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diff --git a/src/utils/raw_bit_reader.h b/src/utils/raw_bit_reader.h
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+/*
+ * Copyright 2019 The libgav1 Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef LIBGAV1_SRC_UTILS_RAW_BIT_READER_H_
+#define LIBGAV1_SRC_UTILS_RAW_BIT_READER_H_
+
+#include <cstddef>
+#include <cstdint>
+
+#include "src/utils/bit_reader.h"
+#include "src/utils/memory.h"
+
+namespace libgav1 {
+
+class RawBitReader : public BitReader, public Allocable {
+ public:
+  RawBitReader(const uint8_t* data, size_t size);
+  ~RawBitReader() override = default;
+
+  int ReadBit() override;
+  int64_t ReadLiteral(int num_bits) override;  // f(n) in the spec.
+  bool ReadInverseSignedLiteral(int num_bits,
+                                int* value);  // su(1+num_bits) in the spec.
+  bool ReadLittleEndian(int num_bytes,
+                        size_t* value);    // le(n) in the spec.
+  bool ReadUnsignedLeb128(size_t* value);  // leb128() in the spec.
+  // Reads a variable length unsigned number and stores it in |*value|. On a
+  // successful return, |*value| is in the range of 0 to UINT32_MAX − 1,
+  // inclusive.
+  bool ReadUvlc(uint32_t* value);  // uvlc() in the spec.
+  bool Finished() const;
+  size_t bit_offset() const { return bit_offset_; }
+  // Return the bytes consumed so far (rounded up).
+  size_t byte_offset() const { return (bit_offset() + 7) >> 3; }
+  size_t size() const { return size_; }
+  // Move to the next byte boundary if not already at one. Return false if any
+  // of the bits being skipped over is non-zero. Return true otherwise. If this
+  // function returns false, the reader is left in an undefined state and must
+  // not be used further. section 5.3.5.
+  bool AlignToNextByte();
+  // Make sure that the trailing bits structure is as expected and skip over it.
+  // section 5.3.4.
+  bool VerifyAndSkipTrailingBits(size_t num_bits);
+  // Skip |num_bytes| bytes. This only works if the current position is at a
+  // byte boundary. The function returns false if the current position is not at
+  // a byte boundary or if skipping |num_bytes| causes the reader to run out of
+  // buffer. Returns true otherwise.
+  bool SkipBytes(size_t num_bytes);
+  // Skip |num_bits| bits. The function returns false if skipping |num_bits|
+  // causes the reader to run out of buffer. Returns true otherwise.
+  bool SkipBits(size_t num_bits);
+
+ private:
+  // Returns true if it is safe to read a literal of size |num_bits|.
+  bool CanReadLiteral(size_t num_bits) const;
+  int ReadBitImpl();
+
+  const uint8_t* const data_;
+  size_t bit_offset_;
+  const size_t size_;
+};
+
+}  // namespace libgav1
+
+#endif  // LIBGAV1_SRC_UTILS_RAW_BIT_READER_H_