diff --git a/tests/tiny_psnr.c b/tests/tiny_psnr.c
index be129fa2d5764faafe4028e2d0fc8fa1b8b567e6..996f0404964cb2927f16046e7e5c8903d74ecbd7 100644
--- a/tests/tiny_psnr.c
+++ b/tests/tiny_psnr.c
@@ -106,8 +106,8 @@ int main(int argc,char* argv[]){
         return -1;
     }
     
-    f[0]= fopen(argv[1], "r");
-    f[1]= fopen(argv[2], "r");
+    f[0]= fopen(argv[1], "rb");
+    f[1]= fopen(argv[2], "rb");
 
     for(i=0;;){
         if( fread(buf[0], SIZE, 1, f[0]) != 1) break;