I solved this problem by creating a custom bitmap.xml file:
<?xml version="1.0" encoding="utf-8"?>
<bitmap
xmlns:android="http://schemas.android.com/apk/res/android"
android:src="@drawable/small"
android:antialias="false"
android:dither="false"
android:filter="false"
android:gravity="center"
android:mipMap="false"
android:tileMode="disabled" />
and placing it within a new folder @drawable-nodpi that I created in my res.
Then I referred to a manually-scaled image of the size I needed.