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diff --git a/modules/brotli/dec/huffman.h b/modules/brotli/dec/huffman.h
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+++ b/modules/brotli/dec/huffman.h
@@ -0,0 +1,68 @@
+/* Copyright 2013 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+/* Utilities for building Huffman decoding tables. */
+
+#ifndef BROTLI_DEC_HUFFMAN_H_
+#define BROTLI_DEC_HUFFMAN_H_
+
+#include "./types.h"
+#include "./port.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#define BROTLI_HUFFMAN_MAX_CODE_LENGTH 15
+
+/* For current format this constant equals to kNumInsertAndCopyCodes */
+#define BROTLI_HUFFMAN_MAX_CODE_LENGTHS_SIZE 704
+
+/* Maximum possible Huffman table size for an alphabet size of (index * 32),
+ * max code length 15 and root table bits 8. */
+static const uint16_t kMaxHuffmanTableSize[] = {
+  256, 402, 436, 468, 500, 534, 566, 598, 630, 662, 694, 726, 758, 790, 822,
+  854, 886, 920, 952, 984, 1016, 1048, 1080};
+#define BROTLI_HUFFMAN_MAX_SIZE_26 396
+#define BROTLI_HUFFMAN_MAX_SIZE_258 632
+#define BROTLI_HUFFMAN_MAX_SIZE_272 646
+
+#define BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH 5
+
+typedef struct {
+  uint8_t bits;    /* number of bits used for this symbol */
+  uint16_t value;  /* symbol value or table offset */
+} HuffmanCode;
+
+/* Builds Huffman lookup table assuming code lengths are in symbol order. */
+BROTLI_INTERNAL void BrotliBuildCodeLengthsHuffmanTable(HuffmanCode* root_table,
+    const uint8_t* const code_lengths, uint16_t* count);
+
+/* Builds Huffman lookup table assuming code lengths are in symbol order. */
+/* Returns size of resulting table. */
+BROTLI_INTERNAL uint32_t BrotliBuildHuffmanTable(HuffmanCode* root_table,
+    int root_bits, const uint16_t* const symbol_lists, uint16_t* count_arg);
+
+/* Builds a simple Huffman table. The num_symbols parameter is to be */
+/* interpreted as follows: 0 means 1 symbol, 1 means 2 symbols, 2 means 3 */
+/* symbols, 3 means 4 symbols with lengths 2,2,2,2, 4 means 4 symbols with */
+/* lengths 1,2,3,3. */
+BROTLI_INTERNAL uint32_t BrotliBuildSimpleHuffmanTable(HuffmanCode* table,
+    int root_bits, uint16_t* symbols, uint32_t num_symbols);
+
+/* Contains a collection of Huffman trees with the same alphabet size. */
+typedef struct {
+  HuffmanCode** htrees;
+  HuffmanCode* codes;
+  uint16_t alphabet_size;
+  uint16_t num_htrees;
+} HuffmanTreeGroup;
+
+#if defined(__cplusplus) || defined(c_plusplus)
+}  /* extern "C" */
+#endif
+
+#endif  /* BROTLI_DEC_HUFFMAN_H_ */