };
yading@10: 
yading@10: static const uint16_t frame_duration_type_quants[] = {
yading@10:     3, 4, 6, 8, 4096, 8192, 16384, 512, 1024, 2048,
yading@10: };
yading@10: 
yading@10: static int tak_get_nb_samples(int sample_rate, enum TAKFrameSizeType type)
yading@10: {
yading@10:     int nb_samples, max_nb_samples;
yading@10: 
yading@10:     if (type <= TAK_FST_250ms) {
yading@10:         nb_samples     = sample_rate * frame_duration_type_quants[type] >>
yading@10:                          TAK_FRAME_DURATION_QUANT_SHIFT;
yading@10:         max_nb_samples = 16384;
yading@10:     } else if (type < FF_ARRAY_ELEMS(frame_duration_type_quants)) {
yading@10:         nb_samples     = frame_duration_type_quants[type];
yading@10:         max_nb_samples = sample_rate *
yading@10:                          frame_duration_type_quants[TAK_FST_250ms] >>
yading@10:                          TAK_FRAME_DURATION_QUANT_SHIFT;
yading@10:     } else {
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     if (nb_samples <= 0 || nb_samples > max_nb_samples)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     return nb_samples;
yading@10: }
yading@10: 
yading@10: static int crc_init = 0;
yading@10: #if CONFIG_SMALL
yading@10: #define CRC_TABLE_SIZE 257
yading@10: #else
yading@10: #define CRC_TABLE_SIZE 1024
yading@10: #endif
yading@10: static AVCRC crc_24[CRC_TABLE_SIZE];
yading@10: 
yading@10: av_cold void ff_tak_init_crc(void)
yading@10: {
yading@10:     if (!crc_init) {
yading@10:         av_crc_init(crc_24, 0, 24, 0x864CFBU, sizeof(crc_24));
yading@10:         crc_init = 1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: int ff_tak_check_crc(const uint8_t *buf, unsigned int buf_size)
yading@10: {
yading@10:     uint32_t crc, CRC;
yading@10: 
yading@10:     if (buf_size < 4)
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     buf_size -= 3;
yading@10: 
yading@10:     CRC = av_bswap32(AV_RL24(buf + buf_size)) >> 8;
yading@10:     crc = av_crc(crc_24, 0xCE04B7U, buf, buf_size);
yading@10:     if (CRC != crc)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: void avpriv_tak_parse_streaminfo(GetBitContext *gb, TAKStreamInfo *s)
yading@10: {
yading@10:     uint64_t channel_mask = 0;
yading@10:     int frame_type, i;
yading@10: 
yading@10:     s->codec = get_bits(gb, TAK_ENCODER_CODEC_BITS);
yading@10:     skip_bits(gb, TAK_ENCODER_PROFILE_BITS);
yading@10: 
yading@10:     frame_type = get_bits(gb, TAK_SIZE_FRAME_DURATION_BITS);
yading@10:     s->samples = get_bits64(gb, TAK_SIZE_SAMPLES_NUM_BITS);
yading@10: 
yading@10:     s->data_type   = get_bits(gb, TAK_FORMAT_DATA_TYPE_BITS);
yading@10:     s->sample_rate = get_bits(gb, TAK_FORMAT_SAMPLE_RATE_BITS) +
yading@10:                      TAK_SAMPLE_RATE_MIN;
yading@10:     s->bps         = get_bits(gb, TAK_FORMAT_BPS_BITS) +
yading@10:                      TAK_BPS_MIN;
yading@10:     s->channels    = get_bits(gb, TAK_FORMAT_CHANNEL_BITS) +
yading@10:                      TAK_CHANNELS_MIN;
yading@10: 
yading@10:     if (get_bits1(gb)) {
yading@10:         skip_bits(gb, TAK_FORMAT_VALID_BITS);
yading@10:         if (get_bits1(gb)) {
yading@10:             for (i = 0; i < s->channels; i++) {
yading@10:                 int value = get_bits(gb, TAK_FORMAT_CH_LAYOUT_BITS);
yading@10: 
yading@10:                 if (value < FF_ARRAY_ELEMS(tak_channel_layouts))
yading@10:                     channel_mask |= tak_channel_layouts[value];
yading@10:             }
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     s->ch_layout     = channel_mask;
yading@10:     s->frame_samples = tak_get_nb_samples(s->sample_rate, frame_type);
yading@10: }
yading@10: 
yading@10: int ff_tak_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
yading@10:                                TAKStreamInfo *ti, int log_level_offset)
yading@10: {
yading@10:     if (get_bits(gb, TAK_FRAME_HEADER_SYNC_ID_BITS) != TAK_FRAME_HEADER_SYNC_ID) {
yading@10:         av_log(avctx, AV_LOG_ERROR + log_level_offset, "missing sync id\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     ti->flags     = get_bits(gb, TAK_FRAME_HEADER_FLAGS_BITS);
yading@10:     ti->frame_num = get_bits(gb, TAK_FRAME_HEADER_NO_BITS);
yading@10: 
yading@10:     if (ti->flags & TAK_FRAME_FLAG_IS_LAST) {
yading@10:         ti->last_frame_samples = get_bits(gb, TAK_FRAME_HEADER_SAMPLE_COUNT_BITS) + 1;
yading@10:         skip_bits(gb, 2);
yading@10:     } else {
yading@10:         ti->last_frame_samples = 0;
yading@10:     }
yading@10: 
yading@10:     if (ti->flags & TAK_FRAME_FLAG_HAS_INFO) {
yading@10:         avpriv_tak_parse_streaminfo(gb, ti);
yading@10: 
yading@10:         if (get_bits(gb, 6))
yading@10:             skip_bits(gb, 25);
yading@10:         align_get_bits(gb);
yading@10:     }
yading@10: 
yading@10:     if (ti->flags & TAK_FRAME_FLAG_HAS_METADATA)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     skip_bits(gb, 24);
yading@10: 
yading@10:     return 0;
yading@10: }