From 5089884e3c9d7369c7a6bae6da7f28de41365ec7 Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Sun, 28 Aug 2022 17:12:30 +0200 Subject: avcodec/flac: Move decoder+parser stuff into a new header, flac_parse.h (The FLAC parser currently ignores the streaminfo block; therefore some of this is decoder-only. Given that the FLAC parser should probably use the streaminfo block, this stuff is moved to flac_parse.h.) Signed-off-by: Andreas Rheinhardt --- libavcodec/flac_parse.h | 89 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 libavcodec/flac_parse.h (limited to 'libavcodec/flac_parse.h') diff --git a/libavcodec/flac_parse.h b/libavcodec/flac_parse.h new file mode 100644 index 0000000000..67a7320bea --- /dev/null +++ b/libavcodec/flac_parse.h @@ -0,0 +1,89 @@ +/* + * FLAC (Free Lossless Audio Codec) decoder/parser 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/parser common functions + */ + +#ifndef AVCODEC_FLAC_PARSE_H +#define AVCODEC_FLAC_PARSE_H + +#include "avcodec.h" +#include "get_bits.h" + +typedef struct FLACStreaminfo { + int samplerate; /**< sample rate */ + int channels; /**< number of channels */ + int bps; /**< bits-per-sample */ + int max_blocksize; /**< maximum block size, in samples */ + int max_framesize; /**< maximum frame size, in bytes */ + int64_t samples; /**< total number of samples */ +} FLACStreaminfo; + +typedef struct FLACFrameInfo { + int samplerate; /**< sample rate */ + int channels; /**< number of channels */ + int bps; /**< bits-per-sample */ + 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 + * + * @return negative error code on faiure or >= 0 on success + */ +int 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, + uint8_t **streaminfo_start); + +/** + * 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, int channels); + +#endif /* AVCODEC_FLAC_PARSE_H */ -- cgit v1.2.3