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Improve compression performance by 15-20%

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git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@55 632fc199-4ca6-4c93-a231-07263d6284db
This commit is contained in:
DRC
2009-07-30 08:35:06 +00:00
parent 5d20b7e662
commit 8443e529e9
1 changed files with 101 additions and 21 deletions
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122
jchuff.c
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@@ -33,15 +33,11 @@
#include "jinclude.h"
#include "jpeglib.h"
#include "jchuff.h" /* Declarations shared with jcphuff.c */
#include <limits.h>
static unsigned char jpeg_first_bit_table[65536];
int jpeg_first_bit_table_init=0;
#define CALC_FIRST_BIT(nbits, t) \
nbits = jpeg_first_bit_table[t&255]; \
if (t > 255) nbits = jpeg_first_bit_table[t>>8] + 8;
#ifndef min
#define min(a,b) ((a)<(b)?(a):(b))
#endif
@@ -53,7 +49,7 @@ int jpeg_first_bit_table_init=0;
*/
typedef struct {
INT32 put_buffer; /* current bit-accumulation buffer */
long put_buffer; /* current bit-accumulation buffer */
int put_bits; /* # of bits now in it */
int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
} savable_state;
@@ -185,6 +181,7 @@ start_pass_huff (j_compress_ptr cinfo, boolean gather_statistics)
}
/* Initialize bit buffer to empty */
entropy->saved.put_buffer = 0;
entropy->saved.put_bits = 0;
@@ -336,28 +333,85 @@ dump_buffer (working_state * state)
/***************************************************************/
#define EMIT_BYTE() { \
if (0xFF == (*buffer++ = put_buffer >> (put_bits -= 8))) \
*buffer++ = 0; \
}
/***************************************************************/
#define DUMP_BITS_(code, size) { \
put_bits += size; \
put_buffer = (put_buffer << size) | code; \
if (put_bits > 7) \
while(put_bits > 7) \
if (0xFF == (*buffer++ = put_buffer >> (put_bits -= 8))) \
*buffer++ = 0; \
EMIT_BYTE() \
}
/***************************************************************/
#define CHECKBUF15() { \
if (put_bits > 15) { \
EMIT_BYTE() \
EMIT_BYTE() \
} \
}
#define CHECKBUF15() { \
if (put_bits > 15) { \
EMIT_BYTE() \
EMIT_BYTE() \
} \
}
#define CHECKBUF47() { \
if (put_bits > 47) { \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
} \
}
#define CHECKBUF55() { \
if (put_bits > 55) { \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
EMIT_BYTE() \
} \
}
/***************************************************************/
#define DUMP_BITS_NOCHECK(code, size) { \
put_bits += size; \
put_buffer = (put_buffer << size) | code; \
}
#if __WORDSIZE==64
#define DUMP_BITS(code, size) { \
CHECKBUF55() \
put_bits += size; \
put_buffer = (put_buffer << size) | code; \
}
#else
#define DUMP_BITS(code, size) { \
put_bits += size; \
put_buffer = (put_buffer << size) | code; \
if (put_bits > 15) { \
if (0xFF == (*buffer++ = put_buffer >> (put_bits -= 8))) \
*buffer++ = 0; \
if (0xFF == (*buffer++ = put_buffer >> (put_bits -= 8))) \
*buffer++ = 0; \
} \
CHECKBUF15() \
}
#endif
/***************************************************************/
#define DUMP_SINGLE_VALUE(ht, codevalue) { \
@@ -369,14 +423,40 @@ dump_buffer (working_state * state)
/***************************************************************/
#define DUMP_VALUE_SLOW(ht, codevalue, t, nbits) { \
size = ht->ehufsi[codevalue]; \
code = ht->ehufco[codevalue]; \
t &= ~(-1 << nbits); \
DUMP_BITS_NOCHECK(code, size) \
CHECKBUF15() \
DUMP_BITS_NOCHECK(t, nbits) \
CHECKBUF15() \
}
#if __WORDSIZE==64
#define DUMP_VALUE(ht, codevalue, t, nbits) { \
size = ht->ehufsi[codevalue]; \
code = ht->ehufco[codevalue]; \
t &= ~(-1 << nbits); \
DUMP_BITS(code, size) \
DUMP_BITS(t, nbits) \
CHECKBUF47() \
DUMP_BITS_NOCHECK(code, size) \
DUMP_BITS_NOCHECK(t, nbits) \
}
#else
#define DUMP_VALUE(ht, codevalue, t, nbits) { \
size = ht->ehufsi[codevalue]; \
code = ht->ehufco[codevalue]; \
t &= ~(-1 << nbits); \
DUMP_BITS_NOCHECK(code, size) \
DUMP_BITS_NOCHECK(t, nbits) \
CHECKBUF15() \
}
#endif
/***************************************************************/
#define BUFSIZE (DCTSIZE2 * 2)
@@ -416,7 +496,7 @@ LOCAL(boolean)
flush_bits (working_state * state)
{
unsigned char _buffer[BUFSIZE], *buffer;
int put_buffer, put_bits;
long put_buffer; int put_bits;
int bytes, bytestocopy, localbuf = 0;
put_buffer = state->cur.put_buffer;
@@ -442,7 +522,7 @@ encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,
int nbits;
int r, sflag, size, code;
unsigned char _buffer[BUFSIZE], *buffer;
int put_buffer, put_bits;
long put_buffer; int put_bits;
int code_0xf0 = actbl->ehufco[0xf0], size_0xf0 = actbl->ehufsi[0xf0];
int bytes, bytestocopy, localbuf = 0;
@@ -457,8 +537,8 @@ encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,
sflag = temp >> 31;
temp -= ((temp + temp) & sflag);
temp2 += sflag;
CALC_FIRST_BIT(nbits, temp)
DUMP_VALUE(dctbl, nbits, temp2, nbits)
nbits = jpeg_first_bit_table[temp];
DUMP_VALUE_SLOW(dctbl, nbits, temp2, nbits)
/* Encode the AC coefficients per section F.1.2.2 */
@@ -472,8 +552,8 @@ encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,
sflag = temp >> 31; \
temp = (temp ^ sflag) - sflag; \
temp2 += sflag; \
nbits = jpeg_first_bit_table[temp]; \
for(; r > 15; r -= 16) DUMP_BITS(code_0xf0, size_0xf0) \
nbits = jpeg_first_bit_table[temp]; \
sflag = (r << 4) + nbits; \
DUMP_VALUE(actbl, sflag, temp2, nbits) \
r = 0; \