ffmpeg/libavcodec/vorbis_parser_internal.h

   1 /*
   2  * Copyright (c) 2012 Justin Ruggles
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file
  23  * Vorbis audio parser
  24  *
  25  * Determines the duration for each packet.
  26  */
  27
  28 #ifndef AVCODEC_VORBIS_PARSER_H
  29 #define AVCODEC_VORBIS_PARSER_H
  30
  31 #include "avcodec.h"
  32 #include "vorbis_parser.h"
  33
  34 struct AVVorbisParseContext {
  35     const AVClass *class;
  36     int extradata_parsed;       ///< we have attempted to parse extradata
  37     int valid_extradata;        ///< extradata is valid, so we can calculate duration
  38     int blocksize[2];           ///< short and long window sizes
  39     int previous_blocksize;     ///< previous window size
  40     int mode_blocksize[64];     ///< window size mapping for each mode
  41     int mode_count;             ///< number of modes
  42     int mode_mask;              ///< bitmask used to get the mode in each packet
  43     int prev_mask;              ///< bitmask used to get the previous mode flag in each packet
  44 };
  45
  46 #if LIBAVCODEC_VERSION_MAJOR < 57
  47 /**
  48  * Initialize the Vorbis parser using headers in the extradata.
  49  *
  50  * @param avctx codec context
  51  * @param s     Vorbis parser context
  52  */
  53 int avpriv_vorbis_parse_extradata(AVCodecContext *avctx, AVVorbisParseContext *s);
  54
  55 /**
  56  * Get the duration for a Vorbis packet.
  57  *
  58  * avpriv_vorbis_parse_extradata() must have been successfully called prior to
  59  * this in order for a correct duration to be returned. If @p flags is @c NULL,
  60  * special frames are considered invalid.
  61  *
  62  * @param s        Vorbis parser context
  63  * @param buf      buffer containing a Vorbis frame
  64  * @param buf_size size of the buffer
  65  * @param flags    flags for special frames
  66  */
  67 int avpriv_vorbis_parse_frame_flags(AVVorbisParseContext *s, const uint8_t *buf,
  68                                     int buf_size, int *flags);
  69
  70 /**
  71  * Get the duration for a Vorbis packet.
  72  *
  73  * avpriv_vorbis_parse_extradata() must have been successfully called prior to
  74  * this in order for a correct duration to be returned.
  75  *
  76  * @param s        Vorbis parser context
  77  * @param buf      buffer containing a Vorbis frame
  78  * @param buf_size size of the buffer
  79  */
  80 int avpriv_vorbis_parse_frame(AVVorbisParseContext *s, const uint8_t *buf,
  81                               int buf_size);
  82
  83 void avpriv_vorbis_parse_reset(AVVorbisParseContext *s);
  84 #endif
  85
  86 #endif /* AVCODEC_VORBIS_PARSER_H */