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/****************************************************************************** |
/***************************************************************************** |
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* * |
* |
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* This file is part of XviD, a free MPEG-4 video encoder/decoder * |
* XVID MPEG-4 VIDEO CODEC |
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* * |
* - Bitstream reader/writer inlined functions and constants- |
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* XviD is an implementation of a part of one or more MPEG-4 Video tools * |
* |
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* as specified in ISO/IEC 14496-2 standard. Those intending to use this * |
* Copyright (C) 2001-2003 Peter Ross <pross@xvid.org> |
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* software module in hardware or software products are advised that its * |
* |
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* use may infringe existing patents or copyrights, and any such use * |
* This program is free software ; you can redistribute it and/or modify |
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* would be at such party's own risk. The original developer of this * |
* it under the terms of the GNU General Public License as published by |
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* software module and his/her company, and subsequent editors and their * |
* the Free Software Foundation ; either version 2 of the License, or |
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* companies, will have no liability for use of this software or * |
* (at your option) any later version. |
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* modifications or derivatives thereof. * |
* |
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* * |
* This program is distributed in the hope that it will be useful, |
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* XviD is free software; you can redistribute it and/or modify it * |
* but WITHOUT ANY WARRANTY ; without even the implied warranty of |
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* under the terms of the GNU General Public License as published by * |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* the Free Software Foundation; either version 2 of the License, or * |
* GNU General Public License for more details. |
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* (at your option) any later version. * |
* |
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* * |
* You should have received a copy of the GNU General Public License |
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* XviD is distributed in the hope that it will be useful, but * |
* along with this program ; if not, write to the Free Software |
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* WITHOUT ANY WARRANTY; without even the implied warranty of * |
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
* |
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* GNU General Public License for more details. * |
* $Id$ |
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* * |
* |
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* You should have received a copy of the GNU General Public License * |
****************************************************************************/ |
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* along with this program; if not, write to the Free Software * |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * |
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* * |
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******************************************************************************/ |
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/****************************************************************************** |
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* * |
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* bitstream.h * |
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* * |
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* Copyright (C) 2001 - Peter Ross <pross@cs.rmit.edu.au> * |
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* * |
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* For more information visit the XviD homepage: http://www.xvid.org * |
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* * |
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******************************************************************************/ |
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/****************************************************************************** |
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* * |
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* Revision history: * |
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* * |
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* 26.03.2002 interlacing support - modified putvol/vopheaders paramters |
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* 04.03.2002 putbits speedup (Isibaar) * |
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* 03.03.2002 merged BITREADER and BITWRITER (Isibaar) * |
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* 16.12.2001 inital version * |
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* * |
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******************************************************************************/ |
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#ifndef _BITSTREAM_H_ |
#ifndef _BITSTREAM_H_ |
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#define _BITSTREAM_H_ |
#define _BITSTREAM_H_ |
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#include "../decoder.h" |
#include "../decoder.h" |
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#include "../encoder.h" |
#include "../encoder.h" |
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// comment any #defs we dont use |
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/***************************************************************************** |
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* Constants |
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****************************************************************************/ |
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/* comment any #defs we dont use */ |
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#define VIDOBJ_START_CODE 0x00000100 /* ..0x0000011f */ |
#define VIDOBJ_START_CODE 0x00000100 /* ..0x0000011f */ |
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#define VIDOBJLAY_START_CODE 0x00000120 /* ..0x0000012f */ |
#define VIDOBJLAY_START_CODE 0x00000120 /* ..0x0000012f */ |
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#define VISOBJSEQ_STOP_CODE 0x000001b1 /* ??? */ |
#define VISOBJSEQ_STOP_CODE 0x000001b1 /* ??? */ |
44 |
#define USERDATA_START_CODE 0x000001b2 |
#define USERDATA_START_CODE 0x000001b2 |
45 |
#define GRPOFVOP_START_CODE 0x000001b3 |
#define GRPOFVOP_START_CODE 0x000001b3 |
46 |
//#define VIDSESERR_ERROR_CODE 0x000001b4 |
/*#define VIDSESERR_ERROR_CODE 0x000001b4 */ |
47 |
#define VISOBJ_START_CODE 0x000001b5 |
#define VISOBJ_START_CODE 0x000001b5 |
48 |
//#define SLICE_START_CODE 0x000001b7 |
#define VOP_START_CODE 0x000001b6 |
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//#define EXT_START_CODE 0x000001b8 |
/*#define STUFFING_START_CODE 0x000001c3 */ |
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51 |
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#define VISOBJ_TYPE_VIDEO 1 |
#define VISOBJ_TYPE_VIDEO 1 |
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//#define VISOBJ_TYPE_STILLTEXTURE 2 |
/*#define VISOBJ_TYPE_STILLTEXTURE 2 */ |
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//#define VISOBJ_TYPE_MESH 3 |
/*#define VISOBJ_TYPE_MESH 3 */ |
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//#define VISOBJ_TYPE_FBA 4 |
/*#define VISOBJ_TYPE_FBA 4 */ |
56 |
//#define VISOBJ_TYPE_3DMESH 5 |
/*#define VISOBJ_TYPE_3DMESH 5 */ |
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58 |
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#define VIDOBJLAY_TYPE_SIMPLE 1 |
#define VIDOBJLAY_TYPE_SIMPLE 1 |
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//#define VIDOBJLAY_TYPE_SIMPLE_SCALABLE 2 |
/*#define VIDOBJLAY_TYPE_SIMPLE_SCALABLE 2 */ |
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#define VIDOBJLAY_TYPE_CORE 3 |
/*#define VIDOBJLAY_TYPE_CORE 3 */ |
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#define VIDOBJLAY_TYPE_MAIN 4 |
/*#define VIDOBJLAY_TYPE_MAIN 4 */ |
63 |
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/*#define VIDOBJLAY_TYPE_NBIT 5 */ |
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/*#define VIDOBJLAY_TYPE_ANIM_TEXT 6 */ |
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//#define VIDOBJLAY_AR_SQUARE 1 |
/*#define VIDOBJLAY_TYPE_ANIM_MESH 7 */ |
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//#define VIDOBJLAY_AR_625TYPE_43 2 |
/*#define VIDOBJLAY_TYPE_SIMPLE_FACE 8 */ |
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//#define VIDOBJLAY_AR_525TYPE_43 3 |
/*#define VIDOBJLAY_TYPE_STILL_SCALABLE 9 */ |
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//#define VIDOBJLAY_AR_625TYPE_169 8 |
#define VIDOBJLAY_TYPE_ART_SIMPLE 10 |
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//#define VIDOBJLAY_AR_525TYPE_169 9 |
/*#define VIDOBJLAY_TYPE_CORE_SCALABLE 11 */ |
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/*#define VIDOBJLAY_TYPE_ACE 12 */ |
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/*#define VIDOBJLAY_TYPE_ADVANCED_SCALABLE_TEXTURE 13 */ |
72 |
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/*#define VIDOBJLAY_TYPE_SIMPLE_FBA 14 */ |
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/*#define VIDEOJLAY_TYPE_SIMPLE_STUDIO 15*/ |
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/*#define VIDEOJLAY_TYPE_CORE_STUDIO 16*/ |
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#define VIDOBJLAY_TYPE_ASP 17 |
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/*#define VIDOBJLAY_TYPE_FGS 18*/ |
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/*#define VIDOBJLAY_AR_SQUARE 1 */ |
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/*#define VIDOBJLAY_AR_625TYPE_43 2 */ |
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/*#define VIDOBJLAY_AR_525TYPE_43 3 */ |
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/*#define VIDOBJLAY_AR_625TYPE_169 8 */ |
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/*#define VIDOBJLAY_AR_525TYPE_169 9 */ |
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#define VIDOBJLAY_AR_EXTPAR 15 |
#define VIDOBJLAY_AR_EXTPAR 15 |
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#define VIDOBJLAY_SHAPE_BINARY_ONLY 2 |
#define VIDOBJLAY_SHAPE_BINARY_ONLY 2 |
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#define VIDOBJLAY_SHAPE_GRAYSCALE 3 |
#define VIDOBJLAY_SHAPE_GRAYSCALE 3 |
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#define VO_START_CODE 0x8 |
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#define VOL_START_CODE 0x12 |
#define SPRITE_NONE 0 |
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#define VOP_START_CODE 0x1b6 |
#define SPRITE_STATIC 1 |
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#define SPRITE_GMC 2 |
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#define READ_MARKER() BitstreamSkip(bs, 1) |
#define READ_MARKER() BitstreamSkip(bs, 1) |
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#define WRITE_MARKER() BitstreamPutBit(bs, 1) |
#define WRITE_MARKER() BitstreamPutBit(bs, 1) |
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// vop coding types |
/* vop coding types */ |
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// intra, prediction, backward, sprite, not_coded |
/* intra, prediction, backward, sprite, not_coded */ |
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#define I_VOP 0 |
#define I_VOP 0 |
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#define P_VOP 1 |
#define P_VOP 1 |
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#define B_VOP 2 |
#define B_VOP 2 |
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#define S_VOP 3 |
#define S_VOP 3 |
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#define N_VOP 4 |
#define N_VOP 4 |
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/* resync-specific */ |
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// header stuff |
#define NUMBITS_VP_RESYNC_MARKER 17 |
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int BitstreamReadHeaders(Bitstream * bs, DECODER * dec, uint32_t * rounding, |
#define RESYNC_MARKER 1 |
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uint32_t * quant, uint32_t * fcode, uint32_t * intra_dc_threshold); |
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/***************************************************************************** |
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* Prototypes |
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****************************************************************************/ |
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int read_video_packet_header(Bitstream *bs, |
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DECODER * dec, |
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const int addbits, |
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int *quant, |
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int *fcode_forward, |
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int *fcode_backward, |
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int *intra_dc_threshold); |
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/* header stuff */ |
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int BitstreamReadHeaders(Bitstream * bs, |
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DECODER * dec, |
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uint32_t * rounding, |
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uint32_t * quant, |
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uint32_t * fcode_forward, |
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uint32_t * fcode_backward, |
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uint32_t * intra_dc_threshold, |
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WARPPOINTS * gmc_warp); |
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void BitstreamWriteVolHeader(Bitstream * const bs, |
void BitstreamWriteVolHeader(Bitstream * const bs, |
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const MBParam * pParam); |
const MBParam * pParam, |
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const FRAMEINFO * const frame); |
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void BitstreamWriteVopHeader(Bitstream * const bs, |
void BitstreamWriteVopHeader(Bitstream * const bs, |
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const MBParam * pParam); |
const MBParam * pParam, |
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const FRAMEINFO * const frame, |
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int vop_coded, |
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unsigned int quant); |
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void BitstreamWriteUserData(Bitstream * const bs, |
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uint8_t * data, |
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const int length); |
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void |
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BitstreamWriteEndOfSequence(Bitstream * const bs); |
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void |
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BitstreamWriteGroupOfVopHeader(Bitstream * const bs, |
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const MBParam * pParam, |
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uint32_t is_closed_gov); |
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void write_video_packet_header(Bitstream * const bs, |
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const MBParam * pParam, |
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const FRAMEINFO * const frame, |
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int mbnum); |
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/* initialise bitstream structure */ |
/* initialise bitstream structure */ |
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static void __inline BitstreamInit(Bitstream * const bs, |
static void __inline |
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BitstreamInit(Bitstream * const bs, |
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void * const bitstream, |
void * const bitstream, |
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uint32_t length) |
uint32_t length) |
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{ |
{ |
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uint32_t tmp; |
uint32_t tmp; |
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size_t bitpos; |
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ptr_t adjbitstream = (ptr_t)bitstream; |
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bs->start = bs->tail = (uint32_t*)bitstream; |
/* |
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* Start the stream on a uint32_t boundary, by rounding down to the |
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* previous uint32_t and skipping the intervening bytes. |
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*/ |
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bitpos = ((sizeof(uint32_t)-1) & (size_t)bitstream); |
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adjbitstream = adjbitstream - bitpos; |
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bs->start = bs->tail = (uint32_t *) adjbitstream; |
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tmp = *(uint32_t *)bitstream; |
tmp = *bs->start; |
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#ifndef ARCH_IS_BIG_ENDIAN |
#ifndef ARCH_IS_BIG_ENDIAN |
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BSWAP(tmp); |
BSWAP(tmp); |
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#endif |
#endif |
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bs->bufa = tmp; |
bs->bufa = tmp; |
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tmp = *((uint32_t *)bitstream + 1); |
tmp = *(bs->start + 1); |
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#ifndef ARCH_IS_BIG_ENDIAN |
#ifndef ARCH_IS_BIG_ENDIAN |
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BSWAP(tmp); |
BSWAP(tmp); |
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#endif |
#endif |
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bs->bufb = tmp; |
bs->bufb = tmp; |
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bs->buf = 0; |
bs->buf = 0; |
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bs->pos = 0; |
bs->pos = bs->initpos = bitpos*8; |
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bs->length = length; |
bs->length = length; |
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} |
} |
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/* reset bitstream state */ |
/* reset bitstream state */ |
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static void __inline BitstreamReset(Bitstream * const bs) |
static void __inline |
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BitstreamReset(Bitstream * const bs) |
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{ |
{ |
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uint32_t tmp; |
uint32_t tmp; |
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bs->bufb = tmp; |
bs->bufb = tmp; |
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bs->buf = 0; |
bs->buf = 0; |
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bs->pos = 0; |
bs->pos = bs->initpos; |
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} |
} |
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/* reads n bits from bitstream without changing the stream pos */ |
/* reads n bits from bitstream without changing the stream pos */ |
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static uint32_t __inline BitstreamShowBits(Bitstream * const bs, |
static uint32_t __inline |
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BitstreamShowBits(Bitstream * const bs, |
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const uint32_t bits) |
const uint32_t bits) |
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{ |
{ |
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int nbit = (bits + bs->pos) - 32; |
int nbit = (bits + bs->pos) - 32; |
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if (nbit > 0) |
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{ |
if (nbit > 0) { |
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return ((bs->bufa & (0xffffffff >> bs->pos)) << nbit) | |
return ((bs->bufa & (0xffffffff >> bs->pos)) << nbit) | (bs-> |
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(bs->bufb >> (32 - nbit)); |
bufb >> (32 - |
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} |
nbit)); |
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else |
} else { |
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{ |
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return (bs->bufa & (0xffffffff >> bs->pos)) >> (32 - bs->pos - bits); |
return (bs->bufa & (0xffffffff >> bs->pos)) >> (32 - bs->pos - bits); |
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} |
} |
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} |
} |
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/* skip n bits forward in bitstream */ |
/* skip n bits forward in bitstream */ |
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static __inline void BitstreamSkip(Bitstream * const bs, const uint32_t bits) |
static __inline void |
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BitstreamSkip(Bitstream * const bs, |
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const uint32_t bits) |
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{ |
{ |
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bs->pos += bits; |
bs->pos += bits; |
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if (bs->pos >= 32) |
if (bs->pos >= 32) { |
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{ |
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uint32_t tmp; |
uint32_t tmp; |
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bs->bufa = bs->bufb; |
bs->bufa = bs->bufb; |
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} |
} |
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/* number of bits to next byte alignment */ |
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static __inline uint32_t |
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BitstreamNumBitsToByteAlign(Bitstream *bs) |
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{ |
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uint32_t n = (32 - bs->pos) % 8; |
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return n == 0 ? 8 : n; |
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} |
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/* show nbits from next byte alignment */ |
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static __inline uint32_t |
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BitstreamShowBitsFromByteAlign(Bitstream *bs, int bits) |
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{ |
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int bspos = bs->pos + BitstreamNumBitsToByteAlign(bs); |
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int nbit = (bits + bspos) - 32; |
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284 |
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if (bspos >= 32) { |
285 |
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return bs->bufb >> (32 - nbit); |
286 |
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} else if (nbit > 0) { |
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return ((bs->bufa & (0xffffffff >> bspos)) << nbit) | (bs-> |
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bufb >> (32 - |
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nbit)); |
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} else { |
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return (bs->bufa & (0xffffffff >> bspos)) >> (32 - bspos - bits); |
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} |
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} |
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/* move forward to the next byte boundary */ |
/* move forward to the next byte boundary */ |
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static __inline void BitstreamByteAlign(Bitstream * const bs) |
static __inline void |
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BitstreamByteAlign(Bitstream * const bs) |
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{ |
{ |
303 |
uint32_t remainder = bs->pos % 8; |
uint32_t remainder = bs->pos % 8; |
304 |
if (remainder) |
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{ |
if (remainder) { |
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BitstreamSkip(bs, 8 - remainder); |
BitstreamSkip(bs, 8 - remainder); |
307 |
} |
} |
308 |
} |
} |
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311 |
/* bitstream length (unit bits) */ |
/* bitstream length (unit bits) */ |
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static uint32_t __inline BitstreamPos(const Bitstream * const bs) |
static uint32_t __inline |
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BitstreamPos(const Bitstream * const bs) |
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{ |
{ |
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return 8 * ((uint32_t)bs->tail - (uint32_t)bs->start) + bs->pos; |
return((uint32_t)(8*((ptr_t)bs->tail - (ptr_t)bs->start) + bs->pos - bs->initpos)); |
317 |
} |
} |
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/* flush the bitstream & return length (unit bytes) |
/* |
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NOTE: assumes no futher bitstream functions will be called. |
* flush the bitstream & return length (unit bytes) |
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* NOTE: assumes no futher bitstream functions will be called. |
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*/ |
*/ |
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static uint32_t __inline BitstreamLength(Bitstream * const bs) |
static uint32_t __inline |
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BitstreamLength(Bitstream * const bs) |
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{ |
{ |
328 |
uint32_t len = (uint32_t) bs->tail - (uint32_t) bs->start; |
uint32_t len = (uint32_t)((ptr_t)bs->tail - (ptr_t)bs->start); |
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if (bs->pos) |
if (bs->pos) { |
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{ |
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uint32_t b = bs->buf; |
uint32_t b = bs->buf; |
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#ifndef ARCH_IS_BIG_ENDIAN |
#ifndef ARCH_IS_BIG_ENDIAN |
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BSWAP(b); |
BSWAP(b); |
335 |
#endif |
#endif |
338 |
len += (bs->pos + 7) / 8; |
len += (bs->pos + 7) / 8; |
339 |
} |
} |
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/* initpos is always on a byte boundary */ |
342 |
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if (bs->initpos) |
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len -= bs->initpos/8; |
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return len; |
return len; |
346 |
} |
} |
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/* move bitstream position forward by n bits and write out buffer if needed */ |
/* move bitstream position forward by n bits and write out buffer if needed */ |
350 |
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static void __inline BitstreamForward(Bitstream * const bs, const uint32_t bits) |
static void __inline |
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BitstreamForward(Bitstream * const bs, |
353 |
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const uint32_t bits) |
354 |
{ |
{ |
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bs->pos += bits; |
bs->pos += bits; |
356 |
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if (bs->pos >= 32) |
if (bs->pos >= 32) { |
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{ |
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uint32_t b = bs->buf; |
uint32_t b = bs->buf; |
359 |
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360 |
#ifndef ARCH_IS_BIG_ENDIAN |
#ifndef ARCH_IS_BIG_ENDIAN |
361 |
BSWAP(b); |
BSWAP(b); |
362 |
#endif |
#endif |
366 |
} |
} |
367 |
} |
} |
368 |
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/* pad bitstream to the next byte boundary */ |
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static void __inline BitstreamPad(Bitstream * const bs) |
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{ |
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uint32_t remainder = bs->pos % 8; |
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if (remainder) |
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{ |
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BitstreamForward(bs, 8 - remainder); |
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} |
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} |
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369 |
/* read n bits from bitstream */ |
/* read n bits from bitstream */ |
370 |
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371 |
static uint32_t __inline BitstreamGetBits(Bitstream * const bs, |
static uint32_t __inline |
372 |
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BitstreamGetBits(Bitstream * const bs, |
373 |
const uint32_t n) |
const uint32_t n) |
374 |
{ |
{ |
375 |
uint32_t ret = BitstreamShowBits(bs, n); |
uint32_t ret = BitstreamShowBits(bs, n); |
376 |
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377 |
BitstreamSkip(bs, n); |
BitstreamSkip(bs, n); |
378 |
return ret; |
return ret; |
379 |
} |
} |
381 |
|
|
382 |
/* read single bit from bitstream */ |
/* read single bit from bitstream */ |
383 |
|
|
384 |
static uint32_t __inline BitstreamGetBit(Bitstream * const bs) |
static uint32_t __inline |
385 |
|
BitstreamGetBit(Bitstream * const bs) |
386 |
{ |
{ |
387 |
return BitstreamGetBits(bs, 1); |
return BitstreamGetBits(bs, 1); |
388 |
} |
} |
390 |
|
|
391 |
/* write single bit to bitstream */ |
/* write single bit to bitstream */ |
392 |
|
|
393 |
static void __inline BitstreamPutBit(Bitstream * const bs, |
static void __inline |
394 |
|
BitstreamPutBit(Bitstream * const bs, |
395 |
const uint32_t bit) |
const uint32_t bit) |
396 |
{ |
{ |
397 |
if (bit) |
if (bit) |
403 |
|
|
404 |
/* write n bits to bitstream */ |
/* write n bits to bitstream */ |
405 |
|
|
406 |
static void __inline BitstreamPutBits(Bitstream * const bs, |
static void __inline |
407 |
|
BitstreamPutBits(Bitstream * const bs, |
408 |
const uint32_t value, |
const uint32_t value, |
409 |
const uint32_t size) |
const uint32_t size) |
410 |
{ |
{ |
428 |
} |
} |
429 |
} |
} |
430 |
|
|
431 |
|
static const int stuffing_codes[8] = |
432 |
|
{ |
433 |
|
/* nbits stuffing code */ |
434 |
|
0, /* 1 0 */ |
435 |
|
1, /* 2 01 */ |
436 |
|
3, /* 3 011 */ |
437 |
|
7, /* 4 0111 */ |
438 |
|
0xf, /* 5 01111 */ |
439 |
|
0x1f, /* 6 011111 */ |
440 |
|
0x3f, /* 7 0111111 */ |
441 |
|
0x7f, /* 8 01111111 */ |
442 |
|
}; |
443 |
|
|
444 |
|
/* pad bitstream to the next byte boundary */ |
445 |
|
|
446 |
|
static void __inline |
447 |
|
BitstreamPad(Bitstream * const bs) |
448 |
|
{ |
449 |
|
int bits = 8 - (bs->pos % 8); |
450 |
|
if (bits < 8) |
451 |
|
BitstreamPutBits(bs, stuffing_codes[bits - 1], bits); |
452 |
|
} |
453 |
|
|
454 |
|
|
455 |
|
/* |
456 |
|
* pad bitstream to the next byte boundary |
457 |
|
* alway pad: even if currently at the byte boundary |
458 |
|
*/ |
459 |
|
|
460 |
|
static void __inline |
461 |
|
BitstreamPadAlways(Bitstream * const bs) |
462 |
|
{ |
463 |
|
int bits = 8 - (bs->pos % 8); |
464 |
|
BitstreamPutBits(bs, stuffing_codes[bits - 1], bits); |
465 |
|
} |
466 |
|
|
467 |
#endif /* _BITSTREAM_H_ */ |
#endif /* _BITSTREAM_H_ */ |