noise: add help

diff --git a/noise b/noise
index 022754d8d151766396b107e9df15cf4ea7a2cea7..718003a7622a8c3d86706a7f5b6c02fd0b2c0030 100755 (executable)
--- a/noise
+++ b/noise
@@ -4,6 +4,14 @@
 
 DEFAULT_GAIN="26"
 
+
+if [ "$1" = "-h" ]; then
+    echo "Generate 1/f2 noise"
+    echo "Usage: $(basename $0) [gain]"
+    echo "    gain - in dB (default: $DEFAULT_GAIN)"
+    exit
+fi
+
 GAIN=${1:-$DEFAULT_GAIN}
 
 echo "gain: ${GAIN}"