File Manager

X7ROOT File Manager

Current Path: /opt/alt/tests/alt-php80-pecl-brotli_0.18.3-2.el8/brotli/c/enc

opt / alt / tests / alt-php80-pecl-brotli_0.18.3-2.el8 / brotli / c / enc /

?? ..
?? .libs
?? backward_references.c(6.13 KB)
?? backward_references.h(1.18 KB)
?? backward_references.lo(303 B)
?? backward_references_hq.c(35.88 KB)
?? backward_references_hq.h(3.68 KB)
?? backward_references_hq.lo(309 B)
?? backward_references_inc.h(7.99 KB)
?? bit_cost.c(1.39 KB)
?? bit_cost.h(896 B)
?? bit_cost.lo(281 B)
?? bit_cost_inc.h(4.02 KB)
?? block_encoder_inc.h(1.11 KB)
?? block_splitter.c(7.16 KB)
?? block_splitter.h(1.59 KB)
?? block_splitter.lo(293 B)
?? block_splitter_inc.h(18.44 KB)
?? brotli_bit_stream.c(49.72 KB)
?? brotli_bit_stream.h(3.26 KB)
?? brotli_bit_stream.lo(299 B)
?? cluster.c(1.42 KB)
?? cluster.h(997 B)
?? cluster.lo(279 B)
?? cluster_inc.h(11.55 KB)
?? command.c(1 KB)
?? command.h(6.77 KB)
?? command.lo(279 B)
?? compound_dictionary.c(6.5 KB)
?? compound_dictionary.h(2.38 KB)
?? compound_dictionary.lo(303 B)
?? compress_fragment.c(32.1 KB)
?? compress_fragment.h(3.49 KB)
?? compress_fragment.lo(299 B)
?? compress_fragment_two_pass.c(26.18 KB)
?? compress_fragment_two_pass.h(2.79 KB)
?? compress_fragment_two_pass.lo(317 B)
?? dictionary_hash.c(7.75 KB)
?? dictionary_hash.h(1.5 KB)
?? dictionary_hash.lo(295 B)
?? dictionary_hash_inc.h(143.28 KB)
?? encode.c(76.58 KB)
?? encode.lo(277 B)
?? encoder_dict.c(22.83 KB)
?? encoder_dict.h(4.9 KB)
?? encoder_dict.lo(289 B)
?? entropy_encode.c(14.23 KB)
?? entropy_encode.h(3.96 KB)
?? entropy_encode.lo(293 B)
?? entropy_encode_static.h(32.37 KB)
?? fast_log.c(5.9 KB)
?? fast_log.h(1.61 KB)
?? fast_log.lo(281 B)
?? find_match_length.h(2.12 KB)
?? hash.h(23.73 KB)
?? hash_base.h(1.34 KB)
?? hash_composite_inc.h(4.98 KB)
?? hash_forgetful_chain_inc.h(11.05 KB)
?? hash_longest_match64_inc.h(10.41 KB)
?? hash_longest_match64_simd_inc.h(11.56 KB)
?? hash_longest_match_inc.h(10.34 KB)
?? hash_longest_match_quickly_inc.h(9.26 KB)
?? hash_longest_match_simd_inc.h(11.48 KB)
?? hash_rolling_inc.h(7.06 KB)
?? hash_to_binary_tree_inc.h(12.77 KB)
?? histogram.c(3.18 KB)
?? histogram.h(1.77 KB)
?? histogram.lo(283 B)
?? histogram_inc.h(1.37 KB)
?? literal_cost.c(5.74 KB)
?? literal_cost.h(889 B)
?? literal_cost.lo(289 B)
?? matching_tag_mask.h(2.29 KB)
?? memory.c(5.39 KB)
?? memory.h(4.2 KB)
?? memory.lo(277 B)
?? metablock.c(26.07 KB)
?? metablock.h(3.93 KB)
?? metablock.lo(283 B)
?? metablock_inc.h(7.46 KB)
?? params.h(1.14 KB)
?? prefix.h(1.9 KB)
?? quality.h(7.68 KB)
?? ringbuffer.h(5.83 KB)
?? state.h(3.01 KB)
?? static_dict.c(20.39 KB)
?? static_dict.h(1.19 KB)
?? static_dict.lo(287 B)
?? static_dict_lut.c(7.25 KB)
?? static_dict_lut.h(1.55 KB)
?? static_dict_lut.lo(295 B)
?? static_dict_lut_inc.h(457.82 KB)
?? static_init.c(1.74 KB)
?? static_init.h(840 B)
?? static_init.lo(287 B)
?? utf8_util.c(2.22 KB)
?? utf8_util.h(878 B)
?? utf8_util.lo(283 B)
?? write_bits.h(2.77 KB)

Editing: literal_cost.c

Distributed under MIT license.
   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/

/* Literal cost model to allow backward reference replacement to be efficient.
*/

#include "literal_cost.h"

#include "../common/platform.h"
#include "fast_log.h"
#include "utf8_util.h"

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

static size_t UTF8Position(size_t last, size_t c, size_t clamp) {
  if (c < 128) {
    return 0;  /* Next one is the 'Byte 1' again. */
  } else if (c >= 192) {  /* Next one is the 'Byte 2' of utf-8 encoding. */
    return BROTLI_MIN(size_t, 1, clamp);
  } else {
    /* Let's decide over the last byte if this ends the sequence. */
    if (last < 0xE0) {
      return 0;  /* Completed two or three byte coding. */
    } else {  /* Next one is the 'Byte 3' of utf-8 encoding. */
      return BROTLI_MIN(size_t, 2, clamp);
    }
  }
}

static size_t DecideMultiByteStatsLevel(size_t pos, size_t len, size_t mask,
                                        const uint8_t* data) {
  size_t counts[3] = { 0 };
  size_t max_utf8 = 1;  /* should be 2, but 1 compresses better. */
  size_t last_c = 0;
  size_t i;
  for (i = 0; i < len; ++i) {
    size_t c = data[(pos + i) & mask];
    ++counts[UTF8Position(last_c, c, 2)];
    last_c = c;
  }
  if (counts[2] < 500) {
    max_utf8 = 1;
  }
  if (counts[1] + counts[2] < 25) {
    max_utf8 = 0;
  }
  return max_utf8;
}

static void EstimateBitCostsForLiteralsUTF8(size_t pos, size_t len, size_t mask,
                                            const uint8_t* data,
                                            size_t* histogram, float* cost) {
  /* max_utf8 is 0 (normal ASCII single byte modeling),
     1 (for 2-byte UTF-8 modeling), or 2 (for 3-byte UTF-8 modeling). */
  const size_t max_utf8 = DecideMultiByteStatsLevel(pos, len, mask, data);
  size_t window_half = 495;
  size_t in_window = BROTLI_MIN(size_t, window_half, len);
  size_t in_window_utf8[3] = { 0 };
  size_t i;
  memset(histogram, 0, 3 * 256 * sizeof(histogram[0]));

{  /* Bootstrap histograms. */
    size_t last_c = 0;
    size_t utf8_pos = 0;
    for (i = 0; i < in_window; ++i) {
      size_t c = data[(pos + i) & mask];
      ++histogram[256 * utf8_pos + c];
      ++in_window_utf8[utf8_pos];
      utf8_pos = UTF8Position(last_c, c, max_utf8);
      last_c = c;
    }
  }

/* Compute bit costs with sliding window. */
  for (i = 0; i < len; ++i) {
    if (i >= window_half) {
      /* Remove a byte in the past. */
      size_t c =
          i < window_half + 1 ? 0 : data[(pos + i - window_half - 1) & mask];
      size_t last_c =
          i < window_half + 2 ? 0 : data[(pos + i - window_half - 2) & mask];
      size_t utf8_pos2 = UTF8Position(last_c, c, max_utf8);
      --histogram[256 * utf8_pos2 + data[(pos + i - window_half) & mask]];
      --in_window_utf8[utf8_pos2];
    }
    if (i + window_half < len) {
      /* Add a byte in the future. */
      size_t c = data[(pos + i + window_half - 1) & mask];
      size_t last_c = data[(pos + i + window_half - 2) & mask];
      size_t utf8_pos2 = UTF8Position(last_c, c, max_utf8);
      ++histogram[256 * utf8_pos2 + data[(pos + i + window_half) & mask]];
      ++in_window_utf8[utf8_pos2];
    }
    {
      size_t c = i < 1 ? 0 : data[(pos + i - 1) & mask];
      size_t last_c = i < 2 ? 0 : data[(pos + i - 2) & mask];
      size_t utf8_pos = UTF8Position(last_c, c, max_utf8);
      size_t masked_pos = (pos + i) & mask;
      size_t histo = histogram[256 * utf8_pos + data[masked_pos]];
      static const size_t prologue_length = 2000;
      static const double multiplier = 0.35 / 2000;
      double lit_cost;
      if (histo == 0) {
        histo = 1;
      }
      lit_cost = FastLog2(in_window_utf8[utf8_pos]) - FastLog2(histo);
      lit_cost += 0.02905;
      if (lit_cost < 1.0) {
        lit_cost *= 0.5;
        lit_cost += 0.5;
      }
      /* Make the first bytes more expensive -- seems to help, not sure why.
         Perhaps because the entropy source is changing its properties
         rapidly in the beginning of the file, perhaps because the beginning
         of the data is a statistical "anomaly". */
      if (i < prologue_length) {
        lit_cost += 0.35 + multiplier * (double)i;
      }
      cost[i] = (float)lit_cost;
    }
  }
}

void BrotliEstimateBitCostsForLiterals(size_t pos, size_t len, size_t mask,
                                       const uint8_t* data,
                                       size_t* histogram, float* cost) {
  if (BrotliIsMostlyUTF8(data, pos, mask, len, kMinUTF8Ratio)) {
    EstimateBitCostsForLiteralsUTF8(pos, len, mask, data, histogram, cost);
    return;
  } else {
    size_t window_half = 2000;
    size_t in_window = BROTLI_MIN(size_t, window_half, len);
    size_t i;
    memset(histogram, 0, 256 * sizeof(histogram[0]));

/* Bootstrap histogram. */
    for (i = 0; i < in_window; ++i) {
      ++histogram[data[(pos + i) & mask]];
    }

/* Compute bit costs with sliding window. */
    for (i = 0; i < len; ++i) {
      size_t histo;
      if (i >= window_half) {
        /* Remove a byte in the past. */
        --histogram[data[(pos + i - window_half) & mask]];
        --in_window;
      }
      if (i + window_half < len) {
        /* Add a byte in the future. */
        ++histogram[data[(pos + i + window_half) & mask]];
        ++in_window;
      }
      histo = histogram[data[(pos + i) & mask]];
      if (histo == 0) {
        histo = 1;
      }
      {
        double lit_cost = FastLog2(in_window) - FastLog2(histo);
        lit_cost += 0.029;
        if (lit_cost < 1.0) {
          lit_cost *= 0.5;
          lit_cost += 0.5;
        }
        cost[i] = (float)lit_cost;
      }
    }
  }
}

#if defined(__cplusplus) || defined(c_plusplus)
}  /* extern "C" */
#endif

X7ROOT File Manager

Editing: literal_cost.c

Upload File

Create Folder