diff --git a/C/src/bit_allocation.c b/C/src/bit_allocation.c
index 33d8f4f..bff5966 100644
--- a/C/src/bit_allocation.c
+++ b/C/src/bit_allocation.c
@@ -123,7 +123,7 @@ void CalculatePrecisions(Channel* channel)
 static const unsigned char BaseCurve[48] =
 {
 	1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 6, 7, 8, 9, 10, 11, 12, 13,
-	15, 6, 18, 19, 20, 21, 22, 23, 24, 25, 26, 26, 27, 27, 28, 28, 28, 29, 29,
+	15, 16, 18, 19, 20, 21, 22, 23, 24, 25, 26, 26, 27, 27, 28, 28, 28, 29, 29,
 	29, 29, 30, 30, 30, 30
 };
 
diff --git a/C/src/unpack.c b/C/src/unpack.c
index 6e3f4f8..e2cbf61 100644
--- a/C/src/unpack.c
+++ b/C/src/unpack.c
@@ -169,11 +169,11 @@ static At9Status ReadGradientParams(Block* block, BitReaderCxt* br)
 	{
 		return ERR_UNPACK_GRAD_BOUNDARY_INVALID;
 	}
-	if (block->GradientStartUnit < 1 || block->GradientStartUnit >= 48)
+	if (block->GradientStartUnit < 0 || block->GradientStartUnit >= 48)
 	{
 		return ERR_UNPACK_GRAD_START_UNIT_OOB;
 	}
-	if (block->GradientEndUnit < 1 || block->GradientEndUnit >= 48)
+	if (block->GradientEndUnit < 0 || block->GradientEndUnit >= 48)
 	{
 		return ERR_UNPACK_GRAD_END_UNIT_OOB;
 	}