/* * AC-3 parser internal code * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVCODEC_AC3_PARSER_INTERNAL_H#define AVCODEC_AC3_PARSER_INTERNAL_H #include <stddef.h>#include <stdint.h> #include "ac3defs.h"#include "get_bits.h" /** * @struct AC3HeaderInfo * Coded AC-3 header values up to the lfeon element, plus derived values. */typedef struct AC3HeaderInfo {    /** @name Coded elements     * @{     */    uint16_t sync_word;    uint16_t crc1;    uint8_t sr_code;    uint8_t bitstream_id;    uint8_t bitstream_mode;    uint8_t channel_mode;    uint8_t lfe_on;    uint8_t frame_type;    int substreamid;                        ///< substream identification    int center_mix_level;                   ///< Center mix level index    int surround_mix_level;                 ///< Surround mix level index    uint16_t channel_map;    int num_blocks;                         ///< number of audio blocks    int dolby_surround_mode;    /** @} */     /** @name Derived values     * @{     */    uint8_t sr_shift;    uint16_t sample_rate;    uint32_t bit_rate;    uint8_t channels;    uint16_t frame_size;    uint64_t channel_layout;    int8_t ac3_bit_rate_code;    /** @} */} AC3HeaderInfo; /** * Parse AC-3 frame header. * Parse the header up to the lfeon element, which is the first 52 or 54 bits * depending on the audio coding mode. * @param[in]  gbc BitContext containing the first 54 bits of the frame. * @param[out] hdr Pointer to struct where header info is written. * @return Returns 0 on success, -1 if there is a sync word mismatch, * -2 if the bsid (version) element is invalid, -3 if the fscod (sample rate) * element is invalid, or -4 if the frmsizecod (bit rate) element is invalid. */int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr); int avpriv_ac3_parse_header(AC3HeaderInfo **hdr, const uint8_t *buf,                            size_t size); int ff_ac3_find_syncword(const uint8_t *buf, int buf_size); #endif /* AVCODEC_AC3_PARSER_INTERNAL_H */