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mpgplyr1.lha
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util.h
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C/C++ Source or Header
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1992-12-08
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19KB
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329 lines
/*
* Copyright (c) 1992 The Regents of the University of California.
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose, without fee, and without written agreement is
* hereby granted, provided that the above copyright notice and the following
* two paragraphs appear in all copies of this software.
*
* IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
* CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
/* Status codes for bit stream i/o operations. */
#define NO_VID_STREAM -1
#define UNDERFLOW -2
#define OK 1
/* Size increment of extension data buffers. */
#define EXT_BUF_SIZE 1024
/* External declarations for bitstream i/o operations. */
extern unsigned int bitMask[];
extern unsigned int nBitMask[];
extern unsigned int rBitMask[];
extern unsigned int bitTest[];
extern int next_bits();
extern char *get_ext_data();
extern int next_start_code();
extern char *get_extra_bit_info();
/* External declarations of bitstream global variables. */
extern unsigned int curBits;
extern int bitOffset;
extern int bufLength;
extern unsigned int *bitBuffer;
/* Macro for updating bit counter if analysis tool is on. */
#ifdef ANALYSIS
#define UPDATE_COUNT(numbits) bitCount += numbits
#else
#define UPDATE_COUNT(numbits)
#endif
#ifdef NO_SANITY_CHECKS
#define get_bits1(result) \
{ \
UPDATE_COUNT(1); \
if (bitOffset < 31) { \
*(result) = ((curBits & bitTest[bitOffset]) != 0); \
bitOffset++; \
} \
else { \
*(result) = (curBits & 0x00000001); \
bitOffset = 0; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
}
#define get_bits2(result) \
{ \
UPDATE_COUNT(2) \
if (bitOffset < 30) { \
*(result) = ((curBits & bitMask[bitOffset]) >> \
(30-bitOffset)); \
bitOffset += 2; \
} \
else if (bitOffset == 30) { \
*(result) = (curBits & 0x00000003); \
bitOffset = 0; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
else { \
*(result) = (((curBits & 0x01) << 1) | \
((*(bitBuffer+1) & 0x80000000) != 0)); \
bitOffset = 1; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
}
#define get_bitsX(num, thresh, result) \
{ \
int OFFnum = (bitOffset - thresh); \
\
UPDATE_COUNT(num); \
\
if (OFFnum < 0) { \
*(result) = ((curBits & bitMask[bitOffset]) >> (-OFFnum)); \
bitOffset += num; \
} else if (OFFnum == 0) { \
*(result) = (curBits & bitMask[bitOffset]) << OFFnum; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset = 0; \
} else { \
*(result) = (((curBits & bitMask[bitOffset]) << OFFnum) | \
((*(bitBuffer+1) & (nBitMask[OFFnum])) >> (32-OFFnum))); \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset = OFFnum; \
} \
}
#else
#define get_bits1(result) \
{ \
\
/* Check for underflow. */ \
\
if (bufLength < 2) { \
correct_underflow(); \
} \
UPDATE_COUNT(1); \
\
if (bitOffset < 31) { \
*(result) = ((curBits & bitTest[bitOffset]) != 0); \
bitOffset++; \
} \
else { \
*(result) = (curBits & 0x00000001); \
bitOffset = 0; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
}
#define get_bits2(result) \
{ \
\
/* Check for underflow. */ \
\
if (bufLength < 2) { \
correct_underflow(); \
} \
UPDATE_COUNT(2); \
\
if (bitOffset < 30) { \
*(result) = ((curBits & bitMask[bitOffset]) >> \
(30-bitOffset)); \
bitOffset += 2; \
} \
else if (bitOffset == 30) { \
*(result) = (curBits & 0x00000003); \
bitOffset = 0; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
else { \
*(result) = (((curBits & 0x01) << 1) | \
((*(bitBuffer+1) & 0x80000000) != 0)); \
bitOffset = 1; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
} \
}
#define get_bitsX(num, thresh, result) \
{ \
int OFFnum = (bitOffset - thresh); \
\
/* Check for underflow. */ \
\
if (bufLength < 2) { \
correct_underflow(); \
} \
UPDATE_COUNT(num); \
\
if (OFFnum < 0) { \
*(result) = ((curBits & bitMask[bitOffset]) >> (-OFFnum)); \
bitOffset += num; \
} else if (OFFnum == 0) { \
*(result) = (curBits & bitMask[bitOffset]) << OFFnum; \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset = 0; \
} else { \
*(result) = (((curBits & bitMask[bitOffset]) << OFFnum) | \
((*(bitBuffer+1) & (nBitMask[OFFnum])) >> (32-OFFnum))); \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset = OFFnum; \
} \
}
#endif
#define get_bits3(result) get_bitsX(3, 29, result)
#define get_bits4(result) get_bitsX(4, 28, result)
#define get_bits5(result) get_bitsX(5, 27, result)
#define get_bits6(result) get_bitsX(6, 26, result)
#define get_bits7(result) get_bitsX(7, 25, result)
#define get_bits8(result) get_bitsX(8, 24, result)
#define get_bits9(result) get_bitsX(9, 23, result)
#define get_bits10(result) get_bitsX(10, 22, result)
#define get_bits11(result) get_bitsX(11, 21, result)
#define get_bits12(result) get_bitsX(12, 20, result)
#define get_bits16(result) get_bitsX(16, 16, result)
#define get_bits18(result) get_bitsX(18, 14, result)
#define get_bits32(result) get_bitsX(32, 0, result)
#define get_bitsn(num, result) get_bitsX((num),(32-(num)),result)
#ifdef NO_SANITY_CHECKS
#define show_bitsX(num, thresh, result) \
{ \
int OFFnum = (bitOffset - thresh); \
\
if (OFFnum <= 0) { \
*(result) = ((curBits & bitMask[bitOffset]) >> (-OFFnum)); \
} else { \
*(result) = (((curBits & bitMask[bitOffset]) << OFFnum) | \
((*(bitBuffer+1) & (nBitMask[OFFnum])) >> (32-OFFnum))); \
} \
}
#else
#define show_bitsX(num, thresh, result) \
{ \
int OFFnum = (bitOffset - thresh); \
\
/* Check for underflow. */ \
if (bufLength < 2) { \
correct_underflow(); \
} \
\
if (OFFnum <= 0) { \
*(result) = ((curBits & bitMask[bitOffset]) >> (-OFFnum)); \
} else { \
*(result) = (((curBits & bitMask[bitOffset]) << OFFnum) | \
((*(bitBuffer+1) & (nBitMask[OFFnum])) >> (32-OFFnum))); \
} \
}
#endif
#define show_bits1(result) show_bitsX(1, 31, result)
#define show_bits2(result) show_bitsX(2, 30, result)
#define show_bits3(result) show_bitsX(3, 29, result)
#define show_bits4(result) show_bitsX(4, 28, result)
#define show_bits5(result) show_bitsX(5, 27, result)
#define show_bits6(result) show_bitsX(6, 26, result)
#define show_bits7(result) show_bitsX(7, 25, result)
#define show_bits8(result) show_bitsX(8, 24, result)
#define show_bits9(result) show_bitsX(9, 23, result)
#define show_bits10(result) show_bitsX(10, 22, result)
#define show_bits11(result) show_bitsX(11, 21, result)
#define show_bits12(result) show_bitsX(12, 20, result)
#define show_bits13(result) show_bitsX(13, 19, result)
#define show_bits14(result) show_bitsX(14, 18, result)
#define show_bits15(result) show_bitsX(15, 17, result)
#define show_bits16(result) show_bitsX(16, 16, result)
#define show_bits17(result) show_bitsX(17, 15, result)
#define show_bits18(result) show_bitsX(18, 14, result)
#define show_bits19(result) show_bitsX(19, 13, result)
#define show_bits20(result) show_bitsX(20, 12, result)
#define show_bits21(result) show_bitsX(21, 11, result)
#define show_bits22(result) show_bitsX(22, 10, result)
#define show_bits23(result) show_bitsX(23, 9, result)
#define show_bits24(result) show_bitsX(24, 8, result)
#define show_bits25(result) show_bitsX(25, 7, result)
#define show_bits26(result) show_bitsX(26, 6, result)
#define show_bits27(result) show_bitsX(27, 5, result)
#define show_bits28(result) show_bitsX(28, 4, result)
#define show_bits29(result) show_bitsX(29, 3, result)
#define show_bits30(result) show_bitsX(30, 2, result)
#define show_bits31(result) show_bitsX(31, 1, result)
#define show_bits32(result) show_bitsX(32, 0, result)
#define show_bitsn(num,result) show_bitsX((num),(32-(num)),result)
#ifdef NO_SANITY_CHECKS
#define flush_bits(num) \
{ \
bitOffset += num; \
\
UPDATE_COUNT(num); \
\
if (bitOffset > 31) { \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset -= 32; \
} \
}
#else
#define flush_bits(num) \
{ \
if (curVidStream == NULL) { \
/* Deal with no vid stream here. */ \
} \
\
if (bufLength < 2) { \
correct_underflow(); \
} \
\
UPDATE_COUNT(num); \
\
bitOffset += num; \
\
if (bitOffset > 31) { \
bitBuffer++; \
curBits = *bitBuffer; \
bufLength--; \
bitOffset -= 32; \
} \
}
#endif