1/* 2 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions 3 * Copyright (c) 2008 Justin Ruggles 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions 25 */ 26 27#ifndef AVCODEC_FLAC_H 28#define AVCODEC_FLAC_H 29 30#include "avcodec.h" 31 32#define FLAC_STREAMINFO_SIZE 34 33#define FLAC_MAX_CHANNELS 8 34#define FLAC_MIN_BLOCKSIZE 16 35#define FLAC_MAX_BLOCKSIZE 65535 36 37enum { 38 FLAC_CHMODE_INDEPENDENT = 0, 39 FLAC_CHMODE_LEFT_SIDE = 8, 40 FLAC_CHMODE_RIGHT_SIDE = 9, 41 FLAC_CHMODE_MID_SIDE = 10, 42}; 43 44enum { 45 FLAC_METADATA_TYPE_STREAMINFO = 0, 46 FLAC_METADATA_TYPE_PADDING, 47 FLAC_METADATA_TYPE_APPLICATION, 48 FLAC_METADATA_TYPE_SEEKTABLE, 49 FLAC_METADATA_TYPE_VORBIS_COMMENT, 50 FLAC_METADATA_TYPE_CUESHEET, 51 FLAC_METADATA_TYPE_PICTURE, 52 FLAC_METADATA_TYPE_INVALID = 127 53}; 54 55enum FLACExtradataFormat { 56 FLAC_EXTRADATA_FORMAT_STREAMINFO = 0, 57 FLAC_EXTRADATA_FORMAT_FULL_HEADER = 1 58}; 59 60#define FLACCOMMONINFO \ 61 int samplerate; /**< sample rate */\ 62 int channels; /**< number of channels */\ 63 int bps; /**< bits-per-sample */\ 64 65/** 66 * Data needed from the Streaminfo header for use by the raw FLAC demuxer 67 * and/or the FLAC decoder. 68 */ 69#define FLACSTREAMINFO \ 70 FLACCOMMONINFO \ 71 int max_blocksize; /**< maximum block size, in samples */\ 72 int max_framesize; /**< maximum frame size, in bytes */\ 73 int64_t samples; /**< total number of samples */\ 74 75typedef struct FLACStreaminfo { 76 FLACSTREAMINFO 77} FLACStreaminfo; 78 79typedef struct FLACFrameInfo { 80 FLACCOMMONINFO 81 int blocksize; /**< block size of the frame */ 82 int ch_mode; /**< channel decorrelation mode */ 83} FLACFrameInfo; 84 85/** 86 * Parse the Streaminfo metadata block 87 * @param[out] avctx codec context to set basic stream parameters 88 * @param[out] s where parsed information is stored 89 * @param[in] buffer pointer to start of 34-byte streaminfo data 90 */ 91void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s, 92 const uint8_t *buffer); 93 94/** 95 * Validate the FLAC extradata. 96 * @param[in] avctx codec context containing the extradata. 97 * @param[out] format extradata format. 98 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data. 99 * @return 1 if valid, 0 if not valid. 100 */ 101int ff_flac_is_extradata_valid(AVCodecContext *avctx, 102 enum FLACExtradataFormat *format, 103 uint8_t **streaminfo_start); 104 105/** 106 * Parse the metadata block parameters from the header. 107 * @param[in] block_header header data, at least 4 bytes 108 * @param[out] last indicator for last metadata block 109 * @param[out] type metadata block type 110 * @param[out] size metadata block size 111 */ 112void ff_flac_parse_block_header(const uint8_t *block_header, 113 int *last, int *type, int *size); 114 115/** 116 * Calculate an estimate for the maximum frame size based on verbatim mode. 117 * @param blocksize block size, in samples 118 * @param ch number of channels 119 * @param bps bits-per-sample 120 */ 121int ff_flac_get_max_frame_size(int blocksize, int ch, int bps); 122 123#endif /* AVCODEC_FLAC_H */ 124