+
+double
+db_to_linear (double db)
+{
+ return pow(10, db / 20);
+}
+
+double
+linear_to_db (double linear)
+{
+ return 20 * log10(linear);
+}
+
+
+dcp::Size
+scale_for_display (dcp::Size s, dcp::Size display_container, dcp::Size film_container)
+{
+ /* Now scale it down if the display container is smaller than the film container */
+ if (display_container != film_container) {
+ float const scale = min (
+ float (display_container.width) / film_container.width,
+ float (display_container.height) / film_container.height
+ );
+
+ s.width = lrintf (s.width * scale);
+ s.height = lrintf (s.height * scale);
+ }
+
+ return s;
+}
+