flac_parse.h (3752B)
1 /* 2 * FLAC (Free Lossless Audio Codec) decoder/parser 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/parser common functions 25 */ 26 27 #ifndef AVCODEC_FLAC_PARSE_H 28 #define AVCODEC_FLAC_PARSE_H 29 30 #include "avcodec.h" 31 #include "get_bits.h" 32 33 typedef struct FLACStreaminfo { 34 int samplerate; /**< sample rate */ 35 int channels; /**< number of channels */ 36 int bps; /**< bits-per-sample */ 37 int max_blocksize; /**< maximum block size, in samples */ 38 int max_framesize; /**< maximum frame size, in bytes */ 39 int64_t samples; /**< total number of samples */ 40 } FLACStreaminfo; 41 42 typedef struct FLACFrameInfo { 43 int samplerate; /**< sample rate */ 44 int channels; /**< number of channels */ 45 int bps; /**< bits-per-sample */ 46 int blocksize; /**< block size of the frame */ 47 int ch_mode; /**< channel decorrelation mode */ 48 int64_t frame_or_sample_num; /**< frame number or sample number */ 49 int is_var_size; /**< specifies if the stream uses variable 50 block sizes or a fixed block size; 51 also determines the meaning of 52 frame_or_sample_num */ 53 } FLACFrameInfo; 54 55 /** 56 * Parse the Streaminfo metadata block 57 * @param[out] avctx codec context to set basic stream parameters 58 * @param[out] s where parsed information is stored 59 * @param[in] buffer pointer to start of 34-byte streaminfo data 60 * 61 * @return negative error code on faiure or >= 0 on success 62 */ 63 int ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s, 64 const uint8_t *buffer); 65 66 /** 67 * Validate the FLAC extradata. 68 * @param[in] avctx codec context containing the extradata. 69 * @param[out] format extradata format. 70 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data. 71 * @return 1 if valid, 0 if not valid. 72 */ 73 int ff_flac_is_extradata_valid(AVCodecContext *avctx, 74 uint8_t **streaminfo_start); 75 76 /** 77 * Validate and decode a frame header. 78 * @param logctx context for logging 79 * @param gb GetBitContext from which to read frame header 80 * @param[out] fi frame information 81 * @param log_level_offset log level offset. can be used to silence error messages. 82 * @return non-zero on error, 0 if ok 83 */ 84 int ff_flac_decode_frame_header(void *logctx, GetBitContext *gb, 85 FLACFrameInfo *fi, int log_level_offset); 86 87 void ff_flac_set_channel_layout(AVCodecContext *avctx, int channels); 88 89 #endif /* AVCODEC_FLAC_PARSE_H */