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/*
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 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
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 * Copyright (c) 2008 Justin Ruggles
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 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
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 */
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#ifndef AVCODEC_FLAC_H
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#define AVCODEC_FLAC_H
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#include "avcodec.h"
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#include "get_bits.h"
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#define FLAC_STREAMINFO_SIZE   34
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#define FLAC_MAX_CHANNELS       8
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#define FLAC_MIN_BLOCKSIZE     16
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#define FLAC_MAX_BLOCKSIZE  65535
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#define FLAC_MIN_FRAME_SIZE    11
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enum {
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    FLAC_CHMODE_INDEPENDENT =  0,
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    FLAC_CHMODE_LEFT_SIDE   =  8,
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    FLAC_CHMODE_RIGHT_SIDE  =  9,
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    FLAC_CHMODE_MID_SIDE    = 10,
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};
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enum {
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    FLAC_METADATA_TYPE_STREAMINFO = 0,
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    FLAC_METADATA_TYPE_PADDING,
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    FLAC_METADATA_TYPE_APPLICATION,
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    FLAC_METADATA_TYPE_SEEKTABLE,
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    FLAC_METADATA_TYPE_VORBIS_COMMENT,
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    FLAC_METADATA_TYPE_CUESHEET,
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    FLAC_METADATA_TYPE_PICTURE,
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    FLAC_METADATA_TYPE_INVALID = 127
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};
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enum FLACExtradataFormat {
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    FLAC_EXTRADATA_FORMAT_STREAMINFO  = 0,
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    FLAC_EXTRADATA_FORMAT_FULL_HEADER = 1
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};
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#define FLACCOMMONINFO \
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    int samplerate;         /**< sample rate                             */\
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    int channels;           /**< number of channels                      */\
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    int bps;                /**< bits-per-sample                         */\
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/**
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 * Data needed from the Streaminfo header for use by the raw FLAC demuxer
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 * and/or the FLAC decoder.
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 */
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#define FLACSTREAMINFO \
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    FLACCOMMONINFO \
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    int max_blocksize;      /**< maximum block size, in samples          */\
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    int max_framesize;      /**< maximum frame size, in bytes            */\
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    int64_t samples;        /**< total number of samples                 */\
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typedef struct FLACStreaminfo {
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    FLACSTREAMINFO
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} FLACStreaminfo;
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typedef struct FLACFrameInfo {
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    FLACCOMMONINFO
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    int blocksize;          /**< block size of the frame                 */
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    int ch_mode;            /**< channel decorrelation mode              */
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    int64_t frame_or_sample_num;    /**< frame number or sample number   */
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    int is_var_size;                /**< specifies if the stream uses variable
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                                         block sizes or a fixed block size;
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                                         also determines the meaning of
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                                         frame_or_sample_num             */
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} FLACFrameInfo;
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/**
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 * Parse the Streaminfo metadata block
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 * @param[out] avctx   codec context to set basic stream parameters
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 * @param[out] s       where parsed information is stored
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 * @param[in]  buffer  pointer to start of 34-byte streaminfo data
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 */
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void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s,
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                              const uint8_t *buffer);
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/**
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 * Validate the FLAC extradata.
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 * @param[in]  avctx codec context containing the extradata.
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 * @param[out] format extradata format.
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 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
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 * @return 1 if valid, 0 if not valid.
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 */
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int ff_flac_is_extradata_valid(AVCodecContext *avctx,
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                               enum FLACExtradataFormat *format,
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                               uint8_t **streaminfo_start);
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/**
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 * Parse the metadata block parameters from the header.
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 * @param[in]  block_header header data, at least 4 bytes
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 * @param[out] last indicator for last metadata block
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 * @param[out] type metadata block type
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 * @param[out] size metadata block size
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 */
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void ff_flac_parse_block_header(const uint8_t *block_header,
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                                int *last, int *type, int *size);
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/**
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 * Calculate an estimate for the maximum frame size based on verbatim mode.
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 * @param blocksize block size, in samples
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 * @param ch number of channels
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 * @param bps bits-per-sample
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 */
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int ff_flac_get_max_frame_size(int blocksize, int ch, int bps);
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/**
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 * Validate and decode a frame header.
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 * @param      avctx AVCodecContext to use as av_log() context
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 * @param      gb    GetBitContext from which to read frame header
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 * @param[out] fi    frame information
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 * @param      log_level_offset  log level offset. can be used to silence error messages.
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 * @return non-zero on error, 0 if ok
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 */
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int ff_flac_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
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                                FLACFrameInfo *fi, int log_level_offset);
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#endif /* AVCODEC_FLAC_H */