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/*
* FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
* Copyright (c) 2008 Justin Ruggles
*
* 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
*/
/**
* @file
* FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
*/
#ifndef AVCODEC_FLAC_H
#define AVCODEC_FLAC_H
#include "avcodec.h"
#include "bytestream.h"
#include "get_bits.h"
#define FLAC_STREAMINFO_SIZE 34
#define FLAC_MAX_CHANNELS 8
#define FLAC_MIN_BLOCKSIZE 16
#define FLAC_MAX_BLOCKSIZE 65535
#define FLAC_MIN_FRAME_SIZE 11
enum {
FLAC_CHMODE_INDEPENDENT = 0,
FLAC_CHMODE_LEFT_SIDE = 1,
FLAC_CHMODE_RIGHT_SIDE = 2,
FLAC_CHMODE_MID_SIDE = 3,
};
enum {
FLAC_METADATA_TYPE_STREAMINFO = 0,
FLAC_METADATA_TYPE_PADDING,
FLAC_METADATA_TYPE_APPLICATION,
FLAC_METADATA_TYPE_SEEKTABLE,
FLAC_METADATA_TYPE_VORBIS_COMMENT,
FLAC_METADATA_TYPE_CUESHEET,
FLAC_METADATA_TYPE_PICTURE,
FLAC_METADATA_TYPE_INVALID = 127
};
enum FLACExtradataFormat {
FLAC_EXTRADATA_FORMAT_STREAMINFO = 0,
FLAC_EXTRADATA_FORMAT_FULL_HEADER = 1
};
#define FLACCOMMONINFO \
int samplerate; /**< sample rate */\
int channels; /**< number of channels */\
int bps; /**< bits-per-sample */\
/**
* Data needed from the Streaminfo header for use by the raw FLAC demuxer
* and/or the FLAC decoder.
*/
#define FLACSTREAMINFO \
FLACCOMMONINFO \
int max_blocksize; /**< maximum block size, in samples */\
int max_framesize; /**< maximum frame size, in bytes */\
int64_t samples; /**< total number of samples */\
typedef struct FLACStreaminfo {
FLACSTREAMINFO
} FLACStreaminfo;
typedef struct FLACFrameInfo {
FLACCOMMONINFO
int blocksize; /**< block size of the frame */
int ch_mode; /**< channel decorrelation mode */
int64_t frame_or_sample_num; /**< frame number or sample number */
int is_var_size; /**< specifies if the stream uses variable
block sizes or a fixed block size;
also determines the meaning of
frame_or_sample_num */
} FLACFrameInfo;
/**
* Parse the Streaminfo metadata block
* @param[out] avctx codec context to set basic stream parameters
* @param[out] s where parsed information is stored
* @param[in] buffer pointer to start of 34-byte streaminfo data
*/
void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s,
const uint8_t *buffer);
/**
* Validate the FLAC extradata.
* @param[in] avctx codec context containing the extradata.
* @param[out] format extradata format.
* @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
* @return 1 if valid, 0 if not valid.
*/
int ff_flac_is_extradata_valid(AVCodecContext *avctx,
enum FLACExtradataFormat *format,
uint8_t **streaminfo_start);
/**
* Calculate an estimate for the maximum frame size based on verbatim mode.
* @param blocksize block size, in samples
* @param ch number of channels
* @param bps bits-per-sample
*/
int ff_flac_get_max_frame_size(int blocksize, int ch, int bps);
/**
* Validate and decode a frame header.
* @param avctx AVCodecContext to use as av_log() context
* @param gb GetBitContext from which to read frame header
* @param[out] fi frame information
* @param log_level_offset log level offset. can be used to silence error messages.
* @return non-zero on error, 0 if ok
*/
int ff_flac_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
FLACFrameInfo *fi, int log_level_offset);
void ff_flac_set_channel_layout(AVCodecContext *avctx);
/**
* Parse the metadata block parameters from the header.
* @param[in] block_header header data, at least 4 bytes
* @param[out] last indicator for last metadata block
* @param[out] type metadata block type
* @param[out] size metadata block size
*/
static av_always_inline void flac_parse_block_header(const uint8_t *block_header,
int *last, int *type, int *size)
{
int tmp = bytestream_get_byte(&block_header);
if (last)
*last = tmp & 0x80;
if (type)
*type = tmp & 0x7F;
if (size)
*size = bytestream_get_be24(&block_header);
}
#endif /* AVCODEC_FLAC_H */
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