diff --git a/src/bin/jp2/opj_decompress.c b/src/bin/jp2/opj_decompress.c
index 8ac2d9c7..b5a7db2c 100644
--- a/src/bin/jp2/opj_decompress.c
+++ b/src/bin/jp2/opj_decompress.c
@@ -1341,7 +1341,7 @@ int main(int argc, char **argv)
 {
     opj_decompress_parameters parameters;           /* decompression parameters */
 
-    OPJ_INT32 num_images, imageno;
+    unsigned int num_images, imageno;
     img_fol_t img_fol;
     dircnt_t *dirptr = NULL;
     int failed = 0;
diff --git a/src/bin/jp2/opj_dump.c b/src/bin/jp2/opj_dump.c
index b297fefd..a1252b5e 100644
--- a/src/bin/jp2/opj_dump.c
+++ b/src/bin/jp2/opj_dump.c
@@ -492,7 +492,7 @@ int main(int argc, char *argv[])
     opj_codestream_info_v2_t* cstr_info = NULL;
     opj_codestream_index_t* cstr_index = NULL;
 
-    OPJ_INT32 num_images, imageno;
+    unsigned int num_images, imageno;
     img_fol_t img_fol;
     dircnt_t *dirptr = NULL;