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/*
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* Xing VBR tagging for LAME.
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*
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* Copyright (c) 1999 A.L. Faber
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*/
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#ifndef LAME_VRBTAG_H
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#define LAME_VRBTAG_H
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#include "lame.h"
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/* -----------------------------------------------------------
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* A Vbr header may be present in the ancillary
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* data field of the first frame of an mp3 bitstream
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* The Vbr header (optionally) contains
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* frames total number of audio frames in the bitstream
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* bytes total number of bytes in the bitstream
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* toc table of contents
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* toc (table of contents) gives seek points
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* for random access
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* the ith entry determines the seek point for
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* i-percent duration
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* seek point in bytes = (toc[i]/256.0) * total_bitstream_bytes
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* e.g. half duration seek point = (toc[50]/256.0) * total_bitstream_bytes
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*/
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#define FRAMES_FLAG 0x0001
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#define BYTES_FLAG 0x0002
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#define TOC_FLAG 0x0004
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#define VBR_SCALE_FLAG 0x0008
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#define NUMTOCENTRIES 100
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#define FRAMES_AND_BYTES (FRAMES_FLAG | BYTES_FLAG)
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/*structure to receive extracted header */
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/* toc may be NULL*/
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typedef struct
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{
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int h_id; /* from MPEG header, 0=MPEG2, 1=MPEG1 */
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int samprate; /* determined from MPEG header */
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int flags; /* from Vbr header data */
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int frames; /* total bit stream frames from Vbr header data */
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int bytes; /* total bit stream bytes from Vbr header data*/
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int vbr_scale; /* encoded vbr scale from Vbr header data*/
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unsigned char toc[NUMTOCENTRIES]; /* may be NULL if toc not desired*/
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int headersize; /* size of VBR header, in bytes */
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} VBRTAGDATA;
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int CheckVbrTag(unsigned char *buf);
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int GetVbrTag(VBRTAGDATA *pTagData, unsigned char *buf);
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int SeekPoint(unsigned char TOC[NUMTOCENTRIES], int file_bytes, float percent);
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int InitVbrTag(lame_global_flags *gfp);
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int PutVbrTag(lame_global_flags *gfp,FILE *fid,int nVbrScale);
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void AddVbrFrame(lame_global_flags *gfp);
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#endif
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