Processing image files uploaded by streamlit Library

  steamlit It is an interface that can quickly build a website . In the training program arranged by the school , We want to realize the design and implementation of content-based image retrieval system . The branch task is to retrieve the uploaded image .
   We used steamlit Of uploadfile Components , This component can upload the pictures we need to the back-end program in bytes . Now the problem is how to analyze this 16 Base file .
The solution is PIL Library Image.open(); He can not only directly read the files under the file path , You can also read files through byte streams .

from io import BytesIO
import numpy as np
from PIL import Image
import streamlit as st
import  cv2

# establish file_uploader Components 
uploaded_file = st.file_uploader("Choose a file")
if uploaded_file is not None:
     # To read file as bytes:
     bytes_data = uploaded_file.getvalue()
     # Convert byte data into byte stream 
     bytes_data = BytesIO(bytes_data)
     #Image.open() Byte stream can be read 
     capture_img = Image.open(bytes_data)
     capture_img = cv2.cvtColor(np.asarray(capture_img), cv2.COLOR_RGB2BGR)