/*
* jdphuff.c
*
+ * This file was part of the Independent JPEG Group's software:
* Copyright (C) 1995-1997, 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.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 2015-2016, 2018, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
*
* This file contains Huffman entropy decoding routines for progressive JPEG.
*
* 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.
+ *
+ * NOTE: All referenced figures are from
+ * Recommendation ITU-T T.81 (1992) | ISO/IEC 10918-1:1994.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
-#include "jdhuff.h" /* Declarations shared with jdhuff.c */
+#include "jdhuff.h" /* Declarations shared with jdhuff.c */
+#include <limits.h>
#ifdef D_PROGRESSIVE_SUPPORTED
*/
typedef struct {
- unsigned int EOBRUN; /* remaining EOBs in EOBRUN */
- int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
+ unsigned int EOBRUN; /* remaining EOBs in EOBRUN */
+ 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
*/
#ifndef NO_STRUCT_ASSIGN
-#define ASSIGN_STATE(dest,src) ((dest) = (src))
+#define ASSIGN_STATE(dest, src) ((dest) = (src))
#else
#if MAX_COMPS_IN_SCAN == 4
-#define ASSIGN_STATE(dest,src) \
- ((dest).EOBRUN = (src).EOBRUN, \
- (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])
+#define ASSIGN_STATE(dest, src) \
+ ((dest).EOBRUN = (src).EOBRUN, \
+ (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
/* 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 */
+ 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 */
+ unsigned int restarts_to_go; /* MCUs left in this restart interval */
/* Pointers to derived tables (these workspaces have image lifespan) */
- d_derived_tbl * derived_tbls[NUM_HUFF_TBLS];
+ d_derived_tbl *derived_tbls[NUM_HUFF_TBLS];
- d_derived_tbl * ac_derived_tbl; /* active table during an AC scan */
+ d_derived_tbl *ac_derived_tbl; /* active table during an AC scan */
} phuff_entropy_decoder;
-typedef phuff_entropy_decoder * phuff_entropy_ptr;
+typedef phuff_entropy_decoder *phuff_entropy_ptr;
/* Forward declarations */
-METHODDEF(boolean) decode_mcu_DC_first JPP((j_decompress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) decode_mcu_AC_first JPP((j_decompress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) decode_mcu_DC_refine JPP((j_decompress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) decode_mcu_AC_refine JPP((j_decompress_ptr cinfo,
- JBLOCKROW *MCU_data));
+METHODDEF(boolean) decode_mcu_DC_first(j_decompress_ptr cinfo,
+ JBLOCKROW *MCU_data);
+METHODDEF(boolean) decode_mcu_AC_first(j_decompress_ptr cinfo,
+ JBLOCKROW *MCU_data);
+METHODDEF(boolean) decode_mcu_DC_refine(j_decompress_ptr cinfo,
+ JBLOCKROW *MCU_data);
+METHODDEF(boolean) decode_mcu_AC_refine(j_decompress_ptr cinfo,
+ JBLOCKROW *MCU_data);
/*
*/
METHODDEF(void)
-start_pass_phuff_decoder (j_decompress_ptr cinfo)
+start_pass_phuff_decoder(j_decompress_ptr cinfo)
{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
boolean is_DC_band, bad;
int ci, coefi, tbl;
+ d_derived_tbl **pdtbl;
int *coef_bit_ptr;
- jpeg_component_info * compptr;
+ jpeg_component_info *compptr;
is_DC_band = (cinfo->Ss == 0);
}
if (cinfo->Ah != 0) {
/* Successive approximation refinement scan: must have Al = Ah-1. */
- if (cinfo->Al != cinfo->Ah-1)
+ if (cinfo->Al != cinfo->Ah - 1)
bad = TRUE;
}
- if (cinfo->Al > 13) /* need not check for < 0 */
+ if (cinfo->Al > 13) /* need not check for < 0 */
bad = TRUE;
/* Arguably the maximum Al value should be less than 13 for 8-bit precision,
* but the spec doesn't say so, and we try to be liberal about what we
*/
if (bad)
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
- cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
+ cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
/* Update progression status, and verify that scan order is legal.
* Note that inter-scan inconsistencies are treated as warnings
* not fatal errors ... not clear if this is right way to behave.
*/
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
int cindex = cinfo->cur_comp_info[ci]->component_index;
- coef_bit_ptr = & cinfo->coef_bits[cindex][0];
+ coef_bit_ptr = &cinfo->coef_bits[cindex][0];
if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0);
for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) {
int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi];
if (cinfo->Ah != expected)
- WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);
+ WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);
coef_bit_ptr[coefi] = cinfo->Al;
}
}
* We may build same derived table more than once, but it's not expensive.
*/
if (is_DC_band) {
- if (cinfo->Ah == 0) { /* DC refinement needs no table */
- tbl = compptr->dc_tbl_no;
- jpeg_make_d_derived_tbl(cinfo, TRUE, tbl,
- & entropy->derived_tbls[tbl]);
+ if (cinfo->Ah == 0) { /* DC refinement needs no table */
+ tbl = compptr->dc_tbl_no;
+ pdtbl = (d_derived_tbl **)(entropy->derived_tbls) + tbl;
+ jpeg_make_d_derived_tbl(cinfo, TRUE, tbl, pdtbl);
}
} else {
tbl = compptr->ac_tbl_no;
- jpeg_make_d_derived_tbl(cinfo, FALSE, tbl,
- & entropy->derived_tbls[tbl]);
+ pdtbl = (d_derived_tbl **)(entropy->derived_tbls) + tbl;
+ jpeg_make_d_derived_tbl(cinfo, FALSE, tbl, pdtbl);
/* remember the single active table */
entropy->ac_derived_tbl = entropy->derived_tbls[tbl];
}
#define AVOID_TABLES
#ifdef AVOID_TABLES
-#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
+#define NEG_1 ((unsigned)-1)
+#define HUFF_EXTEND(x, s) \
+ ((x) < (1 << ((s) - 1)) ? (x) + (((NEG_1) << (s)) + 1) : (x))
#else
-#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
+#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_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 };
+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 */
*/
LOCAL(boolean)
-process_restart (j_decompress_ptr cinfo)
+process_restart(j_decompress_ptr cinfo)
{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
int ci;
/* Throw away any unused bits remaining in bit buffer; */
entropy->bitstate.bits_left = 0;
/* Advance past the RSTn marker */
- if (! (*cinfo->marker->read_restart_marker) (cinfo))
+ if (!(*cinfo->marker->read_restart_marker) (cinfo))
return FALSE;
/* Re-initialize DC predictions to 0 */
/*
* Huffman MCU decoding.
* Each of these routines decodes and returns one MCU's worth of
- * Huffman-compressed coefficients.
+ * Huffman-compressed coefficients.
* The coefficients are reordered from zigzag order into natural array order,
* but are not dequantized.
*
*/
METHODDEF(boolean)
-decode_mcu_DC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+decode_mcu_DC_first(j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
int Al = cinfo->Al;
register int s, r;
int blkn, ci;
JBLOCKROW block;
BITREAD_STATE_VARS;
savable_state state;
- d_derived_tbl * tbl;
- jpeg_component_info * compptr;
+ d_derived_tbl *tbl;
+ 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;
+ if (!process_restart(cinfo))
+ return FALSE;
}
/* If we've run out of data, just leave the MCU set to zeroes.
* This way, we return uniform gray for the remainder of the segment.
*/
- if (! entropy->pub.insufficient_data) {
+ if (!entropy->pub.insufficient_data) {
/* Load up working state */
- BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
+ BITREAD_LOAD_STATE(cinfo, entropy->bitstate);
ASSIGN_STATE(state, entropy->saved);
/* Outer loop handles each block in the MCU */
/* Section F.2.2.1: decode the DC coefficient difference */
HUFF_DECODE(s, br_state, tbl, return FALSE, label1);
if (s) {
- CHECK_BIT_BUFFER(br_state, s, return FALSE);
- r = GET_BITS(s);
- s = HUFF_EXTEND(r, s);
+ CHECK_BIT_BUFFER(br_state, s, return FALSE);
+ r = GET_BITS(s);
+ s = HUFF_EXTEND(r, s);
}
/* Convert DC difference to actual value, update last_dc_val */
+ if ((state.last_dc_val[ci] >= 0 &&
+ s > INT_MAX - state.last_dc_val[ci]) ||
+ (state.last_dc_val[ci] < 0 && s < INT_MIN - state.last_dc_val[ci]))
+ ERREXIT(cinfo, JERR_BAD_DCT_COEF);
s += state.last_dc_val[ci];
state.last_dc_val[ci] = s;
/* Scale and output the coefficient (assumes jpeg_natural_order[0]=0) */
- (*block)[0] = (JCOEF) (s << Al);
+ (*block)[0] = (JCOEF)LEFT_SHIFT(s, Al);
}
/* Completed MCU, so update state */
- BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
+ BITREAD_SAVE_STATE(cinfo, entropy->bitstate);
ASSIGN_STATE(entropy->saved, state);
}
*/
METHODDEF(boolean)
-decode_mcu_AC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+decode_mcu_AC_first(j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
int Se = cinfo->Se;
int Al = cinfo->Al;
register int s, k, r;
unsigned int EOBRUN;
JBLOCKROW block;
BITREAD_STATE_VARS;
- d_derived_tbl * tbl;
+ d_derived_tbl *tbl;
/* 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;
+ if (!process_restart(cinfo))
+ return FALSE;
}
/* If we've run out of data, just leave the MCU set to zeroes.
* This way, we return uniform gray for the remainder of the segment.
*/
- if (! entropy->pub.insufficient_data) {
+ if (!entropy->pub.insufficient_data) {
/* Load up working state.
* We can avoid loading/saving bitread state if in an EOB run.
*/
- EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */
+ EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */
/* There is always only one block per MCU */
- if (EOBRUN > 0) /* if it's a band of zeroes... */
- EOBRUN--; /* ...process it now (we do nothing) */
+ if (EOBRUN > 0) /* if it's a band of zeroes... */
+ EOBRUN--; /* ...process it now (we do nothing) */
else {
- BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
+ BITREAD_LOAD_STATE(cinfo, entropy->bitstate);
block = MCU_data[0];
tbl = entropy->ac_derived_tbl;
for (k = cinfo->Ss; k <= Se; k++) {
- HUFF_DECODE(s, br_state, tbl, 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);
- /* Scale and output coefficient in natural (dezigzagged) order */
- (*block)[jpeg_natural_order[k]] = (JCOEF) (s << Al);
- } else {
- if (r == 15) { /* ZRL */
- k += 15; /* skip 15 zeroes in band */
- } else { /* EOBr, run length is 2^r + appended bits */
- EOBRUN = 1 << r;
- if (r) { /* EOBr, r > 0 */
- CHECK_BIT_BUFFER(br_state, r, return FALSE);
- r = GET_BITS(r);
- EOBRUN += r;
- }
- EOBRUN--; /* this band is processed at this moment */
- break; /* force end-of-band */
- }
- }
+ HUFF_DECODE(s, br_state, tbl, 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);
+ /* Scale and output coefficient in natural (dezigzagged) order */
+ (*block)[jpeg_natural_order[k]] = (JCOEF)LEFT_SHIFT(s, Al);
+ } else {
+ if (r == 15) { /* ZRL */
+ k += 15; /* skip 15 zeroes in band */
+ } else { /* EOBr, run length is 2^r + appended bits */
+ EOBRUN = 1 << r;
+ if (r) { /* EOBr, r > 0 */
+ CHECK_BIT_BUFFER(br_state, r, return FALSE);
+ r = GET_BITS(r);
+ EOBRUN += r;
+ }
+ EOBRUN--; /* this band is processed at this moment */
+ break; /* force end-of-band */
+ }
+ }
}
- BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
+ BITREAD_SAVE_STATE(cinfo, entropy->bitstate);
}
/* Completed MCU, so update state */
- entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */
+ entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */
}
/* Account for restart interval (no-op if not using restarts) */
*/
METHODDEF(boolean)
-decode_mcu_DC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
+decode_mcu_DC_refine(j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
+ int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
int blkn;
JBLOCKROW block;
BITREAD_STATE_VARS;
/* 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;
+ if (!process_restart(cinfo))
+ return FALSE;
}
/* Not worth the cycles to check insufficient_data here,
*/
/* Load up working state */
- BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
+ BITREAD_LOAD_STATE(cinfo, entropy->bitstate);
/* Outer loop handles each block in the MCU */
}
/* Completed MCU, so update state */
- BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
+ BITREAD_SAVE_STATE(cinfo, entropy->bitstate);
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
*/
METHODDEF(boolean)
-decode_mcu_AC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+decode_mcu_AC_refine(j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr)cinfo->entropy;
int Se = cinfo->Se;
- int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
- int m1 = (-1) << cinfo->Al; /* -1 in the bit position being coded */
+ int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
+ int m1 = (NEG_1) << cinfo->Al; /* -1 in the bit position being coded */
register int s, k, r;
unsigned int EOBRUN;
JBLOCKROW block;
JCOEFPTR thiscoef;
BITREAD_STATE_VARS;
- d_derived_tbl * tbl;
+ d_derived_tbl *tbl;
int num_newnz;
int newnz_pos[DCTSIZE2];
/* 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;
+ if (!process_restart(cinfo))
+ return FALSE;
}
/* If we've run out of data, don't modify the MCU.
*/
- if (! entropy->pub.insufficient_data) {
+ if (!entropy->pub.insufficient_data) {
/* Load up working state */
- BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
+ BITREAD_LOAD_STATE(cinfo, entropy->bitstate);
EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */
/* There is always only one block per MCU */
if (EOBRUN == 0) {
for (; k <= Se; k++) {
- HUFF_DECODE(s, br_state, tbl, goto undoit, label3);
- r = s >> 4;
- s &= 15;
- if (s) {
- if (s != 1) /* size of new coef should always be 1 */
- WARNMS(cinfo, JWRN_HUFF_BAD_CODE);
- CHECK_BIT_BUFFER(br_state, 1, goto undoit);
- if (GET_BITS(1))
- s = p1; /* newly nonzero coef is positive */
- else
- s = m1; /* newly nonzero coef is negative */
- } else {
- if (r != 15) {
- EOBRUN = 1 << r; /* EOBr, run length is 2^r + appended bits */
- if (r) {
- CHECK_BIT_BUFFER(br_state, r, goto undoit);
- r = GET_BITS(r);
- EOBRUN += r;
- }
- break; /* rest of block is handled by EOB logic */
- }
- /* note s = 0 for processing ZRL */
- }
- /* Advance over already-nonzero coefs and r still-zero coefs,
- * appending correction bits to the nonzeroes. A correction bit is 1
- * if the absolute value of the coefficient must be increased.
- */
- do {
- thiscoef = *block + jpeg_natural_order[k];
- if (*thiscoef != 0) {
- CHECK_BIT_BUFFER(br_state, 1, goto undoit);
- if (GET_BITS(1)) {
- if ((*thiscoef & p1) == 0) { /* do nothing if already set it */
- if (*thiscoef >= 0)
- *thiscoef += p1;
- else
- *thiscoef += m1;
- }
- }
- } else {
- if (--r < 0)
- break; /* reached target zero coefficient */
- }
- k++;
- } while (k <= Se);
- if (s) {
- int pos = jpeg_natural_order[k];
- /* Output newly nonzero coefficient */
- (*block)[pos] = (JCOEF) s;
- /* Remember its position in case we have to suspend */
- newnz_pos[num_newnz++] = pos;
- }
+ HUFF_DECODE(s, br_state, tbl, goto undoit, label3);
+ r = s >> 4;
+ s &= 15;
+ if (s) {
+ if (s != 1) /* size of new coef should always be 1 */
+ WARNMS(cinfo, JWRN_HUFF_BAD_CODE);
+ CHECK_BIT_BUFFER(br_state, 1, goto undoit);
+ if (GET_BITS(1))
+ s = p1; /* newly nonzero coef is positive */
+ else
+ s = m1; /* newly nonzero coef is negative */
+ } else {
+ if (r != 15) {
+ EOBRUN = 1 << r; /* EOBr, run length is 2^r + appended bits */
+ if (r) {
+ CHECK_BIT_BUFFER(br_state, r, goto undoit);
+ r = GET_BITS(r);
+ EOBRUN += r;
+ }
+ break; /* rest of block is handled by EOB logic */
+ }
+ /* note s = 0 for processing ZRL */
+ }
+ /* Advance over already-nonzero coefs and r still-zero coefs,
+ * appending correction bits to the nonzeroes. A correction bit is 1
+ * if the absolute value of the coefficient must be increased.
+ */
+ do {
+ thiscoef = *block + jpeg_natural_order[k];
+ if (*thiscoef != 0) {
+ CHECK_BIT_BUFFER(br_state, 1, goto undoit);
+ if (GET_BITS(1)) {
+ if ((*thiscoef & p1) == 0) { /* do nothing if already set it */
+ if (*thiscoef >= 0)
+ *thiscoef += p1;
+ else
+ *thiscoef += m1;
+ }
+ }
+ } else {
+ if (--r < 0)
+ break; /* reached target zero coefficient */
+ }
+ k++;
+ } while (k <= Se);
+ if (s) {
+ int pos = jpeg_natural_order[k];
+ /* Output newly nonzero coefficient */
+ (*block)[pos] = (JCOEF)s;
+ /* Remember its position in case we have to suspend */
+ newnz_pos[num_newnz++] = pos;
+ }
}
}
* if the absolute value of the coefficient must be increased.
*/
for (; k <= Se; k++) {
- thiscoef = *block + jpeg_natural_order[k];
- if (*thiscoef != 0) {
- CHECK_BIT_BUFFER(br_state, 1, goto undoit);
- if (GET_BITS(1)) {
- if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */
- if (*thiscoef >= 0)
- *thiscoef += p1;
- else
- *thiscoef += m1;
- }
- }
- }
+ thiscoef = *block + jpeg_natural_order[k];
+ if (*thiscoef != 0) {
+ CHECK_BIT_BUFFER(br_state, 1, goto undoit);
+ if (GET_BITS(1)) {
+ if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */
+ if (*thiscoef >= 0)
+ *thiscoef += p1;
+ else
+ *thiscoef += m1;
+ }
+ }
+ }
}
/* Count one block completed in EOB run */
EOBRUN--;
}
/* Completed MCU, so update state */
- BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
+ BITREAD_SAVE_STATE(cinfo, entropy->bitstate);
entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */
}
*/
GLOBAL(void)
-jinit_phuff_decoder (j_decompress_ptr cinfo)
+jinit_phuff_decoder(j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy;
int *coef_bit_ptr;
int ci, i;
entropy = (phuff_entropy_ptr)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- SIZEOF(phuff_entropy_decoder));
- cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ sizeof(phuff_entropy_decoder));
+ cinfo->entropy = (struct jpeg_entropy_decoder *)entropy;
entropy->pub.start_pass = start_pass_phuff_decoder;
/* Mark derived tables unallocated */
/* Create progression status table */
cinfo->coef_bits = (int (*)[DCTSIZE2])
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- cinfo->num_components*DCTSIZE2*SIZEOF(int));
- coef_bit_ptr = & cinfo->coef_bits[0][0];
- for (ci = 0; ci < cinfo->num_components; ci++)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ cinfo->num_components * DCTSIZE2 *
+ sizeof(int));
+ coef_bit_ptr = &cinfo->coef_bits[0][0];
+ for (ci = 0; ci < cinfo->num_components; ci++)
for (i = 0; i < DCTSIZE2; i++)
*coef_bit_ptr++ = -1;
}
projects / platform / upstream / libjpeg-turbo.git / blobdiff