diff --git a/perceive_raw_tf.m b/perceive_raw_tf.m
index 8a1b98d..4f4cf59 100644
--- a/perceive_raw_tf.m
+++ b/perceive_raw_tf.m
@@ -1,6 +1,6 @@
 function [tf,t,f]=perceive_raw_tf(data,fs,timewindow,timestep)
 
-nfft = round(timewindow/fs*1000);
+nfft = min(round(timewindow/fs*1000), length(data));
 timestep = round(timestep/fs*1000);
 [~,f,t,tf]=spectrogram(data,hann(nfft), ...
     nfft-timestep,nfft,fs,'yaxis','power');