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1574 lines
44 KiB
1574 lines
44 KiB
#include "stdafx.h"
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#pragma hdrstop
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/*
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* jdhuff.c
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*
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* Copyright (C) 1991-1996, Thomas G. Lane.
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* This file is part of the Independent JPEG Group's software.
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* For conditions of distribution and use, see the accompanying README file.
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*
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* This file contains Huffman entropy decoding routines.
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*
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* Much of the complexity here has to do with supporting input suspension.
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* If the data source module demands suspension, we want to be able to back
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* up to the start of the current MCU. To do this, we copy state variables
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* into local working storage, and update them back to the permanent
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* storage only upon successful completion of an MCU.
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*/
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#define JPEG_INTERNALS
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#include "jinclude.h"
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#include "jpeglib.h"
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#include "jdhuff.h" /* Declarations shared with jdphuff.c */
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#ifdef _M_IX86
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#pragma warning(disable:4799)
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#endif
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/*
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* Expanded entropy decoder object for Huffman decoding.
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*
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* The savable_state subrecord contains fields that change within an MCU,
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* but must not be updated permanently until we complete the MCU.
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*/
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typedef struct {
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int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
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} savable_state;
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/* This macro is to work around compilers with missing or broken
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* structure assignment. You'll need to fix this code if you have
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* such a compiler and you change MAX_COMPS_IN_SCAN.
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*/
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#ifndef NO_STRUCT_ASSIGN
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#define ASSIGN_STATE(dest,src) ((dest) = (src))
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#else
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#if MAX_COMPS_IN_SCAN == 4
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#define ASSIGN_STATE(dest,src) \
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((dest).last_dc_val[0] = (src).last_dc_val[0], \
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(dest).last_dc_val[1] = (src).last_dc_val[1], \
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(dest).last_dc_val[2] = (src).last_dc_val[2], \
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(dest).last_dc_val[3] = (src).last_dc_val[3])
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#endif
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#endif
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typedef struct {
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struct jpeg_entropy_decoder pub; /* public fields */
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/* These fields are loaded into local variables at start of each MCU.
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* In case of suspension, we exit WITHOUT updating them.
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*/
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bitread_perm_state bitstate; /* Bit buffer at start of MCU */
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savable_state saved; /* Other state at start of MCU */
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/* These fields are NOT loaded into local working state. */
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unsigned int restarts_to_go; /* MCUs left in this restart interval */
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/* Pointers to derived tables (these workspaces have image lifespan) */
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d_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];
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d_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];
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} huff_entropy_decoder;
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typedef huff_entropy_decoder * huff_entropy_ptr;
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/*
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* Initialize for a Huffman-compressed scan.
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*/
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METHODDEF(void)
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start_pass_huff_decoder (j_decompress_ptr cinfo)
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{
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huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
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int ci, dctbl, actbl;
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jpeg_component_info * compptr;
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/* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG.
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* This ought to be an error condition, but we make it a warning because
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* there are some baseline files out there with all zeroes in these bytes.
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*/
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if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 ||
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cinfo->Ah != 0 || cinfo->Al != 0)
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WARNMS(cinfo, JWRN_NOT_SEQUENTIAL);
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for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
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compptr = cinfo->cur_comp_info[ci];
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dctbl = compptr->dc_tbl_no;
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actbl = compptr->ac_tbl_no;
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/* Make sure requested tables are present */
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if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS ||
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cinfo->dc_huff_tbl_ptrs[dctbl] == NULL)
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ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);
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if (actbl < 0 || actbl >= NUM_HUFF_TBLS ||
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cinfo->ac_huff_tbl_ptrs[actbl] == NULL)
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ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl);
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/* Compute derived values for Huffman tables */
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/* We may do this more than once for a table, but it's not expensive */
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jpeg_make_d_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[dctbl],
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& entropy->dc_derived_tbls[dctbl]);
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jpeg_make_d_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[actbl],
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& entropy->ac_derived_tbls[actbl]);
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/* Initialize DC predictions to 0 */
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entropy->saved.last_dc_val[ci] = 0;
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}
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/* Initialize bitread state variables */
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entropy->bitstate.bits_left = 0;
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entropy->bitstate.get_buffer_64 = 0;
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entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
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entropy->bitstate.printed_eod = FALSE;
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/* Initialize restart counter */
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entropy->restarts_to_go = cinfo->restart_interval;
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}
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/*
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* Compute the derived values for a Huffman table.
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* Note this is also used by jdphuff.c.
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*/
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GLOBAL(void)
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jpeg_make_d_derived_tbl (j_decompress_ptr cinfo, JHUFF_TBL * htbl,
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d_derived_tbl ** pdtbl)
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{
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d_derived_tbl *dtbl;
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int p, i, l, si;
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int lookbits, ctr;
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char huffsize[257];
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unsigned int huffcode[257];
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unsigned int code;
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/* Allocate a workspace if we haven't already done so. */
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if (*pdtbl == NULL)
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*pdtbl = (d_derived_tbl *)
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(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
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SIZEOF(d_derived_tbl));
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dtbl = *pdtbl;
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dtbl->pub = htbl; /* fill in back link */
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/* Figure C.1: make table of Huffman code length for each symbol */
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/* Note that this is in code-length order. */
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p = 0;
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for (l = 1; l <= 16; l++) {
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for (i = 1; i <= (int) htbl->bits[l]; i++)
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huffsize[p++] = (char) l;
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}
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huffsize[p] = 0;
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/* Figure C.2: generate the codes themselves */
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/* Note that this is in code-length order. */
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code = 0;
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si = huffsize[0];
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p = 0;
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while (huffsize[p]) {
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while (((int) huffsize[p]) == si) {
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huffcode[p++] = code;
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code++;
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}
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code <<= 1;
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si++;
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}
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/* Figure F.15: generate decoding tables for bit-sequential decoding */
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p = 0;
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for (l = 1; l <= 16; l++) {
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if (htbl->bits[l]) {
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dtbl->valptr[l] = p; /* huffval[] index of 1st symbol of code length l */
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dtbl->mincode[l] = huffcode[p]; /* minimum code of length l */
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p += htbl->bits[l];
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dtbl->maxcode[l] = huffcode[p-1]; /* maximum code of length l */
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} else {
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dtbl->maxcode[l] = -1; /* -1 if no codes of this length */
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}
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}
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dtbl->maxcode[17] = 0xFFFFFL; /* ensures jpeg_huff_decode terminates */
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/* Compute lookahead tables to speed up decoding.
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* First we set all the table entries to 0, indicating "too long";
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* then we iterate through the Huffman codes that are short enough and
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* fill in all the entries that correspond to bit sequences starting
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* with that code.
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*/
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MEMZERO(dtbl->look_nbits, SIZEOF(dtbl->look_nbits));
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p = 0;
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for (l = 1; l <= HUFF_LOOKAHEAD; l++) {
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for (i = 1; i <= (int) htbl->bits[l]; i++, p++) {
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/* l = current code's length, p = its index in huffcode[] & huffval[]. */
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/* Generate left-justified code followed by all possible bit sequences */
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lookbits = huffcode[p] << (HUFF_LOOKAHEAD-l);
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for (ctr = 1 << (HUFF_LOOKAHEAD-l); ctr > 0; ctr--) {
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dtbl->look_nbits[lookbits] = l;
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dtbl->look_sym[lookbits] = htbl->huffval[p];
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lookbits++;
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}
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}
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}
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}
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/*
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* Out-of-line code for bit fetching (shared with jdphuff.c).
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* See jdhuff.h for info about usage.
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* Note: current values of get_buffer and bits_left are passed as parameters,
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* but are returned in the corresponding fields of the state struct.
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*
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* On most machines MIN_GET_BITS should be 25 to allow the full 32-bit width
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* of get_buffer to be used. (On machines with wider words, an even larger
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* buffer could be used.) However, on some machines 32-bit shifts are
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* quite slow and take time proportional to the number of places shifted.
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* (This is true with most PC compilers, for instance.) In this case it may
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* be a win to set MIN_GET_BITS to the minimum value of 15. This reduces the
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* average shift distance at the cost of more calls to jpeg_fill_bit_buffer.
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*/
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#ifdef SLOW_SHIFT_32
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#define MIN_GET_BITS 15 /* minimum allowable value */
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#else
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#define MIN_GET_BITS (BIT_BUF_SIZE-7)
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#endif
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// not used in MMX version
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GLOBAL(boolean)
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jpeg_fill_bit_buffer (bitread_working_state * state,
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register bit_buf_type get_buffer, register int bits_left,
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int nbits)
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/* Load up the bit buffer to a depth of at least nbits */
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{
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/* Copy heavily used state fields into locals (hopefully registers) */
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register const JOCTET * next_input_byte = state->next_input_byte;
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register size_t bytes_in_buffer = state->bytes_in_buffer;
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register int c;
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/* Attempt to load at least MIN_GET_BITS bits into get_buffer. */
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/* (It is assumed that no request will be for more than that many bits.) */
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while (bits_left < MIN_GET_BITS) {
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/* Attempt to read a byte */
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if (state->unread_marker != 0)
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goto no_more_data; /* can't advance past a marker */
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if (bytes_in_buffer == 0) {
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if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))
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return FALSE;
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next_input_byte = state->cinfo->src->next_input_byte;
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bytes_in_buffer = state->cinfo->src->bytes_in_buffer;
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}
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bytes_in_buffer--;
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c = GETJOCTET(*next_input_byte++);
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/* If it's 0xFF, check and discard stuffed zero byte */
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if (c == 0xFF) {
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do {
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if (bytes_in_buffer == 0) {
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if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))
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return FALSE;
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next_input_byte = state->cinfo->src->next_input_byte;
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bytes_in_buffer = state->cinfo->src->bytes_in_buffer;
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}
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bytes_in_buffer--;
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c = GETJOCTET(*next_input_byte++);
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} while (c == 0xFF);
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if (c == 0) {
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/* Found FF/00, which represents an FF data byte */
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c = 0xFF;
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} else {
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/* Oops, it's actually a marker indicating end of compressed data. */
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/* Better put it back for use later */
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state->unread_marker = c;
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no_more_data:
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/* There should be enough bits still left in the data segment; */
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/* if so, just break out of the outer while loop. */
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if (bits_left >= nbits)
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break;
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/* Uh-oh. Report corrupted data to user and stuff zeroes into
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* the data stream, so that we can produce some kind of image.
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* Note that this code will be repeated for each byte demanded
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* for the rest of the segment. We use a nonvolatile flag to ensure
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* that only one warning message appears.
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*/
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if (! *(state->printed_eod_ptr)) {
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WARNMS(state->cinfo, JWRN_HIT_MARKER);
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*(state->printed_eod_ptr) = TRUE;
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}
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c = 0; /* insert a zero byte into bit buffer */
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}
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}
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/* OK, load c into get_buffer */
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get_buffer = (get_buffer << 8) | c;
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bits_left += 8;
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}
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/* Unload the local registers */
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state->next_input_byte = next_input_byte;
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state->bytes_in_buffer = bytes_in_buffer;
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state->get_buffer = get_buffer;
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state->bits_left = bits_left;
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return TRUE;
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}
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/*
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* Out-of-line code for Huffman code decoding.
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* See jdhuff.h for info about usage.
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*/
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GLOBAL(int)
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jpeg_huff_decode (bitread_working_state * state,
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register bit_buf_type get_buffer, register int bits_left,
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d_derived_tbl * htbl, int min_bits)
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{
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register int l = min_bits;
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register INT32 code;
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/* HUFF_DECODE has determined that the code is at least min_bits */
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/* bits long, so fetch that many bits in one swoop. */
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CHECK_BIT_BUFFER(*state, l, return -1);
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code = GET_BITS(l);
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/* Collect the rest of the Huffman code one bit at a time. */
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/* This is per Figure F.16 in the JPEG spec. */
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while (code > htbl->maxcode[l]) {
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code <<= 1;
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CHECK_BIT_BUFFER(*state, 1, return -1);
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code |= GET_BITS(1);
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l++;
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}
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/* Unload the local registers */
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state->get_buffer = get_buffer;
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state->bits_left = bits_left;
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/* With garbage input we may reach the sentinel value l = 17. */
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if (l > 16) {
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WARNMS(state->cinfo, JWRN_HUFF_BAD_CODE);
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return 0; /* fake a zero as the safest result */
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}
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return htbl->pub->huffval[ htbl->valptr[l] +
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((int) (code - htbl->mincode[l])) ];
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}
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/*
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* Figure F.12: extend sign bit.
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* On some machines, a shift and add will be faster than a table lookup.
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*/
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#ifdef AVOID_TABLES
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#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
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#else
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#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
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static const int extend_test[16] = /* entry n is 2**(n-1) */
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{ 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
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0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };
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static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
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{ 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,
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((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,
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((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,
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((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };
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#endif /* AVOID_TABLES */
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/*
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* Check for a restart marker & resynchronize decoder.
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* Returns FALSE if must suspend.
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*/
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LOCAL(boolean)
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process_restart (j_decompress_ptr cinfo)
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{
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huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
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int ci;
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/* Throw away any unused bits remaining in bit buffer; */
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/* include any full bytes in next_marker's count of discarded bytes */
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cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;
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entropy->bitstate.bits_left = 0;
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/* Advance past the RSTn marker */
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if (! (*cinfo->marker->read_restart_marker) (cinfo))
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return FALSE;
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/* Re-initialize DC predictions to 0 */
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for (ci = 0; ci < cinfo->comps_in_scan; ci++)
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entropy->saved.last_dc_val[ci] = 0;
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/* Reset restart counter */
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entropy->restarts_to_go = cinfo->restart_interval;
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/* Next segment can get another out-of-data warning */
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entropy->bitstate.printed_eod = FALSE;
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return TRUE;
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}
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|
|
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/*
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* Decode and return one MCU's worth of Huffman-compressed coefficients.
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* The coefficients are reordered from zigzag order into natural array order,
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* but are not dequantized.
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*
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* The i'th block of the MCU is stored into the block pointed to by
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* MCU_data[i]. WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER.
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* (Wholesale zeroing is usually a little faster than retail...)
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*
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* Returns FALSE if data source requested suspension. In that case no
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* changes have been made to permanent state. (Exception: some output
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* coefficients may already have been assigned. This is harmless for
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* this module, since we'll just re-assign them on the next call.)
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*/
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METHODDEF(boolean)
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decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
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{
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huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
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register int s, k, r;
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int blkn, ci;
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JBLOCKROW block;
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BITREAD_STATE_VARS;
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savable_state state;
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d_derived_tbl * dctbl;
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d_derived_tbl * actbl;
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jpeg_component_info * compptr;
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/* Process restart marker if needed; may have to suspend */
|
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if (cinfo->restart_interval) {
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if (entropy->restarts_to_go == 0)
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if (! process_restart(cinfo))
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return FALSE;
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}
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/* Load up working state */
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BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
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ASSIGN_STATE(state, entropy->saved);
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|
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/* Outer loop handles each block in the MCU */
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for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
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block = MCU_data[blkn];
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ci = cinfo->MCU_membership[blkn];
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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)
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jinit_huff_decoder (j_decompress_ptr cinfo)
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{
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huff_entropy_ptr entropy;
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int i;
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entropy = (huff_entropy_ptr)
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(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
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SIZEOF(huff_entropy_decoder));
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cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;
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entropy->pub.start_pass = start_pass_huff_decoder;
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//
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// Need to add #ifdef for Alpha port
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//
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#if defined (_X86_)
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if (vfMMXMachine)
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{
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entropy->pub.decode_mcu = decode_mcu_fast;
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}
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else
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#endif
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{
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entropy->pub.decode_mcu = decode_mcu;
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}
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/* Mark tables unallocated */
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for (i = 0; i < NUM_HUFF_TBLS; i++) {
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entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;
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}
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}
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