sound envelope catch no data

1 files changed, 14 insertions, 11 deletions

diff --git a/rotord/src/rotor.h b/rotord/src/rotor.h
index be6ecee..b95a7b0 100644
--- a/rotord/src/rotor.h
+++ b/rotord/src/rotor.h
@@ -983,17 +983,20 @@ namespace Rotor {
 			};
 			~Video_output(){ };
 			void create_envelope(const vector<float> &audio){
-				int i=0;
-				while (i<audio.size()&&audio[i]<silence_threshold) i++;
-				start_silence=((float)i)/audio.size();
-				while (i<audio.size()&&audio[i]>audio[i-1]) i++;
-				start_peak=((float)i-1)/audio.size();
-				i=audio.size();
-				while (i>-1&&audio[i]<silence_threshold) i--;
-				end_silence=((float)i)/audio.size();
-				while (i<audio.size()&&audio[i]>audio[i+1]) i--;
-				end_peak=((float)i+1)/audio.size();
-				cerr<<"Video_output sound envelope: silence - "<<start_silence<<" : peak "<<start_peak<<" : peak "<<end_peak<<" silence - "<<end_silence<<endl;
+				if (audio.size()){
+					int i=0;
+					while (i<audio.size()&&audio[i]<silence_threshold) i++;
+					start_silence=((float)i)/audio.size();
+					while (i<audio.size()&&audio[i]>audio[i-1]) i++;
+					start_peak=((float)i-1)/audio.size();
+					i=audio.size();
+					while (i>-1&&audio[i]<silence_threshold) i--;
+					end_silence=((float)i)/audio.size();
+					while (i<audio.size()&&audio[i]>audio[i+1]) i--;
+					end_peak=((float)i+1)/audio.size();
+					cerr<<"Video_output sound envelope: silence - "<<start_silence<<" : peak "<<start_peak<<" : peak "<<end_peak<<" silence - "<<end_silence<<endl;
+				}
+				else cerr<<"Video_output sound envelope: no data"<<endl;
 			}
 			Image *output(const Frame_spec &frame){
 				Image *in=image_inputs[0]->get(frame);