| 178 |
int m_Mpeg4SequenceSize; |
int m_Mpeg4SequenceSize; |
| 179 |
}; |
}; |
| 180 |
|
|
| 181 |
|
|
| 182 |
|
/***************************************************************************** |
| 183 |
|
* Bitstream helper functions |
| 184 |
|
****************************************************************************/ |
| 185 |
|
|
| 186 |
|
/* Copied from bitstream.h of xvidcore - TODO: BAD... |
| 187 |
|
/* Copyright (C) 2001-2003 Peter Ross <pross@xvid.org> */ |
| 188 |
|
|
| 189 |
|
/* Input buffer should be readable as full chunks of 8bytes, including |
| 190 |
|
the end of the buffer. Padding might be appropriate. If only chunks |
| 191 |
|
of 4bytes are applicable, define XVID_SAFE_BS_TAIL. Note that this will |
| 192 |
|
slow decoding, so consider this as a last-resort solution */ |
| 193 |
|
|
| 194 |
|
/* #define XVID_SAFE_BS_TAIL */ |
| 195 |
|
|
| 196 |
|
#define BSWAP(a) __asm mov eax,a __asm bswap eax __asm mov a, eax |
| 197 |
|
|
| 198 |
|
#define VIDOBJLAY_START_CODE_MASK 0x0000000f |
| 199 |
|
#define VIDOBJLAY_START_CODE 0x00000120 /* ..0x0000012f */ |
| 200 |
|
#define VISOBJ_START_CODE 0x000001b5 |
| 201 |
|
|
| 202 |
|
#define VIDOBJLAY_SHAPE_RECTANGULAR 0 |
| 203 |
|
#define VISOBJ_TYPE_VIDEO 1 |
| 204 |
|
#define VIDOBJLAY_AR_EXTPAR 15 |
| 205 |
|
|
| 206 |
|
#define READ_MARKER() BitstreamSkip(bs, 1) |
| 207 |
|
|
| 208 |
|
#define MAX(a, b) ((a > b) ? (a) : (b)) |
| 209 |
|
|
| 210 |
|
|
| 211 |
|
typedef struct |
| 212 |
|
{ |
| 213 |
|
unsigned int bufa; |
| 214 |
|
unsigned int bufb; |
| 215 |
|
unsigned int buf; |
| 216 |
|
unsigned int pos; |
| 217 |
|
unsigned int *tail; |
| 218 |
|
unsigned int *start; |
| 219 |
|
unsigned int length; |
| 220 |
|
unsigned int initpos; |
| 221 |
|
} |
| 222 |
|
Bitstream; |
| 223 |
|
|
| 224 |
|
|
| 225 |
|
/* initialise bitstream structure */ |
| 226 |
|
|
| 227 |
|
static void __inline |
| 228 |
|
BitstreamInit(Bitstream * const bs, |
| 229 |
|
void *const bitstream, |
| 230 |
|
unsigned int length) |
| 231 |
|
{ |
| 232 |
|
unsigned int tmp; |
| 233 |
|
size_t bitpos; |
| 234 |
|
unsigned int adjbitstream = (unsigned int)bitstream; |
| 235 |
|
|
| 236 |
|
/* |
| 237 |
|
* Start the stream on a uint32_t boundary, by rounding down to the |
| 238 |
|
* previous uint32_t and skipping the intervening bytes. |
| 239 |
|
*/ |
| 240 |
|
bitpos = ((sizeof(unsigned int)-1) & (size_t)bitstream); |
| 241 |
|
adjbitstream = adjbitstream - bitpos; |
| 242 |
|
bs->start = bs->tail = (unsigned int *) adjbitstream; |
| 243 |
|
|
| 244 |
|
tmp = *bs->start; |
| 245 |
|
#ifndef ARCH_IS_BIG_ENDIAN |
| 246 |
|
BSWAP(tmp); |
| 247 |
|
#endif |
| 248 |
|
bs->bufa = tmp; |
| 249 |
|
|
| 250 |
|
tmp = *(bs->start + 1); |
| 251 |
|
#ifndef ARCH_IS_BIG_ENDIAN |
| 252 |
|
BSWAP(tmp); |
| 253 |
|
#endif |
| 254 |
|
bs->bufb = tmp; |
| 255 |
|
|
| 256 |
|
bs->pos = bs->initpos = (unsigned int) bitpos*8; |
| 257 |
|
/* preserve the intervening bytes */ |
| 258 |
|
if (bs->initpos > 0) |
| 259 |
|
bs->buf = bs->bufa & (0xffffffff << (32 - bs->initpos)); |
| 260 |
|
else |
| 261 |
|
bs->buf = 0; |
| 262 |
|
bs->length = length; |
| 263 |
|
} |
| 264 |
|
|
| 265 |
|
|
| 266 |
|
/* reads n bits from bitstream without changing the stream pos */ |
| 267 |
|
|
| 268 |
|
static unsigned int __inline |
| 269 |
|
BitstreamShowBits(Bitstream * const bs, |
| 270 |
|
const unsigned int bits) |
| 271 |
|
{ |
| 272 |
|
int nbit = (bits + bs->pos) - 32; |
| 273 |
|
|
| 274 |
|
if (nbit > 0) { |
| 275 |
|
return ((bs->bufa & (0xffffffff >> bs->pos)) << nbit) | (bs-> |
| 276 |
|
bufb >> (32 - |
| 277 |
|
nbit)); |
| 278 |
|
} else { |
| 279 |
|
return (bs->bufa & (0xffffffff >> bs->pos)) >> (32 - bs->pos - bits); |
| 280 |
|
} |
| 281 |
|
} |
| 282 |
|
|
| 283 |
|
|
| 284 |
|
/* skip n bits forward in bitstream */ |
| 285 |
|
|
| 286 |
|
static __inline void |
| 287 |
|
BitstreamSkip(Bitstream * const bs, |
| 288 |
|
const unsigned int bits) |
| 289 |
|
{ |
| 290 |
|
bs->pos += bits; |
| 291 |
|
|
| 292 |
|
if (bs->pos >= 32) { |
| 293 |
|
unsigned int tmp; |
| 294 |
|
|
| 295 |
|
bs->bufa = bs->bufb; |
| 296 |
|
#if defined(XVID_SAFE_BS_TAIL) |
| 297 |
|
if (bs->tail<(bs->start+((bs->length+3)>>2))) |
| 298 |
|
#endif |
| 299 |
|
{ |
| 300 |
|
tmp = *((unsigned int *) bs->tail + 2); |
| 301 |
|
#ifndef ARCH_IS_BIG_ENDIAN |
| 302 |
|
BSWAP(tmp); |
| 303 |
|
#endif |
| 304 |
|
bs->bufb = tmp; |
| 305 |
|
bs->tail++; |
| 306 |
|
} |
| 307 |
|
#if defined(XVID_SAFE_BS_TAIL) |
| 308 |
|
else { |
| 309 |
|
bs->bufb = 0; |
| 310 |
|
} |
| 311 |
|
#endif |
| 312 |
|
bs->pos -= 32; |
| 313 |
|
} |
| 314 |
|
} |
| 315 |
|
|
| 316 |
|
|
| 317 |
|
/* move forward to the next byte boundary */ |
| 318 |
|
|
| 319 |
|
static __inline void |
| 320 |
|
BitstreamByteAlign(Bitstream * const bs) |
| 321 |
|
{ |
| 322 |
|
unsigned int remainder = bs->pos % 8; |
| 323 |
|
|
| 324 |
|
if (remainder) { |
| 325 |
|
BitstreamSkip(bs, 8 - remainder); |
| 326 |
|
} |
| 327 |
|
} |
| 328 |
|
|
| 329 |
|
|
| 330 |
|
/* bitstream length (unit bits) */ |
| 331 |
|
|
| 332 |
|
static unsigned int __inline |
| 333 |
|
BitstreamPos(const Bitstream * const bs) |
| 334 |
|
{ |
| 335 |
|
return((unsigned int)(8*((unsigned int)bs->tail - (unsigned int)bs->start) + bs->pos - bs->initpos)); |
| 336 |
|
} |
| 337 |
|
|
| 338 |
|
|
| 339 |
|
/* read n bits from bitstream */ |
| 340 |
|
|
| 341 |
|
static unsigned int __inline |
| 342 |
|
BitstreamGetBits(Bitstream * const bs, |
| 343 |
|
const unsigned int n) |
| 344 |
|
{ |
| 345 |
|
unsigned int ret = BitstreamShowBits(bs, n); |
| 346 |
|
|
| 347 |
|
BitstreamSkip(bs, n); |
| 348 |
|
return ret; |
| 349 |
|
} |
| 350 |
|
|
| 351 |
|
|
| 352 |
|
/* read single bit from bitstream */ |
| 353 |
|
|
| 354 |
|
static unsigned int __inline |
| 355 |
|
BitstreamGetBit(Bitstream * const bs) |
| 356 |
|
{ |
| 357 |
|
return BitstreamGetBits(bs, 1); |
| 358 |
|
} |
| 359 |
|
|
| 360 |
|
/*****************************************************************************/ |
| 361 |
|
|
| 362 |
#endif /* _FILTERS_H_ */ |
#endif /* _FILTERS_H_ */ |
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