better volume terminology

include/mediastreamer2/msvolume.h

@@ -70,7 +70,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #define MS_VOLUME_SET_EA_TRANSMIT_THRESHOLD	MS_FILTER_METHOD(MS_VOLUME_ID,17,float)
 
 
-#define MS_VOLUME_MIN_ENERGY_DB		(-120)	/*arbitrary value returned when linear energy is 0*/
+#define MS_VOLUME_DB_LOWEST		(-120)	/*arbitrary value returned when linear volume is 0*/
 
 extern MSFilterDesc ms_volume_desc;
 

src/msvolume.c

@@ -116,7 +116,7 @@ static void volume_uninit(MSFilter *f){
 }
 
 static inline float linear_to_db(float linear){
-	if (linear==0) return MS_VOLUME_MIN_ENERGY_DB;
+	if (linear==0) return MS_VOLUME_DB_LOWEST;
 	return 10*ortp_log10f(linear);
 }