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diff --git a/gpr/source/lib/vc5_encoder/vlc.c b/gpr/source/lib/vc5_encoder/vlc.c
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+/*! @file vlc.c
+ *
+ *  @brief Implementation of routines to insert variable length codes into the bitstream
+ *
+ *  @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.
+ */
+
+#include "headers.h"
+
+/*!
+	@brief Write the codewords for a run of zeros into the bitstream
+
+	The codebook contains codewords for a few runs of zeros.  This routine writes
+	multiple codewords into the bitstream until the specified number of zeros has
+	been written into the bitstream.
+*/
+CODEC_ERROR PutZeros(BITSTREAM *stream, const RUNS_TABLE *runs_table, uint32_t count)
+{
+	// Get the length of the codebook and a pointer to the entries
+	uint32_t length = runs_table->length;
+	RLC *rlc = (RLC *)((uint8_t *)runs_table + sizeof(RUNS_TABLE));
+	int index;
+
+	// Output one or more run lengths until the run is finished
+	while (count > 0)
+	{
+		// Index into the codebook to get a run length code that covers most of the run
+		index = (count < length) ? count : length - 1;
+
+		// Output the run length code
+		PutBits(stream, rlc[index].bits, rlc[index].size);
+
+		// Reduce the length of the run by the amount output
+		count -= rlc[index].count;
+	}
+
+	// Should have output enough runs to cover the run of zeros
+	assert(count == 0);
+
+	return CODEC_ERROR_OKAY;
+}
+
+/*!
+	@brief Insert a special codeword into the bitstream
+
+	The codebook contains special codewords in addition to the codebook
+	entries for coefficient magnitudes and runs of zeros.  Special codewords
+	are used to mark important locations in the bitstream.  Currently,
+	the only special codeword is the one that marks the end of an encoded
+	band.
+*/
+CODEC_ERROR PutSpecial(BITSTREAM *stream, const CODEBOOK *codebook, SPECIAL_MARKER marker)
+{
+	int codebook_length = codebook->length;
+	RLV *codebook_entry = (RLV *)((uint8_t *)codebook + sizeof(CODEBOOK));
+
+	int index;
+
+	// Find the special code that corresponds to the marker
+	for (index = 0; index < codebook_length; index++)
+	{
+		// Is this entry a special code?
+		if (codebook_entry[index].count != 0) {
+			continue;
+		}
+		
+		// Is this entry the special code for the marker?
+		if (codebook_entry[index].value == (int32_t)marker) {
+			break;
+		}
+	}
+	assert(index < codebook_length);
+	if (! (index < codebook_length)) {
+		// Did not find the special code for the marker in the codebook
+		return CODEC_ERROR_INVALID_MARKER;
+	}
+
+	PutBits(stream, codebook_entry[index].bits, codebook_entry[index].size);
+
+	return CODEC_ERROR_OKAY;
+}