1 files changed, 587 insertions, 0 deletions
diff --git a/src/3rdparty/libjpeg/src/jclhuff.c b/src/3rdparty/libjpeg/src/jclhuff.c
new file mode 100644
index 0000000000..ae4154532e
--- /dev/null
+++ b/src/3rdparty/libjpeg/src/jclhuff.c
@@ -0,0 +1,587 @@
+/*
+ * jclhuff.c
+ *
+ * This file was part of the Independent JPEG Group's software:
+ * Copyright (C) 1991-1997, Thomas G. Lane.
+ * Lossless JPEG Modifications:
+ * Copyright (C) 1999, Ken Murchison.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 2022, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
+ *
+ * This file contains Huffman entropy encoding routines for lossless JPEG.
+ *
+ * Much of the complexity here has to do with supporting output suspension.
+ * If the data destination module demands suspension, we want to be able to
+ * back up to the start of the current MCU.  To do this, we copy state
+ * variables into local working storage, and update them back to the
+ * permanent JPEG objects only upon successful completion of an MCU.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jlossls.h"            /* Private declarations for lossless codec */
+#include "jchuff.h"             /* Declarations shared with jc*huff.c */
+
+
+#ifdef C_LOSSLESS_SUPPORTED
+
+/* The legal range of a spatial difference is
+ * -32767 .. +32768.
+ * Hence the magnitude should always fit in 16 bits.
+ */
+
+#define MAX_DIFF_BITS  16
+
+
+/* Expanded entropy encoder object for Huffman encoding in lossless mode.
+ *
+ * The savable_state subrecord contains fields that change within an MCU,
+ * but must not be updated permanently until we complete the MCU.
+ */
+
+typedef struct {
+  size_t put_buffer;            /* current bit-accumulation buffer */
+  int put_bits;                 /* # of bits now in it */
+} savable_state;
+
+
+typedef struct {
+  int ci, yoffset, MCU_width;
+} lhe_input_ptr_info;
+
+
+typedef struct {
+  struct jpeg_entropy_encoder pub; /* public fields */
+
+  savable_state saved;          /* Bit buffer at start of MCU */
+
+  /* These fields are NOT loaded into local working state. */
+  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) */
+  c_derived_tbl *derived_tbls[NUM_HUFF_TBLS];
+
+  /* Pointers to derived tables to be used for each data unit within an MCU */
+  c_derived_tbl *cur_tbls[C_MAX_BLOCKS_IN_MCU];
+
+#ifdef ENTROPY_OPT_SUPPORTED    /* Statistics tables for optimization */
+  long *count_ptrs[NUM_HUFF_TBLS];
+
+  /* Pointers to stats tables to be used for each data unit within an MCU */
+  long *cur_counts[C_MAX_BLOCKS_IN_MCU];
+#endif
+
+  /* Pointers to the proper input difference row for each group of data units
+   * within an MCU.  For each component, there are Vi groups of Hi data units.
+   */
+  JDIFFROW input_ptr[C_MAX_BLOCKS_IN_MCU];
+
+  /* Number of input pointers in use for the current MCU.  This is the sum
+   * of all Vi in the MCU.
+   */
+  int num_input_ptrs;
+
+  /* Information used for positioning the input pointers within the input
+   * difference rows.
+   */
+  lhe_input_ptr_info input_ptr_info[C_MAX_BLOCKS_IN_MCU];
+
+  /* Index of the proper input pointer for each data unit within an MCU */
+  int input_ptr_index[C_MAX_BLOCKS_IN_MCU];
+
+} lhuff_entropy_encoder;
+
+typedef lhuff_entropy_encoder *lhuff_entropy_ptr;
+
+/* Working state while writing an MCU.
+ * This struct contains all the fields that are needed by subroutines.
+ */
+
+typedef struct {
+  JOCTET *next_output_byte;     /* => next byte to write in buffer */
+  size_t free_in_buffer;        /* # of byte spaces remaining in buffer */
+  savable_state cur;            /* Current bit buffer & DC state */
+  j_compress_ptr cinfo;         /* dump_buffer needs access to this */
+} working_state;
+
+
+/* Forward declarations */
+METHODDEF(JDIMENSION) encode_mcus_huff(j_compress_ptr cinfo,
+                                       JDIFFIMAGE diff_buf,
+                                       JDIMENSION MCU_row_num,
+                                       JDIMENSION MCU_col_num,
+                                       JDIMENSION nMCU);
+METHODDEF(void) finish_pass_huff(j_compress_ptr cinfo);
+#ifdef ENTROPY_OPT_SUPPORTED
+METHODDEF(JDIMENSION) encode_mcus_gather(j_compress_ptr cinfo,
+                                         JDIFFIMAGE diff_buf,
+                                         JDIMENSION MCU_row_num,
+                                         JDIMENSION MCU_col_num,
+                                         JDIMENSION nMCU);
+METHODDEF(void) finish_pass_gather(j_compress_ptr cinfo);
+#endif
+
+
+/*
+ * Initialize for a Huffman-compressed scan.
+ * If gather_statistics is TRUE, we do not output anything during the scan,
+ * just count the Huffman symbols used and generate Huffman code tables.
+ */
+
+METHODDEF(void)
+start_pass_lhuff(j_compress_ptr cinfo, boolean gather_statistics)
+{
+  lhuff_entropy_ptr entropy = (lhuff_entropy_ptr)cinfo->entropy;
+  int ci, dctbl, sampn, ptrn, yoffset, xoffset;
+  jpeg_component_info *compptr;
+
+  if (gather_statistics) {
+#ifdef ENTROPY_OPT_SUPPORTED
+    entropy->pub.encode_mcus = encode_mcus_gather;
+    entropy->pub.finish_pass = finish_pass_gather;
+#else
+    ERREXIT(cinfo, JERR_NOT_COMPILED);
+#endif
+  } else {
+    entropy->pub.encode_mcus = encode_mcus_huff;
+    entropy->pub.finish_pass = finish_pass_huff;
+  }
+
+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
+    compptr = cinfo->cur_comp_info[ci];
+    dctbl = compptr->dc_tbl_no;
+    if (gather_statistics) {
+#ifdef ENTROPY_OPT_SUPPORTED
+      /* Check for invalid table indexes */
+      /* (make_c_derived_tbl does this in the other path) */
+      if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS)
+        ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);
+      /* Allocate and zero the statistics tables */
+      /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */
+      if (entropy->count_ptrs[dctbl] == NULL)
+        entropy->count_ptrs[dctbl] = (long *)
+          (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+                                      257 * sizeof(long));
+      memset(entropy->count_ptrs[dctbl], 0, 257 * sizeof(long));
+#endif
+    } else {
+      /* Compute derived values for Huffman tables */
+      /* We may do this more than once for a table, but it's not expensive */
+      jpeg_make_c_derived_tbl(cinfo, TRUE, dctbl,
+                              &entropy->derived_tbls[dctbl]);
+    }
+  }
+
+  /* Precalculate encoding info for each sample in an MCU of this scan */
+  for (sampn = 0, ptrn = 0; sampn < cinfo->blocks_in_MCU;) {
+    compptr = cinfo->cur_comp_info[cinfo->MCU_membership[sampn]];
+    ci = compptr->component_index;
+    for (yoffset = 0; yoffset < compptr->MCU_height; yoffset++, ptrn++) {
+      /* Precalculate the setup info for each input pointer */
+      entropy->input_ptr_info[ptrn].ci = ci;
+      entropy->input_ptr_info[ptrn].yoffset = yoffset;
+      entropy->input_ptr_info[ptrn].MCU_width = compptr->MCU_width;
+      for (xoffset = 0; xoffset < compptr->MCU_width; xoffset++, sampn++) {
+        /* Precalculate the input pointer index for each sample */
+        entropy->input_ptr_index[sampn] = ptrn;
+        /* Precalculate which tables to use for each sample */
+        entropy->cur_tbls[sampn] = entropy->derived_tbls[compptr->dc_tbl_no];
+        entropy->cur_counts[sampn] = entropy->count_ptrs[compptr->dc_tbl_no];
+      }
+    }
+  }
+  entropy->num_input_ptrs = ptrn;
+
+  /* Initialize bit buffer to empty */
+  entropy->saved.put_buffer = 0;
+  entropy->saved.put_bits = 0;
+
+  /* Initialize restart stuff */
+  entropy->restarts_to_go = cinfo->restart_interval;
+  entropy->next_restart_num = 0;
+}
+
+
+/* Outputting bytes to the file */
+
+/* Emit a byte, taking 'action' if must suspend. */
+#define emit_byte(state, val, action) { \
+  *(state)->next_output_byte++ = (JOCTET)(val); \
+  if (--(state)->free_in_buffer == 0) \
+    if (!dump_buffer(state)) \
+      { action; } \
+}
+
+
+LOCAL(boolean)
+dump_buffer(working_state *state)
+/* Empty the output buffer; return TRUE if successful, FALSE if must suspend */
+{
+  struct jpeg_destination_mgr *dest = state->cinfo->dest;
+
+  if (!(*dest->empty_output_buffer) (state->cinfo))
+    return FALSE;
+  /* After a successful buffer dump, must reset buffer pointers */
+  state->next_output_byte = dest->next_output_byte;
+  state->free_in_buffer = dest->free_in_buffer;
+  return TRUE;
+}
+
+
+/* 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(boolean)
+emit_bits(working_state *state, unsigned int code, int size)
+/* Emit some bits; return TRUE if successful, FALSE if must suspend */
+{
+  /* This routine is heavily used, so it's worth coding tightly. */
+  register size_t put_buffer = (size_t)code;
+  register int put_bits = state->cur.put_bits;
+
+  /* if size is 0, caller used an invalid Huffman table entry */
+  if (size == 0)
+    ERREXIT(state->cinfo, JERR_HUFF_MISSING_CODE);
+
+  put_buffer &= (((size_t)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 |= state->cur.put_buffer; /* and merge with old buffer contents */
+
+  while (put_bits >= 8) {
+    int c = (int)((put_buffer >> 16) & 0xFF);
+
+    emit_byte(state, c, return FALSE);
+    if (c == 0xFF) {            /* need to stuff a zero byte? */
+      emit_byte(state, 0, return FALSE);
+    }
+    put_buffer <<= 8;
+    put_bits -= 8;
+  }
+
+  state->cur.put_buffer = put_buffer; /* update state variables */
+  state->cur.put_bits = put_bits;
+
+  return TRUE;
+}
+
+
+LOCAL(boolean)
+flush_bits(working_state *state)
+{
+  if (!emit_bits(state, 0x7F, 7)) /* fill any partial byte with ones */
+    return FALSE;
+  state->cur.put_buffer = 0;    /* and reset bit-buffer to empty */
+  state->cur.put_bits = 0;
+  return TRUE;
+}
+
+
+/*
+ * Emit a restart marker & resynchronize predictions.
+ */
+
+LOCAL(boolean)
+emit_restart(working_state *state, int restart_num)
+{
+  if (!flush_bits(state))
+    return FALSE;
+
+  emit_byte(state, 0xFF, return FALSE);
+  emit_byte(state, JPEG_RST0 + restart_num, return FALSE);
+
+  /* The restart counter is not updated until we successfully write the MCU. */
+
+  return TRUE;
+}
+
+
+/*
+ * Encode and output nMCU MCUs' worth of Huffman-compressed differences.
+ */
+
+METHODDEF(JDIMENSION)
+encode_mcus_huff(j_compress_ptr cinfo, JDIFFIMAGE diff_buf,
+                 JDIMENSION MCU_row_num, JDIMENSION MCU_col_num,
+                 JDIMENSION nMCU)
+{
+  lhuff_entropy_ptr entropy = (lhuff_entropy_ptr)cinfo->entropy;
+  working_state state;
+  int sampn, ci, yoffset, MCU_width, ptrn;
+  JDIMENSION mcu_num;
+
+  /* Load up working state */
+  state.next_output_byte = cinfo->dest->next_output_byte;
+  state.free_in_buffer = cinfo->dest->free_in_buffer;
+  state.cur = entropy->saved;
+  state.cinfo = cinfo;
+
+  /* Emit restart marker if needed */
+  if (cinfo->restart_interval) {
+    if (entropy->restarts_to_go == 0)
+      if (!emit_restart(&state, entropy->next_restart_num))
+        return 0;
+  }
+
+  /* Set input pointer locations based on MCU_col_num */
+  for (ptrn = 0; ptrn < entropy->num_input_ptrs; ptrn++) {
+    ci = entropy->input_ptr_info[ptrn].ci;
+    yoffset = entropy->input_ptr_info[ptrn].yoffset;
+    MCU_width = entropy->input_ptr_info[ptrn].MCU_width;
+    entropy->input_ptr[ptrn] =
+      diff_buf[ci][MCU_row_num + yoffset] + (MCU_col_num * MCU_width);
+  }
+
+  for (mcu_num = 0; mcu_num < nMCU; mcu_num++) {
+
+    /* Inner loop handles the samples in the MCU */
+    for (sampn = 0; sampn < cinfo->blocks_in_MCU; sampn++) {
+      register int temp, temp2;
+      register int nbits;
+      c_derived_tbl *dctbl = entropy->cur_tbls[sampn];
+
+      /* Encode the difference per section H.1.2.2 */
+
+      /* Input the sample difference */
+      temp = *entropy->input_ptr[entropy->input_ptr_index[sampn]]++;
+
+      if (temp & 0x8000) {      /* instead of temp < 0 */
+        temp = (-temp) & 0x7FFF; /* absolute value, mod 2^16 */
+        if (temp == 0)          /* special case: magnitude = 32768 */
+          temp2 = temp = 0x8000;
+        temp2 = ~temp;          /* one's complement of magnitude */
+      } else {
+        temp &= 0x7FFF;         /* abs value mod 2^16 */
+        temp2 = temp;           /* magnitude */
+      }
+
+      /* Find the number of bits needed for the magnitude of the difference */
+      nbits = 0;
+      while (temp) {
+        nbits++;
+        temp >>= 1;
+      }
+      /* Check for out-of-range difference values.
+       */
+      if (nbits > MAX_DIFF_BITS)
+        ERREXIT(cinfo, JERR_BAD_DCT_COEF);
+
+      /* Emit the Huffman-coded symbol for the number of bits */
+      if (!emit_bits(&state, dctbl->ehufco[nbits], dctbl->ehufsi[nbits]))
+        return mcu_num;
+
+      /* 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 */
+          nbits != 16)          /* special case: no bits should be emitted */
+        if (!emit_bits(&state, (unsigned int)temp2, nbits))
+          return mcu_num;
+    }
+
+    /* Completed MCU, so update state */
+    cinfo->dest->next_output_byte = state.next_output_byte;
+    cinfo->dest->free_in_buffer = state.free_in_buffer;
+    entropy->saved = state.cur;
+
+    /* 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 nMCU;
+}
+
+
+/*
+ * Finish up at the end of a Huffman-compressed scan.
+ */
+
+METHODDEF(void)
+finish_pass_huff(j_compress_ptr cinfo)
+{
+  lhuff_entropy_ptr entropy = (lhuff_entropy_ptr)cinfo->entropy;
+  working_state state;
+
+  /* Load up working state ... flush_bits needs it */
+  state.next_output_byte = cinfo->dest->next_output_byte;
+  state.free_in_buffer = cinfo->dest->free_in_buffer;
+  state.cur = entropy->saved;
+  state.cinfo = cinfo;
+
+  /* Flush out the last data */
+  if (!flush_bits(&state))
+    ERREXIT(cinfo, JERR_CANT_SUSPEND);
+
+  /* Update state */
+  cinfo->dest->next_output_byte = state.next_output_byte;
+  cinfo->dest->free_in_buffer = state.free_in_buffer;
+  entropy->saved = state.cur;
+}
+
+
+/*
+ * Huffman coding optimization.
+ *
+ * We first scan the supplied data and count the number of uses of each symbol
+ * that is to be Huffman-coded. (This process MUST agree with the code above.)
+ * Then we build a Huffman coding tree for the observed counts.
+ * Symbols which are not needed at all for the particular image are not
+ * assigned any code, which saves space in the DHT marker as well as in
+ * the compressed data.
+ */
+
+#ifdef ENTROPY_OPT_SUPPORTED
+
+/*
+ * Trial-encode nMCU MCUs' worth of Huffman-compressed differences.
+ * No data is actually output, so no suspension return is possible.
+ */
+
+METHODDEF(JDIMENSION)
+encode_mcus_gather(j_compress_ptr cinfo, JDIFFIMAGE diff_buf,
+                   JDIMENSION MCU_row_num, JDIMENSION MCU_col_num,
+                   JDIMENSION nMCU)
+{
+  lhuff_entropy_ptr entropy = (lhuff_entropy_ptr)cinfo->entropy;
+  int sampn, ci, yoffset, MCU_width, ptrn;
+  JDIMENSION mcu_num;
+
+  /* Take care of restart intervals if needed */
+  if (cinfo->restart_interval) {
+    if (entropy->restarts_to_go == 0) {
+      /* Update restart state */
+      entropy->restarts_to_go = cinfo->restart_interval;
+    }
+    entropy->restarts_to_go--;
+  }
+
+  /* Set input pointer locations based on MCU_col_num */
+  for (ptrn = 0; ptrn < entropy->num_input_ptrs; ptrn++) {
+    ci = entropy->input_ptr_info[ptrn].ci;
+    yoffset = entropy->input_ptr_info[ptrn].yoffset;
+    MCU_width = entropy->input_ptr_info[ptrn].MCU_width;
+    entropy->input_ptr[ptrn] =
+      diff_buf[ci][MCU_row_num + yoffset] + (MCU_col_num * MCU_width);
+  }
+
+  for (mcu_num = 0; mcu_num < nMCU; mcu_num++) {
+
+    /* Inner loop handles the samples in the MCU */
+    for (sampn = 0; sampn < cinfo->blocks_in_MCU; sampn++) {
+      register int temp;
+      register int nbits;
+      long *counts = entropy->cur_counts[sampn];
+
+      /* Encode the difference per section H.1.2.2 */
+
+      /* Input the sample difference */
+      temp = *entropy->input_ptr[entropy->input_ptr_index[sampn]]++;
+
+      if (temp & 0x8000) {      /* instead of temp < 0 */
+        temp = (-temp) & 0x7FFF; /* absolute value, mod 2^16 */
+        if (temp == 0)          /* special case: magnitude = 32768 */
+          temp = 0x8000;
+      } else
+        temp &= 0x7FFF;         /* abs value mod 2^16 */
+
+      /* Find the number of bits needed for the magnitude of the difference */
+      nbits = 0;
+      while (temp) {
+        nbits++;
+        temp >>= 1;
+      }
+      /* Check for out-of-range difference values.
+       */
+      if (nbits > MAX_DIFF_BITS)
+        ERREXIT(cinfo, JERR_BAD_DCT_COEF);
+
+      /* Count the Huffman symbol for the number of bits */
+      counts[nbits]++;
+    }
+  }
+
+  return nMCU;
+}
+
+
+/*
+ * Finish up a statistics-gathering pass and create the new Huffman tables.
+ */
+
+METHODDEF(void)
+finish_pass_gather(j_compress_ptr cinfo)
+{
+  lhuff_entropy_ptr entropy = (lhuff_entropy_ptr)cinfo->entropy;
+  int ci, dctbl;
+  jpeg_component_info *compptr;
+  JHUFF_TBL **htblptr;
+  boolean did_dc[NUM_HUFF_TBLS];
+
+  /* It's important not to apply jpeg_gen_optimal_table more than once
+   * per table, because it clobbers the input frequency counts!
+   */
+  memset(did_dc, 0, sizeof(did_dc));
+
+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
+    compptr = cinfo->cur_comp_info[ci];
+    dctbl = compptr->dc_tbl_no;
+    if (!did_dc[dctbl]) {
+      htblptr = &cinfo->dc_huff_tbl_ptrs[dctbl];
+      if (*htblptr == NULL)
+        *htblptr = jpeg_alloc_huff_table((j_common_ptr)cinfo);
+      jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[dctbl]);
+      did_dc[dctbl] = TRUE;
+    }
+  }
+}
+
+
+#endif /* ENTROPY_OPT_SUPPORTED */
+
+
+/*
+ * Module initialization routine for Huffman entropy encoding.
+ */
+
+GLOBAL(void)
+jinit_lhuff_encoder(j_compress_ptr cinfo)
+{
+  lhuff_entropy_ptr entropy;
+  int i;
+
+  entropy = (lhuff_entropy_ptr)
+    (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+                                sizeof(lhuff_entropy_encoder));
+  cinfo->entropy = (struct jpeg_entropy_encoder *)entropy;
+  entropy->pub.start_pass = start_pass_lhuff;
+
+  /* Mark tables unallocated */
+  for (i = 0; i < NUM_HUFF_TBLS; i++) {
+    entropy->derived_tbls[i] = NULL;
+#ifdef ENTROPY_OPT_SUPPORTED
+    entropy->count_ptrs[i] = NULL;
+#endif
+  }
+}
+
+#endif /* C_LOSSLESS_SUPPORTED */