From 5602a464c9f9e3c0922f5cfeccaf2fa1c40b2401 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 15 Jan 2012 13:38:03 -0500 Subject: avcodec: add a Vorbis parser to get packet duration This also allows for removing some of the Vorbis-related hacks. --- libavcodec/vorbis_parser.h | 68 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 libavcodec/vorbis_parser.h (limited to 'libavcodec/vorbis_parser.h') diff --git a/libavcodec/vorbis_parser.h b/libavcodec/vorbis_parser.h new file mode 100644 index 0000000000..480a918f7b --- /dev/null +++ b/libavcodec/vorbis_parser.h @@ -0,0 +1,68 @@ +/* + * Copyright (c) 2012 Justin Ruggles + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * Vorbis audio parser + * + * Determines the duration for each packet. + */ + +#ifndef AVCODEC_VORBIS_PARSER_H +#define AVCODEC_VORBIS_PARSER_H + +#include "avcodec.h" + +typedef struct VorbisParseContext { + AVCodecContext *avctx; ///< codec context + int extradata_parsed; ///< we have attempted to parse extradata + int valid_extradata; ///< extradata is valid, so we can calculate duration + int blocksize[2]; ///< short and long window sizes + int previous_blocksize; ///< previous window size + int mode_blocksize[64]; ///< window size mapping for each mode + int mode_count; ///< number of modes + int mode_mask; ///< bitmask used to get the mode in each packet + int prev_mask; ///< bitmask used to get the previous mode flag in each packet +} VorbisParseContext; + +/** + * Initialize the Vorbis parser using headers in the extradata. + * + * @param avctx codec context + * @param s Vorbis parser context + */ +int avpriv_vorbis_parse_extradata(AVCodecContext *avctx, VorbisParseContext *s); + +/** + * Get the duration for a Vorbis packet. + * + * avpriv_vorbis_parse_extradata() must have been successfully called prior to + * this in order for a correct duration to be returned. + * + * @param s Vorbis parser context + * @param buf buffer containing a Vorbis frame + * @param buf_size size of the buffer + */ +int avpriv_vorbis_parse_frame(VorbisParseContext *s, const uint8_t *buf, + int buf_size); + +void avpriv_vorbis_parse_reset(VorbisParseContext *s); + +#endif /* AVCODEC_VORBIS_PARSER_H */ -- cgit v1.2.3