krita plugin

・server.py

import uvicorn
from fastapi import FastAPI
from pydantic import BaseModel
import cv2


app = FastAPI()


class Request(BaseModel):
    input_img_path: str
    output_img_path: str


@app.post("/blur")
async def f_blur(req: Request):
    input_img = cv2.imread(req.input_img_path)
    output_img = cv2.blur(input_img, (5, 5))
    cv2.imwrite(req.output_img_path, output_img)


def start():
    config = uvicorn.Config("server:app", host="127.0.0.1", port=8000, log_level="info")
    server = uvicorn.Server(config=config)
    server.run()


if __name__ == '__main__':
    start()

・blur_plugin.py

from krita import DockWidget
from PyQt5.QtWidgets import *
from .blur_action import BlurAction


DOCKER_TITLE = 'Blur Docker'


class BlurDock(DockWidget):

    def __init__(self):
        super().__init__()
        self.setWindowTitle(DOCKER_TITLE)

        self.action = BlurAction()

        self.button = QPushButton('Blur')
        self.button.clicked.connect(self.action.blur)

        self.layout = QVBoxLayout()
        self.layout.addWidget(self.button)
        widget = QWidget(self)
        widget.setLayout(self.layout)
        self.setWidget(widget)

    # notifies when views are added or removed
    # 'pass' means do not do anything
    def canvasChanged(self, canvas):
        pass

・blur_action.py

import os
import json
import urllib.request
import tempfile
from PyQt5.QtGui import *
from PyQt5.QtCore import *


class BlurAction:
    def __init__(self):
        self.url = 'http://127.0.0.1:8000/blur'
        self.input_img_name = 'input.png'
        self.output_img_name = 'output.png'

    def blur(self):
        with tempfile.TemporaryDirectory() as tempfolder:
            post_data = self.create_input_data(tempfolder)
            req = urllib.request.Request(
                self.url,
                headers={'Content-Type': 'application/json'},
                data=json.dumps(post_data).encode('utf-8')
            )
            with urllib.request.urlopen(req):
                self.apply_result(tempfolder)

    def create_input_data(self, tempfolder):

        doc = Krita.instance().activeDocument()
        pixel_bytes = doc.activeNode().pixelData(0, 0, doc.width(), doc.height())
        img = QImage(pixel_bytes, doc.width(), doc.height(), QImage.Format_RGBA8888).rgbSwapped()
        input_img_path = os.path.join(tempfolder, self.input_img_name)
        output_img_path = os.path.join(tempfolder, self.output_img_name)
        img.save(input_img_path, "PNG")

        post_data = {
            'input_img_path': input_img_path,
            'output_img_path': output_img_path
        }
        return post_data

    def apply_result(self, tempfolder):
        img = QImage()
        img.load(os.path.join(tempfolder, self.output_img_name))
        ptr = img.bits()
        ptr.setsize(img.byteCount())
        byte_array = QByteArray(ptr.asstring())
        doc = Krita.instance().activeDocument()
        doc.activeNode().setPixelData(byte_array, 0, 0, img.width(), img.height())
        doc.refreshProjection()