diff --git a/src/lib/openjp2/invert.c b/src/lib/openjp2/invert.c
index 5e2d6614..92de0a85 100644
--- a/src/lib/openjp2/invert.c
+++ b/src/lib/openjp2/invert.c
@@ -67,8 +67,8 @@ OPJ_BOOL opj_matrix_inversion_f(OPJ_FLOAT32 * pSrcMatrix,
                                 OPJ_UINT32 nb_compo)
 {
 	OPJ_BYTE * l_data = 00;
-	OPJ_UINT32 l_permutation_size = nb_compo * sizeof(OPJ_UINT32);
-	OPJ_UINT32 l_swap_size = nb_compo * sizeof(OPJ_FLOAT32);
+	OPJ_UINT32 l_permutation_size = nb_compo * (OPJ_UINT32)sizeof(OPJ_UINT32);
+	OPJ_UINT32 l_swap_size = nb_compo * (OPJ_UINT32)sizeof(OPJ_FLOAT32);
 	OPJ_UINT32 l_total_size = l_permutation_size + 3 * l_swap_size;
 	OPJ_UINT32 * lPermutations = 00;
 	OPJ_FLOAT32 * l_double_data = 00;
@@ -109,7 +109,7 @@ OPJ_BOOL opj_lupDecompose(OPJ_FLOAT32 * matrix,OPJ_UINT32 * permutations,
 	OPJ_UINT32 i,j,k;
 	OPJ_FLOAT32 p;
 	OPJ_UINT32 lLastColum = nb_compo - 1;
-	OPJ_UINT32 lSwapSize = nb_compo * sizeof(OPJ_FLOAT32);
+	OPJ_UINT32 lSwapSize = nb_compo * (OPJ_UINT32)sizeof(OPJ_FLOAT32);
 	OPJ_FLOAT32 * lTmpMatrix = matrix;
 	OPJ_FLOAT32 * lColumnMatrix,* lDestMatrix;
 	OPJ_UINT32 offset = 1;
@@ -272,7 +272,7 @@ void opj_lupInvert (OPJ_FLOAT32 * pSrcMatrix,
 	OPJ_UINT32 j,i;
 	OPJ_FLOAT32 * lCurrentPtr;
 	OPJ_FLOAT32 * lLineMatrix = pDestMatrix;
-	OPJ_UINT32 lSwapSize = nb_compo * sizeof(OPJ_FLOAT32);
+	OPJ_UINT32 lSwapSize = nb_compo * (OPJ_UINT32)sizeof(OPJ_FLOAT32);
 
 	for (j = 0; j < nb_compo; ++j) {
 		lCurrentPtr = lLineMatrix++;