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windows-nt/Source/XPSP1/NT/shell/shell32/tngen/jdhuff.cpp

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#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;
}
}
Reference in a new issue Copy permalink