I tried to use a background (480x320) for my tab content. Using a xml as drawable, I should be able to scale the image. This works fine outside the tabhost/tabactivity. If I
set the background to ur tabhost tag not in tabcontent layout. that is
<TabHost android:background="@drawable/background">
Try just placing this inside the RelativeLayout and not using your background drawable:
<Drawable
android:src="@drawable/background_img"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:scaleType="fitCenter" />
Since elements inside the relativelayout can overlap, this oughta work, and using a Drawable in the layout independently instead of a Bitmap included as the element background_src might give you more flexibility.