update the readme.

Signed-off-by: wxywb <xy.wang@zilliz.com>

README.md

@@ -21,39 +21,29 @@ Load an image from path './teddy.jpg' to generate an image embedding.
 
 Read the text 'A teddybear on a skateboard in Times Square.' to generate an text embedding. 
 
- *Write the pipeline in simplified style*:
+*Write a pipeline with explicit inputs/outputs name specifications:*
 
 ```python
-import towhee
 
-towhee.glob('./teddy.jpg') \
-      .image_decode() \
-      .image_text_embedding.lightningdot(model_name='lightningdot_base', modality='image') \
-      .show()
+from towhee.dc2 import pipe, ops, DataCollection
 
-towhee.dc(["A teddybear on a skateboard in Times Square."]) \
-      .image_text_embedding.lightningdot(model_name='lightningdot_base', modality='text') \
-      .show()
-```
-<img src="https://towhee.io/image-text-embedding/lightningdot/raw/branch/main/vec1.png" alt="result1" style="height:20px;"/>
-<img src="https://towhee.io/image-text-embedding/lightningdot/raw/branch/main/vec2.png" alt="result2" style="height:20px;"/>
+img_pipe = (
+    pipe.input('url')
+    .map('url', 'img', ops.image_decode.cv2_rgb())
+    .map('img', 'vec', ops.image_text_embedding.lightningdot(model_name='lightningdot_base', modality='image'))
+    .output('img', 'vec')
+)
 
-*Write a same pipeline with explicit inputs/outputs name specifications:*
+text_pipe = (
+    pipe.input('text')
+    .map('text', 'vec', ops.image_text_embedding.lightningdot(model_name='lightningdot_base', modality='text'))
+    .output('text', 'vec')
+)
 
-```python
-import towhee
-
-towhee.glob['path']('./teddy.jpg') \
-      .image_decode['path', 'img']() \
-      .image_text_embedding.lightningdot['img', 'vec'](model_name='lightningdot_base', modality='image') \
-      .select['img', 'vec']() \
-      .show()
-
-towhee.dc['text'](["A teddybear on a skateboard in Times Square."]) \
-      .image_text_embedding.lightningdot['text','vec'](model_name='lightningdot_base', modality='text') \
-      .select['text', 'vec']() \
-      .show()
+DataCollection(img_pipe('./teddy.jpg')).show()
+DataCollection(text_pipe('A teddybear on a skateboard in Times Square.')).show()
 ```
+
 <img src="https://towhee.io/image-text-embedding/lightningdot/raw/branch/main/tabular1.png" alt="result1" style="height:60px;"/>
 <img src="https://towhee.io/image-text-embedding/lightningdot/raw/branch/main/tabular2.png" alt="result2" style="height:60px;"/>