在GBASE8a数据库中，使用图片进行信息检索

1   主要解决问题

（1） 随着ai技术的日新月异，传统数据库检索技术已经由单纯依赖文本到依赖声音、图像、视频等多模态技术方向发展。本demo旨在探索通过图像在8a数据库内检索图像信息。

2   部署方式

（1） 在Gbase8a数据库中新建表，并导入数据（包含图片信息），如下例

datafile文件（图片文件按指定目录存放）：

1,gou1,./gou1.jpg,小强
2,gou2,./gou2.jpg,旺财
3,mao1,./mao1.jpg,花花
4,mao2,./mao2.jpg,球球
 

CREATE TABLE "zhao" (
 "id" int(11) DEFAULT NULL,
 "ename" varchar(50) DEFAULT NULL,
 "image_data" longblob,        --最大可存储64MB信息
 "cname" varchar(50) DEFAULT NULL
) 

Load data infile 'file://192.168.1.5//home/gbase/comparepic/datafile.txt' into table test.zhao fields terminated by ','  table_fields 'id,ename,image_data type_url,cname'       

--图片在库内以二进制形式存储

（2）新建目录edp，将app.py放入，其内新建templates 和uploads 目录，将index.html文件放入templates 内

（3）执行python.py app

（4）弹出server运行窗口后最小化

3    使用方式

（1）在浏览器内输入：127.0.0.1:5050

（2）在页面内选择库名，表名，以及包含图像字段的字段名

（3）选择要用来进行检索的图片

（4）选择与该图片匹配程度的值。该值越接近0，匹配程度越低， 越接近1，匹配程度越高

（5）点击“使用图片检索”按钮

4   演示样例

启动server窗口

 库名、 表名、字段名（含图片的）， 用来检索的图片文件，都选择好。点击使用图片检索，下方会显示出查询出的记录信息。

5   参考文件

（1）app.py文件

import os
from flask import Flask, render_template, request, send_from_directory, jsonify
import pymysql
from io import BytesIO
from PIL import Image
import torch
import torchvision.models as models
import torchvision.transforms as transforms
import numpy as np
from werkzeug.utils import secure_filename
import base64

app = Flask(__name__)

 
DB_CONFIG = {
    'host': '192.168.1.5',
    'user': 'gbase',
    'password': 'gbase20110531',
    'charset': 'utf8mb4',
    'port': 5258
}

 
UPLOAD_FOLDER = 'uploads'
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER

 
if not os.path.exists(UPLOAD_FOLDER):
    os.makedirs(UPLOAD_FOLDER)

 
model = models.resnet50(pretrained=True)
model.eval()

 
transform = transforms.Compose([
    transforms.Resize((224, 224)),
    transforms.ToTensor(),
    transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
])


@app.route('/', methods=['GET', 'POST'])
def index():
    if request.method == 'POST':
 
        dbname = request.form.get('dbname')
        tbname = request.form.get('tbname')
        column_name = request.form.get('column_name')
        sample_file = request.files['sample']
        similarity_threshold = float(request.form.get('similarity_threshold'))

 
        if sample_file:
            filename = secure_filename(sample_file.filename)
            sample_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
            sample_file.save(sample_path)

 
            sample_image = Image.open(sample_path)
            sample_image = transform(sample_image).unsqueeze(0)
            with torch.no_grad():
                sample_features = model(sample_image).squeeze().numpy()

 
            conn = pymysql.connect(**DB_CONFIG)
            cursor = conn.cursor()

 
            query = f"SELECT * FROM {dbname}.{tbname}"
            cursor.execute(query)
            results = cursor.fetchall()

 
            matching_records = []
            for row in results:
 
                image_index = [col[0] for col in cursor.description].index(column_name)
                image_data = row[image_index]
                if image_data:
                    candidate_image = Image.open(BytesIO(image_data))
                    candidate_image = transform(candidate_image).unsqueeze(0)
                    with torch.no_grad():
                        candidate_features = model(candidate_image).squeeze().numpy()

 
                    similarity = np.dot(sample_features, candidate_features) / (
                            np.linalg.norm(sample_features) * np.linalg.norm(candidate_features))

                    if similarity >= similarity_threshold:
 
                        encoded_image = base64.b64encode(image_data).decode('utf-8')
                        new_row = list(row)
                        new_row[image_index] = encoded_image
                        matching_records.append(new_row)

            cursor.close()
            conn.close()

            return render_template('index.html', dbnames=get_dbnames(),
                                   tbnames=get_tbnames(dbname),
                                   column_names=get_column_names(dbname, tbname),
                                   sample_image=filename,
                                   matching_records=matching_records,
                                   columns=[col[0] for col in cursor.description],
                                   column_name=column_name)

    dbnames = get_dbnames()
    return render_template('index.html', dbnames=dbnames, tbnames=[], column_names=[])


def get_dbnames():
    conn = pymysql.connect(**DB_CONFIG)
    cursor = conn.cursor()
    query = "SELECT distinct dbname FROM gbase.table_distribution"
    cursor.execute(query)
    dbnames = [row[0] for row in cursor.fetchall()]
    cursor.close()
    conn.close()
    return dbnames


def get_tbnames(dbname):
    conn = pymysql.connect(**DB_CONFIG)
    cursor = conn.cursor()
    query = f"SELECT tbname FROM gbase.table_distribution WHERE dbname = '{dbname}'"
    cursor.execute(query)
    tbnames = [row[0] for row in cursor.fetchall()]
    cursor.close()
    conn.close()
    return tbnames


def get_column_names(dbname, tbname):
    conn = pymysql.connect(**DB_CONFIG)
    cursor = conn.cursor()
    query = "SELECT COLUMN_NAME FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = %s AND TABLE_NAME = %s"
    cursor.execute(query, (dbname, tbname))
    column_names = [row[0] for row in cursor.fetchall()]
    cursor.close()
    conn.close()
    return column_names


@app.route('/uploads/<filename>')
def uploaded_file(filename):
    return send_from_directory(app.config['UPLOAD_FOLDER'], filename)


@app.route('/get_tables')
def get_tables():
    dbname = request.args.get('dbname')
    tbnames = get_tbnames(dbname)
    return jsonify({'tbnames': tbnames})


@app.route('/get_columns')
def get_columns():
    dbname = request.args.get('dbname')
    tbname = request.args.get('tbname')
    column_names = get_column_names(dbname, tbname)
    return jsonify({'column_names': column_names})


if __name__ == '__main__':
    app.run(debug=True)
    

（2）index.html文件

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>图像检索DEMO</title>
    <script src="https://unpkg.com/@tailwindcss/browser@4"></script>
    <link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.7.2/css/all.min.css" rel="stylesheet">
</head>

<body class="bg-gray-100 font-sans">
    <div class="container mx-auto p-8">
        <h1 class="text-3xl font-bold text-center mb-8">图像检索应用</h1>
        <form method="post" enctype="multipart/form-data" class="bg-white p-6 rounded shadow-md">
            <table class="w-full">
                <tbody>
                    <tr>
                        <td class="py-2 pr-4">
                            <label for="dbname" class="block text-sm font-medium text-gray-700">选择库名:</label>
                        </td>
                        <td class="py-2">
                            <select name="dbname" id="dbname" onchange="updateTables()"
                                class="mt-1 block w-full py-2 px-3 border border-gray-300 bg-white rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm">
                                {% for dbname in dbnames %}
                                <option value="{{ dbname }}">{{ dbname }}</option>
                                {% endfor %}
                            </select>
                        </td>
                    </tr>
                    <tr>
                        <td class="py-2 pr-4">
                            <label for="tbname" class="block text-sm font-medium text-gray-700">选择表名:</label>
                        </td>
                        <td class="py-2">
                            <select name="tbname" id="tbname" onchange="updateColumns()"
                                class="mt-1 block w-full py-2 px-3 border border-gray-300 bg-white rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm">
                                <!-- 初始为空，后续动态填充 -->
                            </select>
                        </td>
                    </tr>
                    <tr>
                        <td class="py-2 pr-4">
                            <label for="column_name" class="block text-sm font-medium text-gray-700">选择字段名:</label>
                        </td>
                        <td class="py-2">
                            <select name="column_name" id="column_name"
                                class="mt-1 block w-full py-2 px-3 border border-gray-300 bg-white rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm">
                                <!-- 初始为空，后续动态填充 -->
                            </select>
                        </td>
                    </tr>
                    <tr>
                        <td class="py-2 pr-4">
                            <label for="sample" class="block text-sm font-medium text-gray-700">选择样本图片:</label>
                        </td>
                        <td class="py-2">
                            <input type="file" name="sample" id="sample"
                                class="mt-1 block w-full py-2 px-3 border border-gray-300 bg-white rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm">
                            {% if sample_image %}
                            <img src="{{ url_for('uploaded_file', filename=sample_image) }}" alt="样本图片" width="200"
                                class="mt-2">
                            {% endif %}
                        </td>
                    </tr>
                    <tr>
                        <td class="py-2 pr-4">
                            <label for="similarity_threshold"
                                class="block text-sm font-medium text-gray-700">输入匹配度:</label>
                        </td>
                        <td class="py-2">
                            <input type="number" name="similarity_threshold" id="similarity_threshold" step="0.01"
                                value="0.8"
                                class="mt-1 block w-full py-2 px-3 border border-gray-300 bg-white rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm">
                        </td>
                    </tr>
                    <tr>
                        <td colspan="2" class="py-4">
                            <input type="submit" value="使用图片检索"
                                class="bg-blue-500 hover:bg-blue-600 text-white py-2 px-4 rounded-md shadow-md focus:outline-none focus:ring-2 focus:ring-blue-500 focus:ring-opacity-50">
                        </td>
                    </tr>
                </tbody>
            </table>
        </form>

        {% if matching_records %}
        <h2 class="text-2xl font-bold mt-8 mb-4">匹配结果:</h2>
        <table class="w-full bg-white rounded shadow-md">
            <thead>
                <tr>
                    {% for column in columns %}
                    <th class="py-3 px-6 text-left text-sm font-medium text-gray-700 border-b border-gray-200">
                        {{ column }}</th>
                    {% endfor %}
                </tr>
            </thead>
            <tbody>
                {% for record in matching_records %}
                <tr>
                    {% for value in record %}
                    {% set i = loop.index0 %} {# 获取当前循环的索引，从0开始 #}
                    {% if columns[i] == column_name %}
                    <td class="py-4 px-6 border-b border-gray-200"><img
                            src="data:image/jpeg;base64,{{ value }}" alt="图片" width="100"></td>
                    {% else %}
                    <td class="py-4 px-6 border-b border-gray-200">{{ value }}</td>
                    {% endif %}
                    {% endfor %}
                </tr>
                {% endfor %}
            </tbody>
        </table>
        {% endif %}
    </div>

    <script>
        function updateTables() {
            var dbname = document.getElementById('dbname').value;
            var xhr = new XMLHttpRequest();
            xhr.open('GET', `/get_tables?dbname=${dbname}`, true);
            xhr.onreadystatechange = function () {
                if (xhr.readyState === 4 && xhr.status === 200) {
                    var response = JSON.parse(xhr.responseText);
                    var tbnames = response.tbnames;
                    var tbnameSelect = document.getElementById('tbname');
                    tbnameSelect.innerHTML = '';
                    tbnames.forEach(function (tbname) {
                        var option = document.createElement('option');
                        option.value = tbname;
                        option.textContent = tbname;
                        tbnameSelect.appendChild(option);
                    });
                    // 初始化列名选择框
                    var columnSelect = document.getElementById('column_name');
                    columnSelect.innerHTML = '';
                }
            };
            xhr.send();
        }

        function updateColumns() {
            var dbname = document.getElementById('dbname').value;
            var tbname = document.getElementById('tbname').value;
            var xhr = new XMLHttpRequest();
            xhr.open('GET', `/get_columns?dbname=${dbname}&tbname=${tbname}`, true);
            xhr.onreadystatechange = function () {
                if (xhr.readyState === 4) {
                    if (xhr.status === 200) {
                        try {
                            var response = JSON.parse(xhr.responseText);
                            var column_names = response.column_names;
                            var columnSelect = document.getElementById('column_name');
                            columnSelect.innerHTML = '';
                            column_names.forEach(function (column_name) {
                                var option = document.createElement('option');
                                option.value = column_name;
                                option.textContent = column_name;
                                columnSelect.appendChild(option);
                            });
                        } catch (error) {
                            console.error('解析 JSON 失败:', error);
                        }
                    } else {
                        console.error('请求失败，状态码:', xhr.status);
                    }
                }
            };
            xhr.send();
        }
    </script>
</body>

</html>