+++ /dev/null
-/*
- * jcphuff.c
- *
- * 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.
- *
- * This file contains Huffman entropy encoding routines for progressive JPEG.
- *
- * We do not support output suspension in this module, since the library
- * currently does not allow multiple-scan files to be written with output
- * suspension.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-#include "jchuff.h" /* Declarations shared with jchuff.c */
-
-#ifdef C_PROGRESSIVE_SUPPORTED
-
-/* Expanded entropy encoder object for progressive Huffman encoding. */
-
-typedef struct {
- struct jpeg_entropy_encoder pub; /* public fields */
-
- /* Mode flag: TRUE for optimization, FALSE for actual data output */
- boolean gather_statistics;
-
- /* Bit-level coding status.
- * next_output_byte/free_in_buffer are local copies of cinfo->dest fields.
- */
- JOCTET * next_output_byte; /* => next byte to write in buffer */
- size_t free_in_buffer; /* # of byte spaces remaining in buffer */
- INT32 put_buffer; /* current bit-accumulation buffer */
- int put_bits; /* # of bits now in it */
- j_compress_ptr cinfo; /* link to cinfo (needed for dump_buffer) */
-
- /* Coding status for DC components */
- int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
-
- /* Coding status for AC components */
- int ac_tbl_no; /* the table number of the single component */
- unsigned int EOBRUN; /* run length of EOBs */
- unsigned int BE; /* # of buffered correction bits before MCU */
- char * bit_buffer; /* buffer for correction bits (1 per char) */
- /* packing correction bits tightly would save some space but cost time... */
-
- unsigned int restarts_to_go; /* MCUs left in this restart interval */
- int next_restart_num; /* next restart number to write (0-7) */
-
- /* Pointers to derived tables (these workspaces have image lifespan).
- * Since any one scan codes only DC or only AC, we only need one set
- * of tables, not one for DC and one for AC.
- */
- c_derived_tbl * derived_tbls[NUM_HUFF_TBLS];
-
- /* Statistics tables for optimization; again, one set is enough */
- long * count_ptrs[NUM_HUFF_TBLS];
-} phuff_entropy_encoder;
-
-typedef phuff_entropy_encoder * phuff_entropy_ptr;
-
-/* MAX_CORR_BITS is the number of bits the AC refinement correction-bit
- * buffer can hold. Larger sizes may slightly improve compression, but
- * 1000 is already well into the realm of overkill.
- * The minimum safe size is 64 bits.
- */
-
-#define MAX_CORR_BITS 1000 /* Max # of correction bits I can buffer */
-
-/* IRIGHT_SHIFT is like RIGHT_SHIFT, but works on int rather than INT32.
- * We assume that int right shift is unsigned if INT32 right shift is,
- * which should be safe.
- */
-
-#ifdef RIGHT_SHIFT_IS_UNSIGNED
-#define ISHIFT_TEMPS int ishift_temp;
-#define IRIGHT_SHIFT(x,shft) \
- ((ishift_temp = (x)) < 0 ? \
- (ishift_temp >> (shft)) | ((~0) << (16-(shft))) : \
- (ishift_temp >> (shft)))
-#else
-#define ISHIFT_TEMPS
-#define IRIGHT_SHIFT(x,shft) ((x) >> (shft))
-#endif
-
-/* Forward declarations */
-METHODDEF(boolean) encode_mcu_DC_first JPP((j_compress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) encode_mcu_AC_first JPP((j_compress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) encode_mcu_DC_refine JPP((j_compress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(boolean) encode_mcu_AC_refine JPP((j_compress_ptr cinfo,
- JBLOCKROW *MCU_data));
-METHODDEF(void) finish_pass_phuff JPP((j_compress_ptr cinfo));
-METHODDEF(void) finish_pass_gather_phuff JPP((j_compress_ptr cinfo));
-
-
-/*
- * Initialize for a Huffman-compressed scan using progressive JPEG.
- */
-
-METHODDEF(void)
-start_pass_phuff (j_compress_ptr cinfo, boolean gather_statistics)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- boolean is_DC_band;
- int ci, tbl;
- jpeg_component_info * compptr;
-
- entropy->cinfo = cinfo;
- entropy->gather_statistics = gather_statistics;
-
- is_DC_band = (cinfo->Ss == 0);
-
- /* We assume jcmaster.c already validated the scan parameters. */
-
- /* Select execution routines */
- if (cinfo->Ah == 0) {
- if (is_DC_band)
- entropy->pub.encode_mcu = encode_mcu_DC_first;
- else
- entropy->pub.encode_mcu = encode_mcu_AC_first;
- } else {
- if (is_DC_band)
- entropy->pub.encode_mcu = encode_mcu_DC_refine;
- else {
- entropy->pub.encode_mcu = encode_mcu_AC_refine;
- /* AC refinement needs a correction bit buffer */
- if (entropy->bit_buffer == NULL)
- entropy->bit_buffer = (char *)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- MAX_CORR_BITS * SIZEOF(char));
- }
- }
- if (gather_statistics)
- entropy->pub.finish_pass = finish_pass_gather_phuff;
- else
- entropy->pub.finish_pass = finish_pass_phuff;
-
- /* Only DC coefficients may be interleaved, so cinfo->comps_in_scan = 1
- * for AC coefficients.
- */
- for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
- compptr = cinfo->cur_comp_info[ci];
- /* Initialize DC predictions to 0 */
- entropy->last_dc_val[ci] = 0;
- /* Get table index */
- if (is_DC_band) {
- if (cinfo->Ah != 0) /* DC refinement needs no table */
- continue;
- tbl = compptr->dc_tbl_no;
- } else {
- entropy->ac_tbl_no = tbl = compptr->ac_tbl_no;
- }
- if (gather_statistics) {
- /* Check for invalid table index */
- /* (make_c_derived_tbl does this in the other path) */
- if (tbl < 0 || tbl >= NUM_HUFF_TBLS)
- ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);
- /* Allocate and zero the statistics tables */
- /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */
- if (entropy->count_ptrs[tbl] == NULL)
- entropy->count_ptrs[tbl] = (long *)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- 257 * SIZEOF(long));
- MEMZERO(entropy->count_ptrs[tbl], 257 * SIZEOF(long));
- } else {
- /* Compute derived values for Huffman table */
- /* We may do this more than once for a table, but it's not expensive */
- jpeg_make_c_derived_tbl(cinfo, is_DC_band, tbl,
- & entropy->derived_tbls[tbl]);
- }
- }
-
- /* Initialize AC stuff */
- entropy->EOBRUN = 0;
- entropy->BE = 0;
-
- /* Initialize bit buffer to empty */
- entropy->put_buffer = 0;
- entropy->put_bits = 0;
-
- /* Initialize restart stuff */
- entropy->restarts_to_go = cinfo->restart_interval;
- entropy->next_restart_num = 0;
-}
-
-
-/* Outputting bytes to the file.
- * NB: these must be called only when actually outputting,
- * that is, entropy->gather_statistics == FALSE.
- */
-
-/* Emit a byte */
-#define emit_byte(entropy,val) \
- { *(entropy)->next_output_byte++ = (JOCTET) (val); \
- if (--(entropy)->free_in_buffer == 0) \
- dump_buffer(entropy); }
-
-
-LOCAL(void)
-dump_buffer (phuff_entropy_ptr entropy)
-/* Empty the output buffer; we do not support suspension in this module. */
-{
- struct jpeg_destination_mgr * dest = entropy->cinfo->dest;
-
- if (! (*dest->empty_output_buffer) (entropy->cinfo))
- ERREXIT(entropy->cinfo, JERR_CANT_SUSPEND);
- /* After a successful buffer dump, must reset buffer pointers */
- entropy->next_output_byte = dest->next_output_byte;
- entropy->free_in_buffer = dest->free_in_buffer;
-}
-
-
-/* Outputting bits to the file */
-
-/* Only the right 24 bits of put_buffer are used; the valid bits are
- * left-justified in this part. At most 16 bits can be passed to emit_bits
- * in one call, and we never retain more than 7 bits in put_buffer
- * between calls, so 24 bits are sufficient.
- */
-
-INLINE
-LOCAL(void)
-emit_bits (phuff_entropy_ptr entropy, unsigned int code, int size)
-/* Emit some bits, unless we are in gather mode */
-{
- /* This routine is heavily used, so it's worth coding tightly. */
- register INT32 put_buffer = (INT32) code;
- register int put_bits = entropy->put_bits;
-
- /* if size is 0, caller used an invalid Huffman table entry */
- if (size == 0)
- ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE);
-
- if (entropy->gather_statistics)
- return; /* do nothing if we're only getting stats */
-
- put_buffer &= (((INT32) 1)<<size) - 1; /* mask off any extra bits in code */
-
- put_bits += size; /* new number of bits in buffer */
-
- put_buffer <<= 24 - put_bits; /* align incoming bits */
-
- put_buffer |= entropy->put_buffer; /* and merge with old buffer contents */
-
- while (put_bits >= 8) {
- int c = (int) ((put_buffer >> 16) & 0xFF);
-
- emit_byte(entropy, c);
- if (c == 0xFF) { /* need to stuff a zero byte? */
- emit_byte(entropy, 0);
- }
- put_buffer <<= 8;
- put_bits -= 8;
- }
-
- entropy->put_buffer = put_buffer; /* update variables */
- entropy->put_bits = put_bits;
-}
-
-
-LOCAL(void)
-flush_bits (phuff_entropy_ptr entropy)
-{
- emit_bits(entropy, 0x7F, 7); /* fill any partial byte with ones */
- entropy->put_buffer = 0; /* and reset bit-buffer to empty */
- entropy->put_bits = 0;
-}
-
-
-/*
- * Emit (or just count) a Huffman symbol.
- */
-
-INLINE
-LOCAL(void)
-emit_symbol (phuff_entropy_ptr entropy, int tbl_no, int symbol)
-{
- if (entropy->gather_statistics)
- entropy->count_ptrs[tbl_no][symbol]++;
- else {
- c_derived_tbl * tbl = entropy->derived_tbls[tbl_no];
- emit_bits(entropy, tbl->ehufco[symbol], tbl->ehufsi[symbol]);
- }
-}
-
-
-/*
- * Emit bits from a correction bit buffer.
- */
-
-LOCAL(void)
-emit_buffered_bits (phuff_entropy_ptr entropy, char * bufstart,
- unsigned int nbits)
-{
- if (entropy->gather_statistics)
- return; /* no real work */
-
- while (nbits > 0) {
- emit_bits(entropy, (unsigned int) (*bufstart), 1);
- bufstart++;
- nbits--;
- }
-}
-
-
-/*
- * Emit any pending EOBRUN symbol.
- */
-
-LOCAL(void)
-emit_eobrun (phuff_entropy_ptr entropy)
-{
- register int temp, nbits;
-
- if (entropy->EOBRUN > 0) { /* if there is any pending EOBRUN */
- temp = entropy->EOBRUN;
- nbits = 0;
- while ((temp >>= 1))
- nbits++;
- /* safety check: shouldn't happen given limited correction-bit buffer */
- if (nbits > 14)
- ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE);
-
- emit_symbol(entropy, entropy->ac_tbl_no, nbits << 4);
- if (nbits)
- emit_bits(entropy, entropy->EOBRUN, nbits);
-
- entropy->EOBRUN = 0;
-
- /* Emit any buffered correction bits */
- emit_buffered_bits(entropy, entropy->bit_buffer, entropy->BE);
- entropy->BE = 0;
- }
-}
-
-
-/*
- * Emit a restart marker & resynchronize predictions.
- */
-
-LOCAL(void)
-emit_restart (phuff_entropy_ptr entropy, int restart_num)
-{
- int ci;
-
- emit_eobrun(entropy);
-
- if (! entropy->gather_statistics) {
- flush_bits(entropy);
- emit_byte(entropy, 0xFF);
- emit_byte(entropy, JPEG_RST0 + restart_num);
- }
-
- if (entropy->cinfo->Ss == 0) {
- /* Re-initialize DC predictions to 0 */
- for (ci = 0; ci < entropy->cinfo->comps_in_scan; ci++)
- entropy->last_dc_val[ci] = 0;
- } else {
- /* Re-initialize all AC-related fields to 0 */
- entropy->EOBRUN = 0;
- entropy->BE = 0;
- }
-}
-
-
-/*
- * MCU encoding for DC initial scan (either spectral selection,
- * or first pass of successive approximation).
- */
-
-METHODDEF(boolean)
-encode_mcu_DC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- register int temp, temp2;
- register int nbits;
- int blkn, ci;
- int Al = cinfo->Al;
- JBLOCKROW block;
- jpeg_component_info * compptr;
- ISHIFT_TEMPS
-
- entropy->next_output_byte = cinfo->dest->next_output_byte;
- entropy->free_in_buffer = cinfo->dest->free_in_buffer;
-
- /* Emit restart marker if needed */
- if (cinfo->restart_interval)
- if (entropy->restarts_to_go == 0)
- emit_restart(entropy, entropy->next_restart_num);
-
- /* Encode the MCU data blocks */
- for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
- block = MCU_data[blkn];
- ci = cinfo->MCU_membership[blkn];
- compptr = cinfo->cur_comp_info[ci];
-
- /* Compute the DC value after the required point transform by Al.
- * This is simply an arithmetic right shift.
- */
- temp2 = IRIGHT_SHIFT((int) ((*block)[0]), Al);
-
- /* DC differences are figured on the point-transformed values. */
- temp = temp2 - entropy->last_dc_val[ci];
- entropy->last_dc_val[ci] = temp2;
-
- /* Encode the DC coefficient difference per section G.1.2.1 */
- temp2 = temp;
- if (temp < 0) {
- temp = -temp; /* temp is abs value of input */
- /* For a negative input, want temp2 = bitwise complement of abs(input) */
- /* This code assumes we are on a two's complement machine */
- temp2--;
- }
-
- /* Find the number of bits needed for the magnitude of the coefficient */
- nbits = 0;
- while (temp) {
- nbits++;
- temp >>= 1;
- }
- /* Check for out-of-range coefficient values.
- * Since we're encoding a difference, the range limit is twice as much.
- */
- if (nbits > MAX_COEF_BITS+1)
- ERREXIT(cinfo, JERR_BAD_DCT_COEF);
-
- /* Count/emit the Huffman-coded symbol for the number of bits */
- emit_symbol(entropy, compptr->dc_tbl_no, nbits);
-
- /* Emit that number of bits of the value, if positive, */
- /* or the complement of its magnitude, if negative. */
- if (nbits) /* emit_bits rejects calls with size 0 */
- emit_bits(entropy, (unsigned int) temp2, nbits);
- }
-
- cinfo->dest->next_output_byte = entropy->next_output_byte;
- cinfo->dest->free_in_buffer = entropy->free_in_buffer;
-
- /* Update restart-interval state too */
- if (cinfo->restart_interval) {
- if (entropy->restarts_to_go == 0) {
- entropy->restarts_to_go = cinfo->restart_interval;
- entropy->next_restart_num++;
- entropy->next_restart_num &= 7;
- }
- entropy->restarts_to_go--;
- }
-
- return TRUE;
-}
-
-
-/*
- * MCU encoding for AC initial scan (either spectral selection,
- * or first pass of successive approximation).
- */
-
-METHODDEF(boolean)
-encode_mcu_AC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- register int temp, temp2;
- register int nbits;
- register int r, k;
- int Se = cinfo->Se;
- int Al = cinfo->Al;
- JBLOCKROW block;
-
- entropy->next_output_byte = cinfo->dest->next_output_byte;
- entropy->free_in_buffer = cinfo->dest->free_in_buffer;
-
- /* Emit restart marker if needed */
- if (cinfo->restart_interval)
- if (entropy->restarts_to_go == 0)
- emit_restart(entropy, entropy->next_restart_num);
-
- /* Encode the MCU data block */
- block = MCU_data[0];
-
- /* Encode the AC coefficients per section G.1.2.2, fig. G.3 */
-
- r = 0; /* r = run length of zeros */
-
- for (k = cinfo->Ss; k <= Se; k++) {
- if ((temp = (*block)[jpeg_natural_order[k]]) == 0) {
- r++;
- continue;
- }
- /* We must apply the point transform by Al. For AC coefficients this
- * is an integer division with rounding towards 0. To do this portably
- * in C, we shift after obtaining the absolute value; so the code is
- * interwoven with finding the abs value (temp) and output bits (temp2).
- */
- if (temp < 0) {
- temp = -temp; /* temp is abs value of input */
- temp >>= Al; /* apply the point transform */
- /* For a negative coef, want temp2 = bitwise complement of abs(coef) */
- temp2 = ~temp;
- } else {
- temp >>= Al; /* apply the point transform */
- temp2 = temp;
- }
- /* Watch out for case that nonzero coef is zero after point transform */
- if (temp == 0) {
- r++;
- continue;
- }
-
- /* Emit any pending EOBRUN */
- if (entropy->EOBRUN > 0)
- emit_eobrun(entropy);
- /* if run length > 15, must emit special run-length-16 codes (0xF0) */
- while (r > 15) {
- emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);
- r -= 16;
- }
-
- /* Find the number of bits needed for the magnitude of the coefficient */
- nbits = 1; /* there must be at least one 1 bit */
- while ((temp >>= 1))
- nbits++;
- /* Check for out-of-range coefficient values */
- if (nbits > MAX_COEF_BITS)
- ERREXIT(cinfo, JERR_BAD_DCT_COEF);
-
- /* Count/emit Huffman symbol for run length / number of bits */
- emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + nbits);
-
- /* Emit that number of bits of the value, if positive, */
- /* or the complement of its magnitude, if negative. */
- emit_bits(entropy, (unsigned int) temp2, nbits);
-
- r = 0; /* reset zero run length */
- }
-
- if (r > 0) { /* If there are trailing zeroes, */
- entropy->EOBRUN++; /* count an EOB */
- if (entropy->EOBRUN == 0x7FFF)
- emit_eobrun(entropy); /* force it out to avoid overflow */
- }
-
- cinfo->dest->next_output_byte = entropy->next_output_byte;
- cinfo->dest->free_in_buffer = entropy->free_in_buffer;
-
- /* Update restart-interval state too */
- if (cinfo->restart_interval) {
- if (entropy->restarts_to_go == 0) {
- entropy->restarts_to_go = cinfo->restart_interval;
- entropy->next_restart_num++;
- entropy->next_restart_num &= 7;
- }
- entropy->restarts_to_go--;
- }
-
- return TRUE;
-}
-
-
-/*
- * MCU encoding for DC successive approximation refinement scan.
- * Note: we assume such scans can be multi-component, although the spec
- * is not very clear on the point.
- */
-
-METHODDEF(boolean)
-encode_mcu_DC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- register int temp;
- int blkn;
- int Al = cinfo->Al;
- JBLOCKROW block;
-
- entropy->next_output_byte = cinfo->dest->next_output_byte;
- entropy->free_in_buffer = cinfo->dest->free_in_buffer;
-
- /* Emit restart marker if needed */
- if (cinfo->restart_interval)
- if (entropy->restarts_to_go == 0)
- emit_restart(entropy, entropy->next_restart_num);
-
- /* Encode the MCU data blocks */
- for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
- block = MCU_data[blkn];
-
- /* We simply emit the Al'th bit of the DC coefficient value. */
- temp = (*block)[0];
- emit_bits(entropy, (unsigned int) (temp >> Al), 1);
- }
-
- cinfo->dest->next_output_byte = entropy->next_output_byte;
- cinfo->dest->free_in_buffer = entropy->free_in_buffer;
-
- /* Update restart-interval state too */
- if (cinfo->restart_interval) {
- if (entropy->restarts_to_go == 0) {
- entropy->restarts_to_go = cinfo->restart_interval;
- entropy->next_restart_num++;
- entropy->next_restart_num &= 7;
- }
- entropy->restarts_to_go--;
- }
-
- return TRUE;
-}
-
-
-/*
- * MCU encoding for AC successive approximation refinement scan.
- */
-
-METHODDEF(boolean)
-encode_mcu_AC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- register int temp;
- register int r, k;
- int EOB;
- char *BR_buffer;
- unsigned int BR;
- int Se = cinfo->Se;
- int Al = cinfo->Al;
- JBLOCKROW block;
- int absvalues[DCTSIZE2];
-
- entropy->next_output_byte = cinfo->dest->next_output_byte;
- entropy->free_in_buffer = cinfo->dest->free_in_buffer;
-
- /* Emit restart marker if needed */
- if (cinfo->restart_interval)
- if (entropy->restarts_to_go == 0)
- emit_restart(entropy, entropy->next_restart_num);
-
- /* Encode the MCU data block */
- block = MCU_data[0];
-
- /* It is convenient to make a pre-pass to determine the transformed
- * coefficients' absolute values and the EOB position.
- */
- EOB = 0;
- for (k = cinfo->Ss; k <= Se; k++) {
- temp = (*block)[jpeg_natural_order[k]];
- /* We must apply the point transform by Al. For AC coefficients this
- * is an integer division with rounding towards 0. To do this portably
- * in C, we shift after obtaining the absolute value.
- */
- if (temp < 0)
- temp = -temp; /* temp is abs value of input */
- temp >>= Al; /* apply the point transform */
- absvalues[k] = temp; /* save abs value for main pass */
- if (temp == 1)
- EOB = k; /* EOB = index of last newly-nonzero coef */
- }
-
- /* Encode the AC coefficients per section G.1.2.3, fig. G.7 */
-
- r = 0; /* r = run length of zeros */
- BR = 0; /* BR = count of buffered bits added now */
- BR_buffer = entropy->bit_buffer + entropy->BE; /* Append bits to buffer */
-
- for (k = cinfo->Ss; k <= Se; k++) {
- if ((temp = absvalues[k]) == 0) {
- r++;
- continue;
- }
-
- /* Emit any required ZRLs, but not if they can be folded into EOB */
- while (r > 15 && k <= EOB) {
- /* emit any pending EOBRUN and the BE correction bits */
- emit_eobrun(entropy);
- /* Emit ZRL */
- emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);
- r -= 16;
- /* Emit buffered correction bits that must be associated with ZRL */
- emit_buffered_bits(entropy, BR_buffer, BR);
- BR_buffer = entropy->bit_buffer; /* BE bits are gone now */
- BR = 0;
- }
-
- /* If the coef was previously nonzero, it only needs a correction bit.
- * NOTE: a straight translation of the spec's figure G.7 would suggest
- * that we also need to test r > 15. But if r > 15, we can only get here
- * if k > EOB, which implies that this coefficient is not 1.
- */
- if (temp > 1) {
- /* The correction bit is the next bit of the absolute value. */
- BR_buffer[BR++] = (char) (temp & 1);
- continue;
- }
-
- /* Emit any pending EOBRUN and the BE correction bits */
- emit_eobrun(entropy);
-
- /* Count/emit Huffman symbol for run length / number of bits */
- emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + 1);
-
- /* Emit output bit for newly-nonzero coef */
- temp = ((*block)[jpeg_natural_order[k]] < 0) ? 0 : 1;
- emit_bits(entropy, (unsigned int) temp, 1);
-
- /* Emit buffered correction bits that must be associated with this code */
- emit_buffered_bits(entropy, BR_buffer, BR);
- BR_buffer = entropy->bit_buffer; /* BE bits are gone now */
- BR = 0;
- r = 0; /* reset zero run length */
- }
-
- if (r > 0 || BR > 0) { /* If there are trailing zeroes, */
- entropy->EOBRUN++; /* count an EOB */
- entropy->BE += BR; /* concat my correction bits to older ones */
- /* We force out the EOB if we risk either:
- * 1. overflow of the EOB counter;
- * 2. overflow of the correction bit buffer during the next MCU.
- */
- if (entropy->EOBRUN == 0x7FFF || entropy->BE > (MAX_CORR_BITS-DCTSIZE2+1))
- emit_eobrun(entropy);
- }
-
- cinfo->dest->next_output_byte = entropy->next_output_byte;
- cinfo->dest->free_in_buffer = entropy->free_in_buffer;
-
- /* Update restart-interval state too */
- if (cinfo->restart_interval) {
- if (entropy->restarts_to_go == 0) {
- entropy->restarts_to_go = cinfo->restart_interval;
- entropy->next_restart_num++;
- entropy->next_restart_num &= 7;
- }
- entropy->restarts_to_go--;
- }
-
- return TRUE;
-}
-
-
-/*
- * Finish up at the end of a Huffman-compressed progressive scan.
- */
-
-METHODDEF(void)
-finish_pass_phuff (j_compress_ptr cinfo)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
-
- entropy->next_output_byte = cinfo->dest->next_output_byte;
- entropy->free_in_buffer = cinfo->dest->free_in_buffer;
-
- /* Flush out any buffered data */
- emit_eobrun(entropy);
- flush_bits(entropy);
-
- cinfo->dest->next_output_byte = entropy->next_output_byte;
- cinfo->dest->free_in_buffer = entropy->free_in_buffer;
-}
-
-
-/*
- * Finish up a statistics-gathering pass and create the new Huffman tables.
- */
-
-METHODDEF(void)
-finish_pass_gather_phuff (j_compress_ptr cinfo)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- boolean is_DC_band;
- int ci, tbl;
- jpeg_component_info * compptr;
- JHUFF_TBL **htblptr;
- boolean did[NUM_HUFF_TBLS];
-
- /* Flush out buffered data (all we care about is counting the EOB symbol) */
- emit_eobrun(entropy);
-
- is_DC_band = (cinfo->Ss == 0);
-
- /* It's important not to apply jpeg_gen_optimal_table more than once
- * per table, because it clobbers the input frequency counts!
- */
- MEMZERO(did, SIZEOF(did));
-
- for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
- compptr = cinfo->cur_comp_info[ci];
- if (is_DC_band) {
- if (cinfo->Ah != 0) /* DC refinement needs no table */
- continue;
- tbl = compptr->dc_tbl_no;
- } else {
- tbl = compptr->ac_tbl_no;
- }
- if (! did[tbl]) {
- if (is_DC_band)
- htblptr = & cinfo->dc_huff_tbl_ptrs[tbl];
- else
- htblptr = & cinfo->ac_huff_tbl_ptrs[tbl];
- if (*htblptr == NULL)
- *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
- jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[tbl]);
- did[tbl] = TRUE;
- }
- }
-}
-
-
-/*
- * Module initialization routine for progressive Huffman entropy encoding.
- */
-
-GLOBAL(void)
-jinit_phuff_encoder (j_compress_ptr cinfo)
-{
- phuff_entropy_ptr entropy;
- int i;
-
- entropy = (phuff_entropy_ptr)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- SIZEOF(phuff_entropy_encoder));
- cinfo->entropy = (struct jpeg_entropy_encoder *) entropy;
- entropy->pub.start_pass = start_pass_phuff;
-
- /* Mark tables unallocated */
- for (i = 0; i < NUM_HUFF_TBLS; i++) {
- entropy->derived_tbls[i] = NULL;
- entropy->count_ptrs[i] = NULL;
- }
- entropy->bit_buffer = NULL; /* needed only in AC refinement scan */
-}
-
-#endif /* C_PROGRESSIVE_SUPPORTED */
projects / opencv / blobdiff