Change test video size to 1080p

Change-Id: I428f520a7018bd80cfc1cb7ac12864770168eb46
diff --git a/test/motion_vector_test.cc b/test/motion_vector_test.cc
index fe20fd1..5803806 100644
--- a/test/motion_vector_test.cc
+++ b/test/motion_vector_test.cc
@@ -81,7 +81,7 @@
 
   // Reduce the test clip's resolution while testing on 32-bit system.
   if (sizeof(void *) == 4) {
-    width = 2048;
+    width = 1920;
     height = 1080;
   }