app.py

import os
from flask import Flask, render_template, request, jsonify
import cv2
import numpy as np
from werkzeug.utils import secure_filename
import base64

app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = 'static/uploaded'
app.config['ALLOWED_EXTENSIONS'] = {'png', 'jpg', 'jpeg'}

def allowed_file(filename):
    return '.' in filename and \
           filename.rsplit('.', 1)[1].lower() in app.config['ALLOWED_EXTENSIONS']

def adjust_curves(image, r_curve, g_curve, b_curve, y_curve):
    # 各チャンネルを分離
    b, g, r = cv2.split(image)
    
    # 明るさチャンネルを計算
    y = (0.299 * r + 0.587 * g + 0.114 * b).astype(np.uint8)
    
    # 各チャンネルにカーブを適用
    b = apply_lut(b, b_curve)
    g = apply_lut(g, g_curve)
    r = apply_lut(r, r_curve)
    y_adjusted = apply_lut(y, y_curve)
    
    # 明るさ調整をRGBに反映
    ratio = np.where(y == 0, 0, y_adjusted / y).clip(0, 3)
    r = (r * ratio).clip(0, 255).astype(np.uint8)
    g = (g * ratio).clip(0, 255).astype(np.uint8)
    b = (b * ratio).clip(0, 255).astype(np.uint8)
    
    return cv2.merge((b, g, r))

def apply_lut(channel, curve_points):
    x = np.array([0, 64, 128, 192, 255])
    y = np.array(curve_points)
    lut = np.interp(np.arange(256), x, y).astype(np.uint8)
    return cv2.LUT(channel, lut)

@app.route('/')
def index():
    default_curve = [0, 64, 128, 192, 255]
    return render_template('index.html',
                         r_curve=default_curve,
                         g_curve=default_curve,
                         b_curve=default_curve,
                         y_curve=default_curve)

@app.route('/api/process_image', methods=['POST'])
def process_image():
    if request.method == 'OPTIONS':
        return _build_cors_preflight_response()
    elif request.method == 'POST':
        # リクエストデータを取得
        data = request.json
        file_data = data['image'].split(',')[1]
        img_bytes = base64.b64decode(file_data)
        
        # バイトデータから画像を読み込み
        nparr = np.frombuffer(img_bytes, np.uint8)
        img = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
        img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
        
        # カーブパラメータを取得
        r_curve = [int(x) for x in data['r_curve']]
        g_curve = [int(x) for x in data['g_curve']]
        b_curve = [int(x) for x in data['b_curve']]
        y_curve = [int(x) for x in data['y_curve']]
        
        # 画像処理
        adjusted_img = adjust_curves(img, r_curve, g_curve, b_curve, y_curve)
        
        # 画像をJPEGにエンコード
        _, buffer = cv2.imencode('.jpg', cv2.cvtColor(adjusted_img, cv2.COLOR_RGB2BGR))
        img_base64 = base64.b64encode(buffer).decode('utf-8')
        
        return _corsify_response(jsonify({
            'status': 'success',
            'image': 'data:image/jpeg;base64,' + img_base64
        }))
    except Exception as e:
        return jsonify({
            'status': 'error',
            'message': str(e)
        }), 500
def _build_cors_preflight_response():
    response = jsonify({'message': 'Preflight Request'})
    response.headers.add("Access-Control-Allow-Origin", "*")
    response.headers.add("Access-Control-Allow-Headers", "*")
    response.headers.add("Access-Control-Allow-Methods", "*")
    return response

def _corsify_response(response):
    response.headers.add("Access-Control-Allow-Origin", "*")
    return response
if __name__ == '__main__':
    os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
    app.run(debug=True, port=7860, host="0.0.0.0")