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diff --git a/gpr/source/lib/vc5_common/bitstream.h b/gpr/source/lib/vc5_common/bitstream.h
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+++ b/gpr/source/lib/vc5_common/bitstream.h
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+/*! @file bitstream.h
+ *
+ *  @brief Declaration of the bitstream data structure.
+ *
+ *  @version 1.0.0
+ *
+ *  (C) Copyright 2018 GoPro Inc (http://gopro.com/).
+ *
+ *  Licensed under either:
+ *  - Apache License, Version 2.0, http://www.apache.org/licenses/LICENSE-2.0
+ *  - MIT license, http://opensource.org/licenses/MIT
+ *  at your option.
+ *
+ *  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 BITSTREAM_H
+#define BITSTREAM_H
+
+/*!
+	@brief Bitstream error codes
+ 
+	The bitstream contains its own enumeration of error codes since this
+	module may be used in other applications.
+ */
+typedef enum _bitstream_error
+{
+    BITSTREAM_ERROR_OKAY = 0,		//!< No error
+    BITSTREAM_ERROR_UNDERFLOW,		//!< No unread bits remaining in the bitstream
+    BITSTREAM_ERROR_OVERFLOW,		//!< No more bits can be written to the bitstream
+    BITSTREAM_ERROR_BADTAG,			//!< Unexpected tag found in the bitstream
+    
+    //TODO: Add more bitstream errors
+    
+} BITSTREAM_ERROR;
+
+typedef uint32_t BITWORD;			//!< Data type of the internal bitstream buffer
+
+typedef uint_fast8_t BITCOUNT;		//!< Number of bits in the bitsteam buffer
+
+//! Maximum number of bits in a bit word
+static const BITCOUNT bit_word_count = 32;
+
+//! Maximum value of a bit word
+#define BIT_WORD_MAX 0xFFFFFFFF
+
+//! Sample offset stack depth
+#define MAX_SAMPLE_OFFSET_COUNT		8
+
+/*!
+	@brief Declaration of the bitstream data structure
+ 
+	The bitstream uses a byte stream to read bytes from a file or a buffer
+	in memory.  This isolates that bitstream module from the type of byte
+	stream.
+ */
+typedef struct _bitstream
+{
+    BITSTREAM_ERROR error;		//!< Error while processing the bitstream
+    struct _stream *stream;		//!< Stream for reading bytes into the buffer
+    BITWORD buffer;				//!< Internal buffer holds remaining bits
+    BITCOUNT count;				//!< Number of bits remaining in the buffer
+    
+#if VC5_ENABLED_PART(VC5_PART_SECTIONS)
+    /*!
+     The sample offset stack is used to record offsets to the start of nested
+     syntax structures.  For example, a sample size segment is written into the
+     bitstream with a size of zero, since the size of the syntax element is not
+     known in advance.  The offset to the sample size segment is pushed onto the
+     sample offset stack so that the location of the sample size segment can be
+     updated with the actual size of a syntax element after the complete element
+     is written into the bitstream.
+     
+     This data structure is called the ChunkSizeOffset in the current codec
+     implementation.
+     */
+    uint32_t sample_offset_stack[MAX_SAMPLE_OFFSET_COUNT];
+    
+    //! Number of entries in the sample offset stack
+    uint_fast8_t sample_offset_count;
+#endif
+    
+} BITSTREAM;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+    
+    BITWORD BitMask(int n);
+
+    CODEC_ERROR CodecErrorBitstream(BITSTREAM_ERROR error);
+
+    // Initialize a bitstream data structure
+    CODEC_ERROR InitBitstream(BITSTREAM *bitstream);
+
+    // Bind the bitstream to a byte stream
+    CODEC_ERROR AttachBitstream(struct _bitstream *bitstream, struct _stream *stream);
+
+    CODEC_ERROR ReleaseBitstream(BITSTREAM *stream);
+
+    BITWORD GetBits(BITSTREAM *stream, BITCOUNT count);
+
+    CODEC_ERROR PutBits(BITSTREAM *stream, BITWORD bits, BITCOUNT count);
+
+    BITWORD AddBits(BITSTREAM *stream, BITWORD bits, BITCOUNT count);
+
+    CODEC_ERROR GetBuffer(BITSTREAM *stream);
+
+    CODEC_ERROR PutBuffer(BITSTREAM *stream);
+
+    CODEC_ERROR PutLong(BITSTREAM *stream, BITWORD longword);
+
+    // Rewind the bitstream and the associated byte stream
+    CODEC_ERROR RewindBitstream(BITSTREAM *bitstream);
+
+    CODEC_ERROR BitstreamCodecError(BITSTREAM *bitstream);
+
+    // Return the current position of the bitstream pointer in the sample
+    size_t GetBitstreamPosition(BITSTREAM *stream);
+
+    CODEC_ERROR FlushBitstream(BITSTREAM *bitstream);
+
+    CODEC_ERROR GetByteArray(BITSTREAM *bitstream, uint8_t *array, size_t size);
+
+    CODEC_ERROR PutByteArray(BITSTREAM *bitstream, const uint8_t *block, size_t size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // BITSTREAM_H