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- /*
- * 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 */
- /*
- * 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)
- __cdecl 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};
- #ifdef _X86_
- METHODDEF(boolean)
- __cdecl 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:
- xor eax, eax
- //movd ebx,mm0 //dshade
- //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,dword ptr[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
- }
- }
- #endif
- //End jpeg_huff_decode_fast-------------------------------------------------
- //--------------------------------------------------------------------------
- //--------------------------------------------------------------------------
- /*
- * 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;
- #if 0
- //#ifdef _X86_
- if (vfMMXMachine)
- {
- entropy->pub.decode_mcu = decode_mcu_fast;
- }
- else
- {
- entropy->pub.decode_mcu = decode_mcu;
- }
- #else
- entropy->pub.decode_mcu = decode_mcu;
- #endif
- /* Mark tables unallocated */
- for (i = 0; i < NUM_HUFF_TBLS; i++) {
- entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;
- }
- }
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