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/*
* AC3 parser prototypes
* Copyright (c) 2003 Fabrice Bellard.
* Copyright (c) 2003 Michael Niedermayer.
*
* 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 FFMPEG_AC3_PARSER_H
#define FFMPEG_AC3_PARSER_H
#include "ac3.h"
#include "bitstream.h"
typedef enum {
AC3_PARSE_ERROR_SYNC = -1,
AC3_PARSE_ERROR_BSID = -2,
AC3_PARSE_ERROR_SAMPLE_RATE = -3,
AC3_PARSE_ERROR_FRAME_SIZE = -4,
AC3_PARSE_ERROR_FRAME_TYPE = -5,
AC3_PARSE_ERROR_CRC = -6,
} AC3ParseError;
/**
* Parses AC-3 frame header.
* Parses the header up to the lfeon element, which is the first 52 or 54 bits
* depending on the audio coding mode.
* @param gbc[in] BitContext containing the first 54 bits of the frame.
* @param hdr[out] 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);
/**
* Parses AC-3 frame header and sets channel_map
* Parses the header up to the lfeon (channel_map in E-AC-3)
* element, which is the first 52, 54 or 104 bits depending
* on the audio coding mode.
* @param gbc[in] BitContext containing the first 54 bits of the frame.
* @param hdr[out] Pointer to struct where header info is written.
* @return value returned by ff_ac3_parse_header
*/
int ff_ac3_parse_header_full(GetBitContext *gbc, AC3HeaderInfo *hdr);
#endif /* FFMPEG_AC3_PARSER_H */
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