#概要
canvasのデータをflask_socketioで、送り
サーバー側でbase64デコード、numpyにして
opencvで合成し、再度base64にエンコードして送り返す
いろいろ試しましたが、この方法じゃないと、ノイズが出たりとうまくいきませんでした。
#環境
mac10.15
python3.9.2
#template
top.html
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<script src="https://cdn.socket.io/3.1.3/socket.io.min.js" integrity="sha384-cPwlPLvBTa3sKAgddT6krw0cJat7egBga3DJepJyrLl4Q9/5WLra3rrnMcyTyOnh" crossorigin="anonymous"></script>
</head>
<body>
<br>
<button id="scan">scan</button>
<br>
<img id="img1" src="{{ url_for('static', filename = 'bg.jpg') }}" width=300 height=200>
<img id="img2" src="{{ url_for('static', filename = '02.jpg') }}" width=300 height=200>
<canvas id="compimg" width=300 height=200></canvas>
</body>
<script>
const imgw = 300;
const imgh = 200;
var scanButton = document.getElementById('scan');
scanButton.addEventListener('click', function() {
const canvas1 = document.createElement("canvas");
canvas1.width = imgw;
canvas1.height = imgh;
const img1 = document.getElementById("img1");
const ctx1 = canvas1.getContext("2d");
ctx1.drawImage(img1, 0, 0);
const canvas1data = canvas1.toDataURL("image/jpeg");
const canvas2 = document.createElement("canvas");
canvas2.width = imgw;
canvas2.height = imgh;
const img2 = document.getElementById("img2");
const ctx2 = canvas2.getContext("2d");
ctx2.drawImage(img2, 0, 0);
const canvas2data = canvas2.toDataURL("image/jpeg");
socket.emit( 'image', canvas1data, canvas2data);
});
const socket = io.connect();
socket.on('connect', () => {
console.log('connect');
});
socket.on('response', function(msg) {
console.log('response');
const compimg = document.getElementById('compimg');
const compimgCtx = compimg.getContext('2d')
var itemimage = new Image();
itemimage.src= "data:image/jpeg;base64,"+msg.image;
itemimage.onload = function () {
compimgCtx.drawImage(itemimage, 0, 0, imgw, imgh)
}
});
</script>
</html>
#flask
app.py
from flask import Flask, render_template, request
from flask_socketio import SocketIO, emit, disconnect
import cv2
import numpy as np
import base64
from PIL import Image
import io
app = Flask(__name__)
async_mode = None
socketio = SocketIO(app, async_mode=async_mode,async_handlers=True)
@socketio.event
def connect():
print("connect")
@app.route('/')
def top():
return render_template('top.html')
@socketio.event
def image(img_base64,imgbg_base64):#base64
print("recieve")
im = Image.open(io.BytesIO(base64.b64decode(img_base64.split(',')[1])))
imbg = Image.open(io.BytesIO(base64.b64decode(imgbg_base64.split(',')[1])))
img1 = np.array(im)
h,w = img1.shape[:2]
imbgresize = imbg.resize((w, h))
img2 = np.array(imbgresize)
dst = img1 * 0.5 + img2 * 0.5
if dst is None:
print("Image is empty!!")
else:
print("Image")
buffer = io.BytesIO()
Image.fromarray(dst.astype(np.uint8)).save(buffer, format="JPEG")
new_image = base64.b64encode(buffer.getvalue()).decode("ascii")
emit('response',{'image': new_image})
if __name__ == "__main__":
app.run( port=8000, debug=True)
#使用した素材
https://www.pakutaso.com/
#完成
