1575 lines
44 KiB
C++
1575 lines
44 KiB
C++
#include "stdafx.h"
|
|
#pragma hdrstop
|
|
|
|
/*
|
|
* jdhuff.c
|
|
*
|
|
* Copyright (C) 1991-1996, Thomas G. Lane.
|
|
* This file is part of the Independent JPEG Group's software.
|
|
* For conditions of distribution and use, see the accompanying README file.
|
|
*
|
|
* This file contains Huffman entropy decoding routines.
|
|
*
|
|
* Much of the complexity here has to do with supporting input suspension.
|
|
* If the data source module demands suspension, we want to be able to back
|
|
* up to the start of the current MCU. To do this, we copy state variables
|
|
* into local working storage, and update them back to the permanent
|
|
* storage only upon successful completion of an MCU.
|
|
*/
|
|
|
|
#define JPEG_INTERNALS
|
|
#include "jinclude.h"
|
|
#include "jpeglib.h"
|
|
#include "jdhuff.h" /* Declarations shared with jdphuff.c */
|
|
|
|
#ifdef _M_IX86
|
|
#pragma warning(disable:4799)
|
|
#endif
|
|
|
|
/*
|
|
* Expanded entropy decoder object for Huffman decoding.
|
|
*
|
|
* The savable_state subrecord contains fields that change within an MCU,
|
|
* but must not be updated permanently until we complete the MCU.
|
|
*/
|
|
|
|
typedef struct {
|
|
int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
|
|
} savable_state;
|
|
|
|
/* This macro is to work around compilers with missing or broken
|
|
* structure assignment. You'll need to fix this code if you have
|
|
* such a compiler and you change MAX_COMPS_IN_SCAN.
|
|
*/
|
|
|
|
#ifndef NO_STRUCT_ASSIGN
|
|
#define ASSIGN_STATE(dest,src) ((dest) = (src))
|
|
#else
|
|
#if MAX_COMPS_IN_SCAN == 4
|
|
#define ASSIGN_STATE(dest,src) \
|
|
((dest).last_dc_val[0] = (src).last_dc_val[0], \
|
|
(dest).last_dc_val[1] = (src).last_dc_val[1], \
|
|
(dest).last_dc_val[2] = (src).last_dc_val[2], \
|
|
(dest).last_dc_val[3] = (src).last_dc_val[3])
|
|
#endif
|
|
#endif
|
|
|
|
|
|
typedef struct {
|
|
struct jpeg_entropy_decoder pub; /* public fields */
|
|
|
|
/* These fields are loaded into local variables at start of each MCU.
|
|
* In case of suspension, we exit WITHOUT updating them.
|
|
*/
|
|
bitread_perm_state bitstate; /* Bit buffer at start of MCU */
|
|
savable_state saved; /* Other state at start of MCU */
|
|
|
|
/* These fields are NOT loaded into local working state. */
|
|
unsigned int restarts_to_go; /* MCUs left in this restart interval */
|
|
|
|
/* Pointers to derived tables (these workspaces have image lifespan) */
|
|
d_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];
|
|
d_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];
|
|
} huff_entropy_decoder;
|
|
|
|
typedef huff_entropy_decoder * huff_entropy_ptr;
|
|
|
|
|
|
/*
|
|
* Initialize for a Huffman-compressed scan.
|
|
*/
|
|
|
|
METHODDEF(void)
|
|
start_pass_huff_decoder (j_decompress_ptr cinfo)
|
|
{
|
|
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
|
|
int ci, dctbl, actbl;
|
|
jpeg_component_info * compptr;
|
|
|
|
/* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG.
|
|
* This ought to be an error condition, but we make it a warning because
|
|
* there are some baseline files out there with all zeroes in these bytes.
|
|
*/
|
|
if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 ||
|
|
cinfo->Ah != 0 || cinfo->Al != 0)
|
|
WARNMS(cinfo, JWRN_NOT_SEQUENTIAL);
|
|
|
|
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
|
|
compptr = cinfo->cur_comp_info[ci];
|
|
dctbl = compptr->dc_tbl_no;
|
|
actbl = compptr->ac_tbl_no;
|
|
/* Make sure requested tables are present */
|
|
if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS ||
|
|
cinfo->dc_huff_tbl_ptrs[dctbl] == NULL)
|
|
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);
|
|
if (actbl < 0 || actbl >= NUM_HUFF_TBLS ||
|
|
cinfo->ac_huff_tbl_ptrs[actbl] == NULL)
|
|
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl);
|
|
/* Compute derived values for Huffman tables */
|
|
/* We may do this more than once for a table, but it's not expensive */
|
|
jpeg_make_d_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[dctbl],
|
|
& entropy->dc_derived_tbls[dctbl]);
|
|
jpeg_make_d_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[actbl],
|
|
& entropy->ac_derived_tbls[actbl]);
|
|
/* Initialize DC predictions to 0 */
|
|
entropy->saved.last_dc_val[ci] = 0;
|
|
}
|
|
|
|
/* Initialize bitread state variables */
|
|
entropy->bitstate.bits_left = 0;
|
|
entropy->bitstate.get_buffer_64 = 0;
|
|
entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
|
|
entropy->bitstate.printed_eod = FALSE;
|
|
|
|
/* Initialize restart counter */
|
|
entropy->restarts_to_go = cinfo->restart_interval;
|
|
}
|
|
|
|
|
|
/*
|
|
* Compute the derived values for a Huffman table.
|
|
* Note this is also used by jdphuff.c.
|
|
*/
|
|
|
|
GLOBAL(void)
|
|
jpeg_make_d_derived_tbl (j_decompress_ptr cinfo, JHUFF_TBL * htbl,
|
|
d_derived_tbl ** pdtbl)
|
|
{
|
|
d_derived_tbl *dtbl;
|
|
int p, i, l, si;
|
|
int lookbits, ctr;
|
|
char huffsize[257];
|
|
unsigned int huffcode[257];
|
|
unsigned int code;
|
|
|
|
/* Allocate a workspace if we haven't already done so. */
|
|
if (*pdtbl == NULL)
|
|
*pdtbl = (d_derived_tbl *)
|
|
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
|
SIZEOF(d_derived_tbl));
|
|
dtbl = *pdtbl;
|
|
dtbl->pub = htbl; /* fill in back link */
|
|
|
|
/* Figure C.1: make table of Huffman code length for each symbol */
|
|
/* Note that this is in code-length order. */
|
|
|
|
p = 0;
|
|
for (l = 1; l <= 16; l++) {
|
|
for (i = 1; i <= (int) htbl->bits[l]; i++)
|
|
huffsize[p++] = (char) l;
|
|
}
|
|
huffsize[p] = 0;
|
|
|
|
/* Figure C.2: generate the codes themselves */
|
|
/* Note that this is in code-length order. */
|
|
|
|
code = 0;
|
|
si = huffsize[0];
|
|
p = 0;
|
|
while (huffsize[p]) {
|
|
while (((int) huffsize[p]) == si) {
|
|
huffcode[p++] = code;
|
|
code++;
|
|
}
|
|
code <<= 1;
|
|
si++;
|
|
}
|
|
|
|
/* Figure F.15: generate decoding tables for bit-sequential decoding */
|
|
|
|
p = 0;
|
|
for (l = 1; l <= 16; l++) {
|
|
if (htbl->bits[l]) {
|
|
dtbl->valptr[l] = p; /* huffval[] index of 1st symbol of code length l */
|
|
dtbl->mincode[l] = huffcode[p]; /* minimum code of length l */
|
|
p += htbl->bits[l];
|
|
dtbl->maxcode[l] = huffcode[p-1]; /* maximum code of length l */
|
|
} else {
|
|
dtbl->maxcode[l] = -1; /* -1 if no codes of this length */
|
|
}
|
|
}
|
|
dtbl->maxcode[17] = 0xFFFFFL; /* ensures jpeg_huff_decode terminates */
|
|
|
|
/* Compute lookahead tables to speed up decoding.
|
|
* First we set all the table entries to 0, indicating "too long";
|
|
* then we iterate through the Huffman codes that are short enough and
|
|
* fill in all the entries that correspond to bit sequences starting
|
|
* with that code.
|
|
*/
|
|
|
|
MEMZERO(dtbl->look_nbits, SIZEOF(dtbl->look_nbits));
|
|
|
|
p = 0;
|
|
for (l = 1; l <= HUFF_LOOKAHEAD; l++) {
|
|
for (i = 1; i <= (int) htbl->bits[l]; i++, p++) {
|
|
/* l = current code's length, p = its index in huffcode[] & huffval[]. */
|
|
/* Generate left-justified code followed by all possible bit sequences */
|
|
lookbits = huffcode[p] << (HUFF_LOOKAHEAD-l);
|
|
for (ctr = 1 << (HUFF_LOOKAHEAD-l); ctr > 0; ctr--) {
|
|
dtbl->look_nbits[lookbits] = l;
|
|
dtbl->look_sym[lookbits] = htbl->huffval[p];
|
|
lookbits++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Out-of-line code for bit fetching (shared with jdphuff.c).
|
|
* See jdhuff.h for info about usage.
|
|
* Note: current values of get_buffer and bits_left are passed as parameters,
|
|
* but are returned in the corresponding fields of the state struct.
|
|
*
|
|
* On most machines MIN_GET_BITS should be 25 to allow the full 32-bit width
|
|
* of get_buffer to be used. (On machines with wider words, an even larger
|
|
* buffer could be used.) However, on some machines 32-bit shifts are
|
|
* quite slow and take time proportional to the number of places shifted.
|
|
* (This is true with most PC compilers, for instance.) In this case it may
|
|
* be a win to set MIN_GET_BITS to the minimum value of 15. This reduces the
|
|
* average shift distance at the cost of more calls to jpeg_fill_bit_buffer.
|
|
*/
|
|
|
|
#ifdef SLOW_SHIFT_32
|
|
#define MIN_GET_BITS 15 /* minimum allowable value */
|
|
#else
|
|
#define MIN_GET_BITS (BIT_BUF_SIZE-7)
|
|
#endif
|
|
|
|
// not used in MMX version
|
|
GLOBAL(boolean)
|
|
jpeg_fill_bit_buffer (bitread_working_state * state,
|
|
register bit_buf_type get_buffer, register int bits_left,
|
|
int nbits)
|
|
/* Load up the bit buffer to a depth of at least nbits */
|
|
{
|
|
/* Copy heavily used state fields into locals (hopefully registers) */
|
|
register const JOCTET * next_input_byte = state->next_input_byte;
|
|
register size_t bytes_in_buffer = state->bytes_in_buffer;
|
|
register int c;
|
|
|
|
/* Attempt to load at least MIN_GET_BITS bits into get_buffer. */
|
|
/* (It is assumed that no request will be for more than that many bits.) */
|
|
|
|
while (bits_left < MIN_GET_BITS) {
|
|
/* Attempt to read a byte */
|
|
if (state->unread_marker != 0)
|
|
goto no_more_data; /* can't advance past a marker */
|
|
|
|
if (bytes_in_buffer == 0) {
|
|
if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))
|
|
return FALSE;
|
|
next_input_byte = state->cinfo->src->next_input_byte;
|
|
bytes_in_buffer = state->cinfo->src->bytes_in_buffer;
|
|
}
|
|
bytes_in_buffer--;
|
|
c = GETJOCTET(*next_input_byte++);
|
|
|
|
/* If it's 0xFF, check and discard stuffed zero byte */
|
|
if (c == 0xFF) {
|
|
do {
|
|
if (bytes_in_buffer == 0) {
|
|
if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))
|
|
return FALSE;
|
|
next_input_byte = state->cinfo->src->next_input_byte;
|
|
bytes_in_buffer = state->cinfo->src->bytes_in_buffer;
|
|
}
|
|
bytes_in_buffer--;
|
|
c = GETJOCTET(*next_input_byte++);
|
|
} while (c == 0xFF);
|
|
|
|
if (c == 0) {
|
|
/* Found FF/00, which represents an FF data byte */
|
|
c = 0xFF;
|
|
} else {
|
|
/* Oops, it's actually a marker indicating end of compressed data. */
|
|
/* Better put it back for use later */
|
|
state->unread_marker = c;
|
|
|
|
no_more_data:
|
|
/* There should be enough bits still left in the data segment; */
|
|
/* if so, just break out of the outer while loop. */
|
|
if (bits_left >= nbits)
|
|
break;
|
|
/* Uh-oh. Report corrupted data to user and stuff zeroes into
|
|
* the data stream, so that we can produce some kind of image.
|
|
* Note that this code will be repeated for each byte demanded
|
|
* for the rest of the segment. We use a nonvolatile flag to ensure
|
|
* that only one warning message appears.
|
|
*/
|
|
if (! *(state->printed_eod_ptr)) {
|
|
WARNMS(state->cinfo, JWRN_HIT_MARKER);
|
|
*(state->printed_eod_ptr) = TRUE;
|
|
}
|
|
c = 0; /* insert a zero byte into bit buffer */
|
|
}
|
|
}
|
|
|
|
/* OK, load c into get_buffer */
|
|
get_buffer = (get_buffer << 8) | c;
|
|
bits_left += 8;
|
|
}
|
|
|
|
/* Unload the local registers */
|
|
state->next_input_byte = next_input_byte;
|
|
state->bytes_in_buffer = bytes_in_buffer;
|
|
state->get_buffer = get_buffer;
|
|
state->bits_left = bits_left;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
|
|
/*
|
|
* Out-of-line code for Huffman code decoding.
|
|
* See jdhuff.h for info about usage.
|
|
*/
|
|
|
|
GLOBAL(int)
|
|
jpeg_huff_decode (bitread_working_state * state,
|
|
register bit_buf_type get_buffer, register int bits_left,
|
|
d_derived_tbl * htbl, int min_bits)
|
|
{
|
|
register int l = min_bits;
|
|
register INT32 code;
|
|
|
|
/* HUFF_DECODE has determined that the code is at least min_bits */
|
|
/* bits long, so fetch that many bits in one swoop. */
|
|
|
|
CHECK_BIT_BUFFER(*state, l, return -1);
|
|
code = GET_BITS(l);
|
|
|
|
/* Collect the rest of the Huffman code one bit at a time. */
|
|
/* This is per Figure F.16 in the JPEG spec. */
|
|
|
|
while (code > htbl->maxcode[l]) {
|
|
code <<= 1;
|
|
CHECK_BIT_BUFFER(*state, 1, return -1);
|
|
code |= GET_BITS(1);
|
|
l++;
|
|
}
|
|
|
|
/* Unload the local registers */
|
|
state->get_buffer = get_buffer;
|
|
state->bits_left = bits_left;
|
|
|
|
/* With garbage input we may reach the sentinel value l = 17. */
|
|
|
|
if (l > 16) {
|
|
WARNMS(state->cinfo, JWRN_HUFF_BAD_CODE);
|
|
return 0; /* fake a zero as the safest result */
|
|
}
|
|
|
|
return htbl->pub->huffval[ htbl->valptr[l] +
|
|
((int) (code - htbl->mincode[l])) ];
|
|
}
|
|
|
|
|
|
/*
|
|
* Figure F.12: extend sign bit.
|
|
* On some machines, a shift and add will be faster than a table lookup.
|
|
*/
|
|
|
|
#ifdef AVOID_TABLES
|
|
|
|
#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
|
|
|
|
#else
|
|
|
|
#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
|
|
|
|
static const int extend_test[16] = /* entry n is 2**(n-1) */
|
|
{ 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
|
|
0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };
|
|
|
|
static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
|
|
{ 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,
|
|
((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,
|
|
((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,
|
|
((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };
|
|
|
|
#endif /* AVOID_TABLES */
|
|
|
|
|
|
/*
|
|
* Check for a restart marker & resynchronize decoder.
|
|
* Returns FALSE if must suspend.
|
|
*/
|
|
|
|
LOCAL(boolean)
|
|
process_restart (j_decompress_ptr cinfo)
|
|
{
|
|
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
|
|
int ci;
|
|
|
|
/* Throw away any unused bits remaining in bit buffer; */
|
|
/* include any full bytes in next_marker's count of discarded bytes */
|
|
cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;
|
|
entropy->bitstate.bits_left = 0;
|
|
|
|
/* Advance past the RSTn marker */
|
|
if (! (*cinfo->marker->read_restart_marker) (cinfo))
|
|
return FALSE;
|
|
|
|
/* Re-initialize DC predictions to 0 */
|
|
for (ci = 0; ci < cinfo->comps_in_scan; ci++)
|
|
entropy->saved.last_dc_val[ci] = 0;
|
|
|
|
/* Reset restart counter */
|
|
entropy->restarts_to_go = cinfo->restart_interval;
|
|
|
|
/* Next segment can get another out-of-data warning */
|
|
entropy->bitstate.printed_eod = FALSE;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
|
|
/*
|
|
* Decode and return one MCU's worth of Huffman-compressed coefficients.
|
|
* The coefficients are reordered from zigzag order into natural array order,
|
|
* but are not dequantized.
|
|
*
|
|
* The i'th block of the MCU is stored into the block pointed to by
|
|
* MCU_data[i]. WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER.
|
|
* (Wholesale zeroing is usually a little faster than retail...)
|
|
*
|
|
* Returns FALSE if data source requested suspension. In that case no
|
|
* changes have been made to permanent state. (Exception: some output
|
|
* coefficients may already have been assigned. This is harmless for
|
|
* this module, since we'll just re-assign them on the next call.)
|
|
*/
|
|
|
|
METHODDEF(boolean)
|
|
decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
|
|
{
|
|
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
|
|
register int s, k, r;
|
|
int blkn, ci;
|
|
JBLOCKROW block;
|
|
BITREAD_STATE_VARS;
|
|
savable_state state;
|
|
d_derived_tbl * dctbl;
|
|
d_derived_tbl * actbl;
|
|
jpeg_component_info * compptr;
|
|
|
|
/* Process restart marker if needed; may have to suspend */
|
|
if (cinfo->restart_interval) {
|
|
if (entropy->restarts_to_go == 0)
|
|
if (! process_restart(cinfo))
|
|
return FALSE;
|
|
}
|
|
|
|
/* Load up working state */
|
|
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
|
|
ASSIGN_STATE(state, entropy->saved);
|
|
|
|
/* Outer loop handles each block in the MCU */
|
|
|
|
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
|
|
block = MCU_data[blkn];
|
|
ci = cinfo->MCU_membership[blkn];
|
|
compptr = cinfo->cur_comp_info[ci];
|
|
dctbl = entropy->dc_derived_tbls[compptr->dc_tbl_no];
|
|
actbl = entropy->ac_derived_tbls[compptr->ac_tbl_no];
|
|
|
|
/* Decode a single block's worth of coefficients */
|
|
|
|
/* Section F.2.2.1: decode the DC coefficient difference */
|
|
HUFF_DECODE(s, br_state, dctbl, return FALSE, label1);
|
|
if (s) {
|
|
CHECK_BIT_BUFFER(br_state, s, return FALSE);
|
|
r = GET_BITS(s);
|
|
s = HUFF_EXTEND(r, s);
|
|
}
|
|
|
|
/* Shortcut if component's values are not interesting */
|
|
if (! compptr->component_needed)
|
|
goto skip_ACs;
|
|
|
|
/* Convert DC difference to actual value, update last_dc_val */
|
|
s += state.last_dc_val[ci];
|
|
state.last_dc_val[ci] = s;
|
|
/* Output the DC coefficient (assumes jpeg_natural_order[0] = 0) */
|
|
(*block)[0] = (JCOEF) s;
|
|
|
|
/* Do we need to decode the AC coefficients for this component? */
|
|
if (compptr->DCT_scaled_size > 1) {
|
|
|
|
/* Section F.2.2.2: decode the AC coefficients */
|
|
/* Since zeroes are skipped, output area must be cleared beforehand */
|
|
for (k = 1; k < DCTSIZE2; k++) {
|
|
HUFF_DECODE(s, br_state, actbl, return FALSE, label2);
|
|
|
|
r = s >> 4;
|
|
s &= 15;
|
|
|
|
if (s) {
|
|
k += r;
|
|
CHECK_BIT_BUFFER(br_state, s, return FALSE);
|
|
r = GET_BITS(s);
|
|
s = HUFF_EXTEND(r, s);
|
|
/* Output coefficient in natural (dezigzagged) order.
|
|
* Note: the extra entries in jpeg_natural_order[] will save us
|
|
* if k >= DCTSIZE2, which could happen if the data is corrupted.
|
|
*/
|
|
(*block)[jpeg_natural_order[k]] = (JCOEF) s;
|
|
} else {
|
|
if (r != 15)
|
|
break;
|
|
k += 15;
|
|
}
|
|
}
|
|
|
|
} else {
|
|
skip_ACs:
|
|
|
|
/* Section F.2.2.2: decode the AC coefficients */
|
|
/* In this path we just discard the values */
|
|
for (k = 1; k < DCTSIZE2; k++) {
|
|
HUFF_DECODE(s, br_state, actbl, return FALSE, label3);
|
|
|
|
r = s >> 4;
|
|
s &= 15;
|
|
|
|
if (s) {
|
|
k += r;
|
|
CHECK_BIT_BUFFER(br_state, s, return FALSE);
|
|
DROP_BITS(s);
|
|
} else {
|
|
if (r != 15)
|
|
break;
|
|
k += 15;
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
/* Completed MCU, so update state */
|
|
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
|
|
ASSIGN_STATE(entropy->saved, state);
|
|
|
|
/* Account for restart interval (no-op if not using restarts) */
|
|
entropy->restarts_to_go--;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
//MMX routines
|
|
|
|
//new Typedefs necessary for the new decode_mcu_fast to work.
|
|
typedef struct jpeg_source_mgr * j_csrc_ptr;
|
|
//typedef struct jpeg_err_mgr * j_cerr_ptr;
|
|
typedef struct jpeg_error_mgr * j_cerr_ptr;
|
|
|
|
typedef d_derived_tbl * h_pub_ptr;
|
|
/*
|
|
* Decode and return one MCU's worth of Huffman-compressed coefficients.
|
|
* The coefficients are reordered from zigzag order into natural array order,
|
|
* but are not dequantized.
|
|
*
|
|
* The i'th block of the MCU is stored into the block pointed to by
|
|
* MCU_data[i]. WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER.
|
|
* (Wholesale zeroing is usually a little faster than retail...)
|
|
*
|
|
* Returns FALSE if data source requested suspension. In that case no
|
|
* changes have been made to permanent state. (Exception: some output
|
|
* coefficients may already have been assigned. This is harmless for
|
|
* this module, since we'll just re-assign them on the next call.)
|
|
*/
|
|
|
|
const int twoexpnminusone[13] = { 0, 1, 2, 4, 8,16,32,64,128,256,512,1024,2048};
|
|
const int oneminustwoexpn[13] = { 0,-1,-3,-7,-15,-31,-63,-127,-255,-511,-1023,-2047};
|
|
|
|
|
|
//
|
|
// Need to add #ifdef for Alpha port
|
|
//
|
|
#if defined (_X86_)
|
|
|
|
METHODDEF(boolean)
|
|
decode_mcu_fast (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
|
|
{
|
|
// return decode_mcu_inner(cinfo,MCU_data);
|
|
//***************************************************************************/
|
|
//*
|
|
//* INTEL Corporation Proprietary Information
|
|
//*
|
|
//*
|
|
//* Copyright (c) 1996 Intel Corporation.
|
|
//* All rights reserved.
|
|
//*
|
|
//***************************************************************************/
|
|
// AUTHOR: Mark Buxton
|
|
/***************************************************************************/
|
|
// MMX version of the "Huffman Decoder" within the IJG decompressor code.
|
|
|
|
// // MMX Allocation:
|
|
//-------------------------------------------------------------
|
|
//// XXXX XXXX | XXXX XXXX
|
|
//
|
|
// MM0: ------------
|
|
// MM1: bit_buffer
|
|
// MM2: temp buffer
|
|
// MM3: temp buffer
|
|
// MM4: 0000 0000 0000 0040
|
|
// MM5: ------------ dctbl
|
|
// MM6: ------------ actbl
|
|
// MM7: ------------ temp_buffer
|
|
//
|
|
//
|
|
// edi - bits left in the Bit Buffer
|
|
|
|
// //routines to modify: jpeg_huff_decode_fast
|
|
// // fill_bit_buffer
|
|
//
|
|
//
|
|
//
|
|
// Other available storage locations:
|
|
//
|
|
// ebp - state
|
|
|
|
|
|
|
|
//data declaration:
|
|
|
|
unsigned char blkn;
|
|
unsigned char nbits;
|
|
JBLOCKROW block;
|
|
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
|
|
jpeg_component_info * compptr;
|
|
bitread_working_state br_state;
|
|
savable_state state;
|
|
d_derived_tbl * dctbl;
|
|
d_derived_tbl * actbl;
|
|
d_derived_tbl * htbl;
|
|
int ci,temp1;
|
|
int code;
|
|
int min_bits;
|
|
|
|
__asm {
|
|
// // Process restart marker if needed// may have to suspend
|
|
// if (cinfo->restart_interval) {
|
|
mov eax,dword ptr [cinfo]
|
|
cmp (j_decompress_ptr [eax]).restart_interval,1
|
|
jne Skip_Restart
|
|
//if (entropy->restarts_to_go == 0)
|
|
mov eax,dword ptr [entropy]
|
|
cmp (dword ptr [eax]).restarts_to_go,0
|
|
jne Skip_Restart
|
|
//if (! process_restart(cinfo))
|
|
mov eax,dword ptr [cinfo]
|
|
push eax
|
|
call process_restart
|
|
add esp,4
|
|
test eax,eax
|
|
jne Skip_Restart
|
|
|
|
jmp Return_Fail
|
|
|
|
Skip_Restart:
|
|
|
|
// // Load up working state
|
|
|
|
// br_state.cinfo = cinfop//
|
|
// br_state.next_input_byte = cinfop->src->next_input_byte//
|
|
// br_state.bytes_in_buffer = cinfop->src->bytes_in_buffer//
|
|
// br_state.unread_marker = cinfop->unread_marker//
|
|
// get_buffer = entropy->bitstate.get_buffer//
|
|
// bits_left = entropy->bitstate.bits_left//
|
|
// br_state.printed_eod_ptr = & entropy->bitstate.printed_eod
|
|
|
|
mov eax,dword ptr [cinfo]
|
|
mov dword ptr [br_state.cinfo],eax
|
|
|
|
|
|
mov ebx,(j_decompress_ptr [eax]).unread_marker
|
|
mov dword ptr [br_state.unread_marker],ebx
|
|
|
|
mov eax,(j_decompress_ptr [eax]).src
|
|
mov ebx,(j_csrc_ptr [eax]).next_input_byte
|
|
mov dword ptr [br_state.next_input_byte],ebx
|
|
|
|
mov ebx,(j_csrc_ptr [eax]).bytes_in_buffer
|
|
mov dword ptr [br_state.bytes_in_buffer],ebx
|
|
|
|
//pxor mm0,mm0
|
|
mov eax,dword ptr[entropy]
|
|
movq mm1,(qword ptr [eax]).bitstate.get_buffer_64
|
|
mov edi,(dword ptr [eax]).bitstate.bits_left
|
|
|
|
lea eax,dword ptr[eax].bitstate.printed_eod
|
|
mov dword ptr [br_state.printed_eod_ptr],eax
|
|
|
|
|
|
|
|
mov ebx,dword ptr [entropy]
|
|
xor eax,eax
|
|
mov eax,(dword ptr [ebx]).saved.last_dc_val[0x00]
|
|
mov dword ptr [state.last_dc_val+0x00],eax
|
|
mov eax,(dword ptr [ebx]).saved.last_dc_val[0x04]
|
|
mov dword ptr [state.last_dc_val+0x04],eax
|
|
mov eax,(dword ptr [ebx]).saved.last_dc_val[0x08]
|
|
mov dword ptr [state.last_dc_val+0x08],eax
|
|
mov eax,(dword ptr [ebx]).saved.last_dc_val[0x0C]
|
|
mov dword ptr [state.last_dc_val+0x0c],eax
|
|
|
|
//make sure all variables are initalized.
|
|
//see map in header for register usage
|
|
|
|
|
|
// // Outer loop handles each block in the MCU
|
|
|
|
//the address of each block is just MCU_data + blkn<<7 (this is MCU_data * 128, right?)
|
|
//ci = cinfo->MCU_membership[blkn];
|
|
//compptr = cinfo->cur_comp_info[ci];
|
|
//dctbl = entropy->dc_derived_tbls[compptr->dc_tbl_no];
|
|
//actbl = entropy->ac_derived_tbls[compptr->ac_tbl_no];
|
|
|
|
mov byte ptr [blkn],0
|
|
pxor mm5,mm5
|
|
pxor mm6,mm6
|
|
pxor mm2,mm2
|
|
pxor mm3,mm3
|
|
pxor mm4,mm4
|
|
mov eax,0x40
|
|
movd mm4,eax
|
|
|
|
|
|
}
|
|
One_Block_Loop:
|
|
block = MCU_data[blkn];
|
|
ci = cinfo->MCU_membership[blkn];
|
|
compptr = cinfo->cur_comp_info[ci];
|
|
actbl = entropy->ac_derived_tbls[compptr->ac_tbl_no];
|
|
dctbl = entropy->dc_derived_tbls[compptr->dc_tbl_no];
|
|
__asm
|
|
{
|
|
|
|
movd mm5,[dctbl]
|
|
movd mm6,[actbl]
|
|
//// Decode a single block's worth of coefficients
|
|
|
|
//// Section F.2.2.1: decode the DC coefficient difference
|
|
|
|
//---------------------------------------------------------------------------------
|
|
//DC loop section: there are probably only ~6 to process.
|
|
//---------------------------------------------------------------------------------
|
|
|
|
//set up the MMX registers:
|
|
//move the dctbl pointer into MM6
|
|
//pxor mm6,mm6
|
|
//movd mm6,dword ptr [dctbl]
|
|
//movd eax,mm0
|
|
|
|
|
|
cmp edi,8
|
|
jl Get_n_bits_DC
|
|
//normal path
|
|
//take a peek at the data in get_buffer.
|
|
Got_n_bits_DC:
|
|
movq mm3,mm1 //copy the Bit-Buffer
|
|
psrlq mm1,56 //Extract the MS 8 bits from the Bit Buffer
|
|
|
|
movd eax,mm5 //load the DC table pointer
|
|
movd ecx,mm1 //lsb holds the 8 input bits
|
|
|
|
movq mm1,mm3
|
|
mov ebx,(dword ptr[eax+4*ecx]).look_nbits
|
|
/*get the number of bits required to represent
|
|
this Huffman Code (n) . If the code is > 8 bits,
|
|
the table entry is Zero*/
|
|
|
|
test ebx,ebx
|
|
je Nineplus_Decode_DC//branch taken 3% of the time. If code > 8 bits,
|
|
//get it via a slower metho
|
|
|
|
movd mm2,ebx
|
|
sub edi,ebx //invalidate n bits from the Bit counter
|
|
|
|
xor ebx,ebx
|
|
psllq mm1,mm2 //invalidate n bits from the Bit Buffer
|
|
|
|
mov bl,(byte ptr[eax+ecx]).look_sym //read in the Run Lenth Code (rrrr|ssss); though for the DC coefct's rrrr=0000
|
|
|
|
Got_SymbolDC: //return point from the slow Huffman decoder routine (for code length > 8 bits)
|
|
cmp edi,ebx //
|
|
jl not_enough_bits_DC //If Not enough bits left in the Bit Buffer, Get More
|
|
|
|
Got_enough_bits_DC:
|
|
pxor mm2,mm2
|
|
sub edi,ebx //invalidate ssss bits from the Bit counter
|
|
|
|
movd mm2,ebx
|
|
movq mm3,mm4 //copy #64 into mm3
|
|
|
|
psubd mm3,mm2 //now mm3 has 64-ssss
|
|
movq mm0,mm1 //save a copy of the Bit Buffer
|
|
|
|
psrlq mm0,mm3 //shift result right
|
|
nop
|
|
|
|
psllq mm1,mm2 //Invalidate ssss bits from the Bit Buffer
|
|
movd ecx,mm0
|
|
|
|
|
|
mov eax,(dword ptr[twoexpnminusone+4*ebx]) //load 2^(ssss-1)
|
|
|
|
cmp ecx,eax //
|
|
jge positiv_symDC // If # < 2^(ssss-1), then # = #+(1-2^ssss)
|
|
|
|
add ecx,(dword ptr [oneminustwoexpn+4*ebx]) //
|
|
nop /****************************************/
|
|
positiv_symDC:
|
|
|
|
mov eax,dword ptr [compptr] //If !(compptr->compoent_needed), skip AC and DC coefts
|
|
mov edx,1 //initalize loop counter for AC coef't loop
|
|
|
|
cmp (dword ptr [eax]).component_needed,0
|
|
je skip_ACs
|
|
//don't skip the AC coefficients.
|
|
|
|
|
|
|
|
|
|
mov eax,[ci]
|
|
mov ebx,[block] //(*block)[0] = (JCOEF) s//
|
|
|
|
add ecx,(dword ptr[state.last_dc_val+eax*4]) //s += state.last_dc_val[ci]//
|
|
pxor mm7,mm7 //cleared for AC_coefficient calculations
|
|
|
|
mov (dword ptr[state.last_dc_val+eax*4]),ecx //state.last_dc_val[ci] = s//
|
|
|
|
mov word ptr[ebx],cx //store in (*block)
|
|
mov eax,[compptr]
|
|
|
|
cmp (dword ptr[eax]).DCT_scaled_size,1 //if (compptr->DCT_scaled_size > 1) {
|
|
jle skip_ACs
|
|
|
|
|
|
|
|
|
|
|
|
// Section F.2.2.2: decode the AC coefficients
|
|
// Since zeroes are skipped, output area must be cleared beforehand
|
|
//---------------------------------------------------------------------------------
|
|
//AC loop section: Active case.
|
|
//---------------------------------------------------------------------------------
|
|
Get_AC_DCT_loop:
|
|
|
|
|
|
cmp edi,8
|
|
jl Get_8_bits_ac
|
|
//take a peek at the data in get_buffer.
|
|
Full_8_bits_AC:
|
|
movq mm3,mm1 //copy Bit Buffer
|
|
psrlq mm1,56 //load msb from the Bit Buffer
|
|
|
|
movd ecx,mm6 //load AC Huffman Table Pointer
|
|
movd eax,mm1 //copy into integer reg. for address calculation
|
|
|
|
movq mm1,mm3
|
|
mov ebx,(dword ptr[ecx+4*eax]).look_nbits //If Huffman symbol is contained within 8 bits fetched,
|
|
//return the actual length of the sequence. If zero, len>8 bits
|
|
test ebx,ebx
|
|
je Nineplus_decode_AC
|
|
|
|
sub edi,ebx //invalidate n bits from Bit Counter
|
|
movd mm2,ebx
|
|
|
|
psllq mm1,mm2 //invalidate n bits from Bit Buffer
|
|
xor ebx,ebx
|
|
|
|
mov bl,(byte ptr[eax+ecx]).look_sym //load the Huffman Run Length code (rrrr|ssss) for this symbol
|
|
|
|
|
|
Got_SymbolAC: //return point from the slow Huffman routine
|
|
|
|
mov eax,ebx
|
|
|
|
shr eax,4 //highest nibble is run-length of zeroes (rrrr)
|
|
add edx,eax //increment AC coefft counter by the # of zeroes. Assume array is zeroed originally
|
|
|
|
and ebx,0x000F //isolate the lowest nibble, the bit-length of the actual coeff't (ssss)
|
|
jz Special_SymbolAC //a zero for the symbol bit-length indicates it is a special symbol. Ex: 0xF0, 0x00
|
|
|
|
//test to see if # available bits from bit_buffer are less than required to fill the Huffman symbol
|
|
//if insufficient bits, load new bit_buffer through fill_bit_buffer
|
|
|
|
cmp edi,ebx //ssss in ebx
|
|
jl Get_n_bits_ac
|
|
|
|
Got_n_bits_AC:
|
|
|
|
sub edi,ebx //invalidate ssss bits from the Bit counter
|
|
movd mm2,ebx
|
|
|
|
movq mm3,mm4 //copy #64 into mm3
|
|
psubd mm3,mm2 //now mm3 has 64-ssss
|
|
|
|
movq mm0,mm1 //save a copy of the Bit Buffer
|
|
psllq mm1,mm2 //Invalidate ssss bits from the Bit Buffer
|
|
|
|
psrlq mm0,mm3 //shift result right
|
|
mov eax,(dword ptr[twoexpnminusone+4*ebx]) //load 2^(ssss-1)
|
|
|
|
|
|
movd ecx,mm0
|
|
cmp ecx,eax //
|
|
//
|
|
jge positiv_symAC // If # < 2^(ssss-1), then # = #+(1-2^ssss)
|
|
add ecx,(dword ptr [oneminustwoexpn+4*ebx]) //
|
|
|
|
positiv_symAC:
|
|
//don't modify mm3. It has the actual AC-DCT coefficient.
|
|
|
|
// Output coefficient in natural (dezigzagged) order.
|
|
// Note: the extra entries in jpeg_natural_order[] will save us
|
|
// if the AC coefct index >= DCTSIZE2 (64), which could happen if the data is corrupted.
|
|
|
|
|
|
mov eax, dword ptr(jpeg_natural_order[4*edx]) //(*block)[jpeg_natural_order[k]]=s;
|
|
mov ebx, dword ptr [block]
|
|
|
|
mov word ptr([ebx+2*eax]),cx
|
|
ContinueAC:
|
|
inc edx //Ac coefct index ++
|
|
cmp edx,64 //While (index) < 64
|
|
jl Get_AC_DCT_loop //imples we are doing the loop 63 times (DC was the first, for 64 total COEFF"s)
|
|
|
|
Continue_Next_Block_AC:
|
|
inc byte ptr[blkn] //process the next Coeff. block
|
|
|
|
xor eax,eax
|
|
mov al,byte ptr[blkn]
|
|
|
|
mov edx,dword ptr[cinfo]
|
|
cmp eax,(j_decompress_ptr [edx]).blocks_in_MCU //While [blkn]<= Max number of blocks in MCU:
|
|
jge COMPLETED_MCU
|
|
jmp One_Block_Loop
|
|
|
|
/***************************************************************************************/
|
|
/* DC helper Code */
|
|
/***************************************************************************************/
|
|
|
|
Get_n_bits_DC: xor ebx,ebx//pass nbits in the eax register
|
|
call fill_bit_buffer
|
|
//if zero, it was probably suspended. Therefore suspend the whole DECODE_MCU
|
|
test eax,eax
|
|
je Return_Fail
|
|
cmp edi,8
|
|
jge Got_n_bits_DC //probable and predicted path is up.
|
|
mov ebx,1
|
|
jmp Slow_Decode_DC
|
|
|
|
not_enough_bits_DC:
|
|
call fill_bit_buffer
|
|
xor ebx,ebx
|
|
mov bl,byte ptr[nbits]
|
|
|
|
test eax,eax
|
|
jne Got_enough_bits_DC
|
|
jmp Return_Fail
|
|
|
|
Nineplus_Decode_DC:
|
|
mov ebx,9
|
|
Slow_Decode_DC: //aka slow_label. This is the _slow_ huff_decode.
|
|
|
|
mov eax,[dctbl]
|
|
mov [htbl],eax
|
|
call jpeg_huff_decode_fast //assume ebx holds nbits
|
|
test eax,eax
|
|
jl Return_Fail
|
|
mov ebx,eax
|
|
jmp Got_SymbolDC
|
|
|
|
/***************************************************************************************/
|
|
/* AC helper Code */
|
|
/***************************************************************************************/
|
|
|
|
Special_SymbolAC:
|
|
cmp al,0x0F
|
|
jne Continue_Next_Block_AC
|
|
jmp ContinueAC
|
|
|
|
Get_n_bits_ac:
|
|
call fill_bit_buffer
|
|
xor ebx,ebx
|
|
mov bl,byte ptr[nbits]
|
|
test eax,eax
|
|
jne Got_n_bits_AC
|
|
jmp Return_Fail
|
|
|
|
Get_8_bits_ac:
|
|
call fill_bit_buffer
|
|
test eax,eax
|
|
je Return_Fail
|
|
|
|
cmp edi,8
|
|
jge Full_8_bits_AC //probable and predicted path is up.
|
|
mov ebx,1
|
|
jmp Slow_decode_AC
|
|
|
|
Nineplus_decode_AC:
|
|
mov ebx,9
|
|
Slow_decode_AC: //The slow Huffman Decode. Used when the code length is > 8 bits
|
|
mov eax,[actbl]
|
|
mov [htbl],eax
|
|
call jpeg_huff_decode_fast //assume ebx holds nbits
|
|
test eax,eax
|
|
jl Return_Fail
|
|
mov ebx,eax
|
|
jmp Got_SymbolAC
|
|
|
|
|
|
//Failure, return from the routine
|
|
Return_Fail: //do not modify any permanent registers
|
|
emms
|
|
}
|
|
return FALSE;
|
|
__asm {
|
|
|
|
|
|
|
|
|
|
|
|
//} else {
|
|
|
|
//---------------------------------------------------------------------------------
|
|
//AC loop section: Ignore case.
|
|
//---------------------------------------------------------------------------------
|
|
skip_ACs:
|
|
|
|
// Section F.2.2.2: decode the AC coefficients
|
|
// In this path we just discard the values
|
|
|
|
Ignore_AC_DCT_loop:
|
|
|
|
cmp edi,8
|
|
jl Get_8_bits_acs
|
|
//take a peek at the data in get_buffer.
|
|
Full_8_bits_ACs:
|
|
movq mm3,mm1 //copy Bit Buffer
|
|
psrlq mm1,56 //load msb from the Bit Buffer
|
|
|
|
movd ecx,mm6 //load AC Huffman Table Pointer
|
|
movd eax,mm1 //copy into integer reg. for address calculation
|
|
|
|
movq mm1,mm3
|
|
mov ebx,(dword ptr[ecx+4*eax]).look_nbits //If Huffman symbol is contained within 8 bits fetched,
|
|
//return the actual length of the sequence. If zero, len>8 bits
|
|
test ebx,ebx
|
|
je Nineplus_Decode_ACs //If symbol > 8 bits, fetch the slow way. Called 3% of the time
|
|
|
|
sub edi,ebx //invalidate n bits from Bit Counter
|
|
movd mm2,ebx
|
|
|
|
|
|
psllq mm1,mm2 //invalidate n bits from Bit Buffer
|
|
xor ebx,ebx
|
|
|
|
mov bl,(byte ptr[eax+ecx]).look_sym //load the Huffman Run Length code (rrrr|ssss) for this symbol
|
|
|
|
Got_SymbolACs: //return point from the slow Huffman routine
|
|
|
|
mov eax,ebx
|
|
|
|
shr eax,4 //highest nibble is run-length of zeroes (rrrr)
|
|
add edx,eax //increment AC coefft counter by the # of zeroes. Assume array is zeroed originally
|
|
|
|
and ebx,0x000F //isolate the lowest nibble, the bit-length of the actual coeff't (ssss)
|
|
jz Special_SymbolACs //a zero for the symbol bit-length indicates it is a special symbol. Ex: 0xF0, 0x00
|
|
|
|
//test to see if # available bits from bit_buffer are less than required to fill the Huffman symbol
|
|
//if insufficient bits, load new bit_buffer through fill_bit_buffer
|
|
|
|
cmp edi,ebx //ssss in ebx
|
|
jl Get_n_bits_acs
|
|
|
|
Got_n_bits_acs:
|
|
|
|
sub edi,ebx //invalidate ssss bits from the Bit counter
|
|
movd mm2,ebx
|
|
psllq mm1,mm2 //Invalidate ssss bits from the Bit Buffer
|
|
|
|
Continue_ACs:
|
|
inc edx //Ac coefct index ++
|
|
cmp edx,64 //While (index) < 64
|
|
jl Ignore_AC_DCT_loop //imples we are doing the loop 63 times (DC was the first, for 64 total COEFF"s)
|
|
jmp Continue_Next_Block_AC
|
|
|
|
/***************************************************************************************/
|
|
/* Skipped AC helper Code */
|
|
/***************************************************************************************/
|
|
|
|
Special_SymbolACs:
|
|
cmp al,0x0F
|
|
jne Continue_Next_Block_AC
|
|
jmp Continue_ACs
|
|
|
|
Get_8_bits_acs:
|
|
call fill_bit_buffer
|
|
test eax,eax
|
|
je Return_Fail
|
|
|
|
cmp edi,8
|
|
jge Full_8_bits_ACs //probable and predicted path is up.
|
|
mov ebx,1
|
|
jmp Slow_Decode_ACs
|
|
Get_n_bits_acs:
|
|
call fill_bit_buffer
|
|
xor ebx,ebx
|
|
mov bl,byte ptr[nbits]
|
|
test eax,eax
|
|
jne Got_n_bits_acs
|
|
jmp Return_Fail
|
|
|
|
Nineplus_Decode_ACs:
|
|
mov ebx,9
|
|
Slow_Decode_ACs: //The slow Huffman Decode. Used when the code length is > 8 bits
|
|
mov eax,[actbl]
|
|
mov [htbl],eax
|
|
call jpeg_huff_decode_fast //assume ebx holds nbits
|
|
test eax,eax
|
|
jl Return_Fail
|
|
mov ebx,eax
|
|
jmp Got_SymbolACs
|
|
|
|
|
|
|
|
|
|
//} else {
|
|
|
|
|
|
COMPLETED_MCU:
|
|
|
|
// Completed MCU, so update state
|
|
|
|
//BITREAD_SAVE_STATE(cinfo,entropy->bitstate)//
|
|
//#define BITREAD_SAVE_STATE(cinfop,permstate)
|
|
|
|
// cinfo->src->next_input_byte = br_state.next_input_byte
|
|
// cinfo->src->bytes_in_buffer = br_state.bytes_in_buffer
|
|
// cinfo->unread_marker = br_state.unread_marker
|
|
// entropy->bitstate.get_buffer_64 = mm1
|
|
// entropy->bitstate.bits_left = mm0
|
|
|
|
mov eax,dword ptr [br_state.unread_marker]
|
|
mov ebx,dword ptr [cinfo]
|
|
mov (j_decompress_ptr [ebx]).unread_marker,eax
|
|
|
|
mov eax,dword ptr [br_state.next_input_byte]
|
|
mov ebx,(j_decompress_ptr [ebx]).src
|
|
mov (j_csrc_ptr [ebx]).next_input_byte,eax
|
|
|
|
mov eax,dword ptr [br_state.bytes_in_buffer]
|
|
mov (j_csrc_ptr [ebx]).bytes_in_buffer,eax
|
|
|
|
mov eax,dword ptr [entropy]
|
|
movq (qword ptr [eax]).bitstate.get_buffer_64,mm1
|
|
mov (dword ptr [eax]).bitstate.bits_left,edi
|
|
|
|
|
|
mov ebx,dword ptr [entropy]
|
|
mov eax,dword ptr [state.last_dc_val+0x00]
|
|
mov (dword ptr [ebx]).saved[0x00],eax
|
|
mov eax,dword ptr [state.last_dc_val+0x04]
|
|
mov (dword ptr [ebx]).saved[0x04],eax
|
|
mov eax,dword ptr [state.last_dc_val+0x08]
|
|
mov (dword ptr [ebx]).saved[0x08],eax
|
|
mov eax,dword ptr [state.last_dc_val+0x0C]
|
|
mov (dword ptr [ebx]).saved[0x0C],eax
|
|
|
|
|
|
// Account for restart interval (no-op if not using restarts)
|
|
emms
|
|
}
|
|
entropy->restarts_to_go--;
|
|
return TRUE;
|
|
|
|
//----------------------------------------------------------------------
|
|
|
|
|
|
/***************************************************************************
|
|
fill_bit_buffer:
|
|
Assembly procedure to decode Huffman coefficients longer than 8 bits.
|
|
Also called near the end of a data segment.
|
|
|
|
|
|
Input Parameters
|
|
al: minimum number of bits to get
|
|
|
|
various MMX registers and local variables must be defined; see
|
|
_decode_one_mcu_inner above
|
|
|
|
This code is called very frequently
|
|
****************************************************************************/
|
|
__asm {
|
|
fill_bit_buffer:
|
|
|
|
//use ecx to store bytes_in_buffer
|
|
//use ebx to store next_input_byte
|
|
//edi to store Bit Buffer length
|
|
|
|
//---------------------------------------------Main Looop----------
|
|
mov dword ptr [temp1],edx
|
|
mov byte ptr[nbits],bl //number of bits to get
|
|
//format the bit buffer: shift to the right by
|
|
//64-nbits
|
|
movd mm0,edi
|
|
movq mm7,mm4
|
|
|
|
|
|
mov ecx,dword ptr[br_state.bytes_in_buffer]
|
|
psubd mm7,mm0
|
|
|
|
|
|
psrlq mm1,mm7
|
|
mov ebx,dword ptr[br_state.next_input_byte]
|
|
|
|
|
|
//mov eax,8
|
|
//movd mm4,eax
|
|
// Attempt to read a byte */
|
|
cmp [br_state.unread_marker],0
|
|
jne no_more_data
|
|
|
|
test ecx,ecx
|
|
je call_load_more_bytes
|
|
|
|
//determine if there are enough bytes in the i/o buffer
|
|
|
|
continue_reading:
|
|
//decrement bytes_in_buffer//
|
|
dec ecx
|
|
js call_load_more_bytes
|
|
//load new data
|
|
|
|
xor eax,eax
|
|
mov al,byte ptr[ebx]
|
|
//update next_input_byte pointer
|
|
inc ebx
|
|
cmp eax,0xFF //compare ebx to FF
|
|
|
|
je got_FF
|
|
|
|
stuff_byte:
|
|
|
|
psllq mm1,8
|
|
movd mm7,eax
|
|
|
|
add edi,8
|
|
por mm1,mm7
|
|
|
|
//determine if we've read enough bytes
|
|
cmp edi,56
|
|
jle continue_reading
|
|
done_loading:
|
|
//were done loading data.
|
|
//stuff values for bytes_in_buffer, next_input_byte
|
|
mov [br_state.next_input_byte],ebx
|
|
mov [br_state.bytes_in_buffer],ecx
|
|
//finish formatting the bit_register
|
|
|
|
movd mm7,edi
|
|
movq mm0,mm4
|
|
|
|
psubd mm0,mm7
|
|
mov eax,0xFF
|
|
|
|
psllq mm1,mm0
|
|
mov edx, dword ptr [temp1]
|
|
|
|
ret
|
|
|
|
call_load_more_bytes:
|
|
call load_more_bytes
|
|
jmp continue_reading
|
|
//---------------------------------------End Main Loop-----------
|
|
|
|
got_FF:
|
|
//test to see if there are enough bytes in input_buffer
|
|
test ecx,ecx
|
|
jne continue_reading_2
|
|
call load_more_bytes
|
|
continue_reading_2:
|
|
//decrement bytes_in_buffer//
|
|
dec ecx
|
|
//load new data
|
|
xor eax,eax
|
|
mov al,[ebx]
|
|
//update next_input_byte pointer
|
|
inc ebx //do this twice?
|
|
cmp eax,0xff
|
|
je got_FF
|
|
test eax,eax
|
|
jne eod_marker
|
|
mov eax,0xFF
|
|
jmp stuff_byte //stuff an 'FF'
|
|
eod_marker: //byte was an end-of-data marker
|
|
mov [br_state.unread_marker],eax
|
|
//if we have enough bits in the input buffer to cover the required bits, ok.
|
|
//otherwise, warn the sytem about corrupt data.
|
|
|
|
no_more_data:
|
|
movd ebx,mm0
|
|
cmp bl,[nbits]
|
|
jl corrupt_data
|
|
//ok, have enough data,
|
|
jmp stuff_byte_corrupt
|
|
|
|
corrupt_data:
|
|
//this junk is the WARNMS macro
|
|
|
|
mov eax,dword ptr [br_state.printed_eod_ptr]
|
|
cmp dword ptr [eax],0x00
|
|
jne continue_corrupt
|
|
|
|
|
|
mov eax,dword ptr [cinfo]
|
|
mov eax,(j_decompress_ptr [eax]).err //the err struct is the first memer of state->cinfo
|
|
mov (j_cerr_ptr [eax]).msg_code,JWRN_HIT_MARKER
|
|
push 0xffffffff
|
|
|
|
mov eax,dword ptr [cinfo]
|
|
push eax
|
|
|
|
|
|
mov eax,dword ptr[cinfo] //the err struct is the first member of state->cinfo
|
|
mov eax,(j_decompress_ptr [eax]).err
|
|
call (j_cerr_ptr [eax]).emit_message
|
|
//call dword ptr[eax]
|
|
add esp,8
|
|
mov eax, dword ptr[br_state.printed_eod_ptr]
|
|
mov dword ptr [eax],1
|
|
continue_corrupt:
|
|
xor eax,eax
|
|
jmp stuff_byte_corrupt
|
|
|
|
stuff_byte_corrupt:
|
|
psllq mm1,8
|
|
movd mm7,eax
|
|
add edi,8
|
|
por mm1,mm7
|
|
|
|
//determine if we've read enough bytes
|
|
cmp edi,56
|
|
jle stuff_byte_corrupt
|
|
jmp done_loading
|
|
|
|
|
|
|
|
load_more_bytes:
|
|
movd mm0,edi
|
|
mov [br_state.next_input_byte],ebx
|
|
mov eax,[br_state.cinfo]
|
|
push eax
|
|
mov eax,[br_state.cinfo]
|
|
mov eax,(j_decompress_ptr[eax]).src
|
|
movd mm0,edi
|
|
call (j_csrc_ptr [eax]).fill_input_buffer
|
|
add esp,4
|
|
//eax has the return value. If zero, bomb out
|
|
test eax,eax
|
|
je return_4
|
|
//update next_input_byte and bytes_in_buffer.
|
|
mov eax,[br_state.cinfo]
|
|
mov eax,(j_decompress_ptr[eax]).src
|
|
mov ebx,(j_csrc_ptr [eax]).next_input_byte;
|
|
mov ecx,(j_csrc_ptr [eax]).bytes_in_buffer;
|
|
movd edi,mm0
|
|
mov edx,dword ptr[temp1]
|
|
ret
|
|
|
|
|
|
return_4:
|
|
mov eax,0x40
|
|
movd mm4,eax
|
|
mov eax,0
|
|
mov edx,[temp1]
|
|
emms
|
|
ret
|
|
|
|
|
|
//End fill_bit_buffer--------------------------------------------------
|
|
//--------------------------------------------------------------------------
|
|
//--------------------------------------------------------------------------
|
|
|
|
/***************************************************************************
|
|
Jpeg_huff_decode_fast.
|
|
Assembly procedure to decode Huffman coefficients longer than 8 bits.
|
|
Also called near the end of a data segment.
|
|
|
|
|
|
Input Parameters
|
|
eax: minimum number of bits for the next huffman code.
|
|
|
|
various MMX registers and local variables must be defined; see
|
|
_decode_one_mcu_inner above
|
|
|
|
This code is infrequently called
|
|
****************************************************************************/
|
|
|
|
jpeg_huff_decode_fast:
|
|
/* HUFF_DECODE has determined that the code is at least min_bits */
|
|
/* bits long, so fetch that many bits in one swoop. */
|
|
push edx
|
|
mov [min_bits],ebx
|
|
|
|
cmp edi,ebx
|
|
jl Fill_Input_Buffer
|
|
Filled_Up:
|
|
|
|
sub edi,ebx
|
|
movq mm3,mm4
|
|
|
|
movd mm7,ebx
|
|
movq mm2,mm1
|
|
|
|
psubd mm3,mm7
|
|
psllq mm1,mm7
|
|
|
|
psrlq mm2,mm3
|
|
movd ecx,mm2
|
|
|
|
Continue_Tedious_1:
|
|
//now mm7 holds the most recent code
|
|
|
|
/* Collect the rest of the Huffman code one bit at a time. */
|
|
/* This is per Figure F.16 in the JPEG spec. */
|
|
mov eax,dword ptr [min_bits]
|
|
mov edx,dword ptr [htbl]
|
|
//mov ecx,dword ptr [code]
|
|
mov ebx,dword ptr [edx+eax*4].maxcode
|
|
cmp ebx,ecx
|
|
jge Continue_Tedious_2b
|
|
|
|
//while (code > htbl->maxcode[min_bits]) {
|
|
|
|
//movd eax,mm0
|
|
cmp edi,1
|
|
jl Fill_Input_Buffer_2
|
|
Filled_Up_2:
|
|
|
|
dec edi
|
|
movq mm3,mm1
|
|
|
|
psrlq mm3,63
|
|
|
|
movd mm7,ecx
|
|
psllq mm1,1
|
|
|
|
psllq mm7,1
|
|
inc [min_bits]
|
|
|
|
por mm7,mm3
|
|
movd ecx,mm7
|
|
|
|
jmp Continue_Tedious_1
|
|
|
|
Fill_Input_Buffer:
|
|
//al should hold the number of valid bits;
|
|
//mov eax,ebx
|
|
call fill_bit_buffer
|
|
//if it returned a zero, exit with a -1.
|
|
test eax,eax
|
|
je Suspend_Label
|
|
//we were able to fill it with (some) data.
|
|
//jump back to the continuation of this loop:
|
|
xor ebx,ebx
|
|
mov ebx,[min_bits]
|
|
jmp Filled_Up
|
|
|
|
|
|
|
|
Fill_Input_Buffer_2:
|
|
|
|
mov ebx,1
|
|
mov [code],ecx
|
|
call fill_bit_buffer
|
|
//if it returned a zero, exit with a -1.
|
|
test eax,eax
|
|
je Suspend_Label
|
|
//we were able to fill it with (some) data.
|
|
//jump back to the continuation of this loop:
|
|
mov ecx,[code]
|
|
jmp Filled_Up_2
|
|
|
|
Continue_Tedious_2b:
|
|
push edi
|
|
/* With garbage input we may reach the sentinel value l = 17. */
|
|
}
|
|
if (min_bits > 16) {
|
|
WARNMS(br_state.cinfo, JWRN_HUFF_BAD_CODE);
|
|
__asm {
|
|
pop edi
|
|
xor eax,eax
|
|
pop edx
|
|
ret
|
|
}
|
|
}
|
|
|
|
/*code= htbl->pub->huffval[ htbl->valptr[min_bits] +
|
|
((int) (code - htbl->mincode[min_bits])) ];*/
|
|
__asm{
|
|
pop edi
|
|
mov eax,dword ptr [min_bits]
|
|
mov ebx,dword ptr [htbl]
|
|
sub ecx,(dword ptr [ebx+eax*4]).mincode
|
|
add ecx,(dword ptr [ebx+eax*4]).valptr
|
|
mov ebx,(h_pub_ptr [ebx]).pub
|
|
xor eax,eax
|
|
mov al,(byte ptr [ecx+ebx]).huffval
|
|
pop edx
|
|
ret
|
|
|
|
Suspend_Label:
|
|
|
|
mov eax,1
|
|
pop edx
|
|
ret
|
|
}
|
|
}
|
|
//End jpeg_huff_decode_fast-------------------------------------------------
|
|
//--------------------------------------------------------------------------
|
|
//--------------------------------------------------------------------------
|
|
|
|
#endif // defined (_X86_)
|
|
|
|
|
|
/*
|
|
* Module initialization routine for Huffman entropy decoding.
|
|
*/
|
|
|
|
GLOBAL(void)
|
|
jinit_huff_decoder (j_decompress_ptr cinfo)
|
|
{
|
|
huff_entropy_ptr entropy;
|
|
int i;
|
|
|
|
entropy = (huff_entropy_ptr)
|
|
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
|
SIZEOF(huff_entropy_decoder));
|
|
cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;
|
|
entropy->pub.start_pass = start_pass_huff_decoder;
|
|
//
|
|
// Need to add #ifdef for Alpha port
|
|
//
|
|
#if defined (_X86_)
|
|
if (vfMMXMachine)
|
|
{
|
|
entropy->pub.decode_mcu = decode_mcu_fast;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
entropy->pub.decode_mcu = decode_mcu;
|
|
}
|
|
|
|
/* Mark tables unallocated */
|
|
for (i = 0; i < NUM_HUFF_TBLS; i++) {
|
|
entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;
|
|
}
|
|
}
|