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diff --git a/gpr/source/lib/vc5_decoder/dequantize.c b/gpr/source/lib/vc5_decoder/dequantize.c
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+/*! @file dequantize.c
+ *
+ *  @brief Implementation of inverse quantization functions
+ *
+ *  @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"
+
+// Not using midpoint correction in dequantization
+static const int midpoint = 0;
+
+/*!
+	@brief Dequantize a band with the specified dimensions
+
+	The companding curve is inverted and the value is multiplied by the
+	quantization value that was used by the encoder to compress the band.
+*/
+CODEC_ERROR DequantizeBandRow16s(PIXEL *input, int width, int quantization, PIXEL *output)
+{
+	int column;
+
+	// Undo quantization in the entire row
+	for (column = 0; column < width; column++)
+	{
+		int32_t value = input[column];
+
+		// Invert the companding curve (if any)
+		value = UncompandedValue(value);
+
+		// Dequantize the absolute value
+		if (value > 0)
+		{
+			value = (quantization * value) + midpoint;
+		}
+		else if (value < 0)
+		{
+			value = neg(value);
+			value = (quantization * value) + midpoint;
+			value = neg(value);
+		}
+
+		// Store the dequantized coefficient
+		output[column] = ClampPixel(value);
+	}
+
+	return CODEC_ERROR_OKAY;
+}
+
+/*!
+	@brief This function dequantizes the pixel value
+
+	The inverse companding curve is applied to convert the pixel value
+	to its quantized value and then the pixel value is multiplied by
+	the quantization parameter.
+*/
+PIXEL DequantizedValue(int32_t value, int quantization)
+{
+	// Invert the companding curve (if any)
+	value = UncompandedValue(value);
+
+	// Dequantize the absolute value
+	if (value > 0)
+	{
+		value = (quantization * value) + midpoint;
+	}
+	else if (value < 0)
+	{
+		value = neg(value);
+		value = (quantization * value) + midpoint;
+		value = neg(value);
+	}
+
+	return ClampPixel(value);
+}