未显示PHP中的Oracle Blob as img src

<?php
// 数据库连接信息
$host = 'your_host';
$user = 'your_user';
$password = 'your_password';
$dbname = 'your_dbname';

// 连接数据库
$conn = oci_connect($user, $password, $host . '/' . $dbname);

if (!$conn) {
    die('Connection failed: ' . oci_error());
}

// 查询BLOB数据
$sql = "SELECT blob_column FROM your_table WHERE id = :id";
$stmt = oci_parse($conn, $sql);
$id = 1; // 假设我们要查询的ID是1
oci_bind_by_name($stmt, ':id', $id);
oci_execute($stmt);

if ($row = oci_fetch_assoc($stmt)) {
    $blob_data = $row['BLOB_COLUMN'];

    // 设置正确的MIME类型
    header('Content-Type: image/jpeg'); // 根据实际情况修改MIME类型

    // 输出BLOB数据
    echo $blob_data;
} else {
    echo "No data found";
}

// 关闭连接
oci_free_statement($stmt);
oci_close($conn);
?>