/***************************************************************************** * *  XVID MPEG-4 VIDEO CODEC *  - Bitstream reader/writer inlined functions and constants- * *  Copyright (C) 2001-2003 Peter Ross <pross@xvid.org> * *  This program is free software ; you can redistribute it and/or modify *  it under the terms of the GNU General Public License as published by *  the Free Software Foundation ; either version 2 of the License, or *  (at your option) any later version. * *  This program 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 General Public License for more details. * *  You should have received a copy of the GNU General Public License *  along with this program ; if not, write to the Free Software *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA * * $Id$ * ****************************************************************************/#ifndef _BITSTREAM_H_#define _BITSTREAM_H_#include "../portab.h"#include "../decoder.h"#include "../encoder.h"/***************************************************************************** * Constants ****************************************************************************//* comment any #defs we dont use */#define VIDOBJ_START_CODE		0x00000100	/* ..0x0000011f  */#define VIDOBJLAY_START_CODE	0x00000120	/* ..0x0000012f */#define VISOBJSEQ_START_CODE	0x000001b0#define VISOBJSEQ_STOP_CODE		0x000001b1	/* ??? */#define USERDATA_START_CODE		0x000001b2#define GRPOFVOP_START_CODE		0x000001b3/*#define VIDSESERR_ERROR_CODE  0x000001b4 */#define VISOBJ_START_CODE		0x000001b5#define VOP_START_CODE			0x000001b6/*#define STUFFING_START_CODE	0x000001c3 */#define VISOBJ_TYPE_VIDEO				1/*#define VISOBJ_TYPE_STILLTEXTURE      2 *//*#define VISOBJ_TYPE_MESH              3 *//*#define VISOBJ_TYPE_FBA               4 *//*#define VISOBJ_TYPE_3DMESH            5 */#define VIDOBJLAY_TYPE_SIMPLE			1/*#define VIDOBJLAY_TYPE_SIMPLE_SCALABLE    2 *//*#define VIDOBJLAY_TYPE_CORE				3 *//*#define VIDOBJLAY_TYPE_MAIN				4 *//*#define VIDOBJLAY_TYPE_NBIT				5 *//*#define VIDOBJLAY_TYPE_ANIM_TEXT			6 *//*#define VIDOBJLAY_TYPE_ANIM_MESH			7 *//*#define VIDOBJLAY_TYPE_SIMPLE_FACE		8 *//*#define VIDOBJLAY_TYPE_STILL_SCALABLE		9 */#define VIDOBJLAY_TYPE_ART_SIMPLE		10/*#define VIDOBJLAY_TYPE_CORE_SCALABLE		11 *//*#define VIDOBJLAY_TYPE_ACE				12 *//*#define VIDOBJLAY_TYPE_ADVANCED_SCALABLE_TEXTURE 13 *//*#define VIDOBJLAY_TYPE_SIMPLE_FBA			14 *//*#define VIDEOJLAY_TYPE_SIMPLE_STUDIO    15*//*#define VIDEOJLAY_TYPE_CORE_STUDIO      16*/#define VIDOBJLAY_TYPE_ASP              17/*#define VIDOBJLAY_TYPE_FGS              18*//*#define VIDOBJLAY_AR_SQUARE           1 *//*#define VIDOBJLAY_AR_625TYPE_43       2 *//*#define VIDOBJLAY_AR_525TYPE_43       3 *//*#define VIDOBJLAY_AR_625TYPE_169      8 *//*#define VIDOBJLAY_AR_525TYPE_169      9 */#define VIDOBJLAY_AR_EXTPAR				15#define VIDOBJLAY_SHAPE_RECTANGULAR		0#define VIDOBJLAY_SHAPE_BINARY			1#define VIDOBJLAY_SHAPE_BINARY_ONLY		2#define VIDOBJLAY_SHAPE_GRAYSCALE		3#define SPRITE_NONE		0#define SPRITE_STATIC	1#define SPRITE_GMC		2#define READ_MARKER()	BitstreamSkip(bs, 1)#define WRITE_MARKER()	BitstreamPutBit(bs, 1)/* vop coding types  *//* intra, prediction, backward, sprite, not_coded */#define I_VOP	0#define P_VOP	1#define B_VOP	2#define S_VOP	3#define N_VOP	4/* resync-specific */#define NUMBITS_VP_RESYNC_MARKER  17#define RESYNC_MARKER 1/***************************************************************************** * Prototypes ****************************************************************************/int read_video_packet_header(Bitstream *bs,							 DECODER * dec,							 const int addbits,							 int *quant,							 int *fcode_forward,							 int *fcode_backward,							 int *intra_dc_threshold);/* header stuff */int BitstreamReadHeaders(Bitstream * bs,						 DECODER * dec,						 uint32_t * rounding,						 uint32_t * quant,						 uint32_t * fcode_forward,						 uint32_t * fcode_backward,						 uint32_t * intra_dc_threshold,						 WARPPOINTS * gmc_warp);void BitstreamWriteVolHeader(Bitstream * const bs,							 const MBParam * pParam,							 const FRAMEINFO * const frame);void BitstreamWriteVopHeader(Bitstream * const bs,							 const MBParam * pParam,							 const FRAMEINFO * const frame,							 int vop_coded,							 unsigned int quant);void BitstreamWriteUserData(Bitstream * const bs,							uint8_t * data,							const int length);/* initialise bitstream structure */static void __inlineBitstreamInit(Bitstream * const bs,			  void *const bitstream,			  uint32_t length){	uint32_t tmp;	size_t bitpos;	ptr_t adjbitstream = (ptr_t)bitstream;	/*	 * Start the stream on a uint32_t boundary, by rounding down to the	 * previous uint32_t and skipping the intervening bytes.	 */	bitpos = ((sizeof(uint32_t)-1) & (size_t)bitstream);	adjbitstream = adjbitstream - bitpos;	bs->start = bs->tail = (uint32_t *) adjbitstream;	tmp = *bs->start;#ifndef ARCH_IS_BIG_ENDIAN	BSWAP(tmp);#endif	bs->bufa = tmp;	tmp = *(bs->start + 1);#ifndef ARCH_IS_BIG_ENDIAN	BSWAP(tmp);#endif	bs->bufb = tmp;	bs->buf = 0;	bs->pos = bs->initpos = bitpos*8;	bs->length = length;}/* reset bitstream state */static void __inlineBitstreamReset(Bitstream * const bs){	uint32_t tmp;	bs->tail = bs->start;	tmp = *bs->start;#ifndef ARCH_IS_BIG_ENDIAN	BSWAP(tmp);#endif	bs->bufa = tmp;	tmp = *(bs->start + 1);#ifndef ARCH_IS_BIG_ENDIAN	BSWAP(tmp);#endif	bs->bufb = tmp;	bs->buf = 0;	bs->pos = bs->initpos;}/* reads n bits from bitstream without changing the stream pos */static uint32_t __inlineBitstreamShowBits(Bitstream * const bs,				  const uint32_t bits){	int nbit = (bits + bs->pos) - 32;	if (nbit > 0) {		return ((bs->bufa & (0xffffffff >> bs->pos)) << nbit) | (bs->																 bufb >> (32 -																		  nbit));	} else {		return (bs->bufa & (0xffffffff >> bs->pos)) >> (32 - bs->pos - bits);	}}/* skip n bits forward in bitstream */static __inline voidBitstreamSkip(Bitstream * const bs,			  const uint32_t bits){	bs->pos += bits;	if (bs->pos >= 32) {		uint32_t tmp;		bs->bufa = bs->bufb;		tmp = *((uint32_t *) bs->tail + 2);#ifndef ARCH_IS_BIG_ENDIAN		BSWAP(tmp);#endif		bs->bufb = tmp;		bs->tail++;		bs->pos -= 32;	}}/* number of bits to next byte alignment */static __inline uint32_tBitstreamNumBitsToByteAlign(Bitstream *bs){	uint32_t n = (32 - bs->pos) % 8;	return n == 0 ? 8 : n;}/* show nbits from next byte alignment */static __inline uint32_tBitstreamShowBitsFromByteAlign(Bitstream *bs, int bits){	int bspos = bs->pos + BitstreamNumBitsToByteAlign(bs);	int nbit = (bits + bspos) - 32;	if (bspos >= 32) {		return bs->bufb >> (32 - nbit);	} else	if (nbit > 0) {		return ((bs->bufa & (0xffffffff >> bspos)) << nbit) | (bs->																 bufb >> (32 -																		  nbit));	} else {		return (bs->bufa & (0xffffffff >> bspos)) >> (32 - bspos - bits);	}}/* move forward to the next byte boundary */static __inline voidBitstreamByteAlign(Bitstream * const bs){	uint32_t remainder = bs->pos % 8;	if (remainder) {		BitstreamSkip(bs, 8 - remainder);	}}/* bitstream length (unit bits) */static uint32_t __inlineBitstreamPos(const Bitstream * const bs){	return((uint32_t)(8*((ptr_t)bs->tail - (ptr_t)bs->start) + bs->pos - bs->initpos));}/* * flush the bitstream & return length (unit bytes) * NOTE: assumes no futher bitstream functions will be called. */static uint32_t __inlineBitstreamLength(Bitstream * const bs){	uint32_t len = (uint32_t)((ptr_t)bs->tail - (ptr_t)bs->start);	if (bs->pos) {		uint32_t b = bs->buf;#ifndef ARCH_IS_BIG_ENDIAN		BSWAP(b);#endif		*bs->tail = b;		len += (bs->pos + 7) / 8;	}	/* initpos is always on a byte boundary */	if (bs->initpos)		len -= bs->initpos/8;	return len;}/* move bitstream position forward by n bits and write out buffer if needed */static void __inlineBitstreamForward(Bitstream * const bs,				 const uint32_t bits){	bs->pos += bits;	if (bs->pos >= 32) {		uint32_t b = bs->buf;#ifndef ARCH_IS_BIG_ENDIAN		BSWAP(b);#endif		*bs->tail++ = b;		bs->buf = 0;		bs->pos -= 32;	}}/* read n bits from bitstream */static uint32_t __inlineBitstreamGetBits(Bitstream * const bs,				 const uint32_t n){	uint32_t ret = BitstreamShowBits(bs, n);	BitstreamSkip(bs, n);	return ret;}/* read single bit from bitstream */static uint32_t __inlineBitstreamGetBit(Bitstream * const bs){	return BitstreamGetBits(bs, 1);}/* write single bit to bitstream */static void __inlineBitstreamPutBit(Bitstream * const bs,				const uint32_t bit){	if (bit)		bs->buf |= (0x80000000 >> bs->pos);	BitstreamForward(bs, 1);}/* write n bits to bitstream */static void __inlineBitstreamPutBits(Bitstream * const bs,				 const uint32_t value,				 const uint32_t size){	uint32_t shift = 32 - bs->pos - size;	if (shift <= 32) {		bs->buf |= value << shift;		BitstreamForward(bs, size);	} else {		uint32_t remainder;		shift = size - (32 - bs->pos);		bs->buf |= value >> shift;		BitstreamForward(bs, size - shift);		remainder = shift;		shift = 32 - shift;		bs->buf |= value << shift;		BitstreamForward(bs, remainder);	}}static const int stuffing_codes[8] ={	        /* nbits     stuffing code */	0,		/* 1          0 */	1,		/* 2          01 */	3,		/* 3          011 */	7,		/* 4          0111 */	0xf,	/* 5          01111 */	0x1f,	/* 6          011111 */	0x3f,   /* 7          0111111 */	0x7f,	/* 8          01111111 */};/* pad bitstream to the next byte boundary */static void __inlineBitstreamPad(Bitstream * const bs){	int bits = 8 - (bs->pos % 8);	if (bits < 8)		BitstreamPutBits(bs, stuffing_codes[bits - 1], bits);}/* * pad bitstream to the next byte boundary * alway pad: even if currently at the byte boundary */static void __inlineBitstreamPadAlways(Bitstream * const bs){	int bits = 8 - (bs->pos % 8);	BitstreamPutBits(bs, stuffing_codes[bits - 1], bits);}#endif /* _BITSTREAM_H_ */