Update readme with new pipe

Signed-off-by: Jael Gu <mengjia.gu@zilliz.com>

README.md

@@ -17,25 +17,26 @@ The nnfp operator is suitable for audio fingerprinting.
 
 ## Code Example
 
-Generate embeddings for the audio "test.wav". 
+Generate embeddings for the audio "test.wav".
 
-*Write the pipeline in simplified style*:
+*Write a same pipeline with explicit inputs/outputs name specifications:*
 
+- option 1 (towhee>=0.9.0):
 ```python
-import towhee
+from towhee.dc2 import pipe, ops, DataCollection
 
-(
-    towhee.glob('test.wav')
-          .audio_decode.ffmpeg()
-          .runas_op(func=lambda x:[y[0] for y in x])
-          .audio_embedding.nnfp()  # use default model
-          .show()
+p = (
+    pipe.input('path')
+        .map('path', 'frame', ops.audio_decode.ffmpeg())
+        .map('frame', 'vecs', ops.audio_embedding.nnfp(device='cpu'))
+        .output('path', 'vecs')
 )
-```
-<img src="./result1.png" width="800px"/>
 
-*Write a same pipeline with explicit inputs/outputs name specifications:*
+DataCollection(p('test.wav')).show()
+```
+<img src="./result.png" width="800px"/>
 
+- option 2:
 ```python
 import towhee
 
@@ -48,8 +49,6 @@ import towhee
           .show()
 )
 ```
-<img src="./result2.png" width="800px"/>
-
 <br />
 
 ## Factory Constructor