diff --git a/README.md b/README.md
index 19426bd..86d64cb 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ The pipeline uses a pre-trained CLMR model to extract embeddings of a given audi
 **Input Arguments:**
 
 - filepath:
-  - the input audio
+  - the input audio in `.wav`
   - supported types: `str` (path to the audio)
 
 **Pipeline Output:**
@@ -45,4 +45,3 @@ $ pip3 install towhee
 ## How it works
 
 This pipeline includes a main operator: [audio embedding](https://hub.towhee.io/towhee/audio-embedding-operator-template) (implemented as [towhee/clmr-magnatagatune](https://hub.towhee.io/towhee/clmr-magnatagatune)). The audio embedding operator encodes fixed-length clips of an audio data and finally output a set of vectors of the given audio.
-