I have used the databae table used in my article.

Upload and save (insert) multiple files to database in ASP.Net using C# and VB.Net

And then I made the following changes to the sample code of the following article Capture Image (Photo) from Web Camera (webcam) in ASP.Net using C# and VB.Net

Namespaces

using System.IO;
using System.Web.Services;
using System.Configuration;
using System.Data.SqlClient;

Code

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        if (Request.InputStream.Length > 0)
        {
            using (StreamReader reader = new StreamReader(Request.InputStream))
            {
                string hexString = Server.UrlEncode(reader.ReadToEnd());
                string imageName = DateTime.Now.ToString("dd-MM-yy hh-mm-ss");
                string imagePath = string.Format("~/Captures/{0}.png", imageName);
                byte[] bytes = ConvertHexToBytes(hexString);
                File.WriteAllBytes(Server.MapPath(imagePath), bytes);
                string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
                using (SqlConnection con = new SqlConnection(constr))
                {
                    string query = "INSERT INTO tblFiles VALUES(@Name, @ContentType, @Data);SELECT SCOPE_IDENTITY()";
                    using (SqlCommand cmd = new SqlCommand(query))
                    {
                        cmd.Connection = con;
                        cmd.Parameters.AddWithValue("@Name", imageName);
                        cmd.Parameters.AddWithValue("@ContentType", "image/png");
                        cmd.Parameters.AddWithValue("@Data", bytes);
                        con.Open();
                        Session["CapturedImageId"] = cmd.ExecuteScalar();
                        con.Close();
                    }
                }
            }
        }
    }
}

private static byte[] ConvertHexToBytes(string hex)
{
    byte[] bytes = new byte[hex.Length / 2];
    for (int i = 0; i < hex.Length; i += 2)
    {
        bytes[i / 2] = Convert.ToByte(hex.Substring(i, 2), 16);
    }
    return bytes;
}

[WebMethod(EnableSession = true)]
public static string GetCapturedImage()
{
    string url = string.Empty;
    int imageId = Convert.ToInt32(HttpContext.Current.Session["CapturedImageId"]);
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = "SELECT Data FROM tblFiles WHERE Id = @Id";
            cmd.Parameters.AddWithValue("@Id", imageId);
            cmd.Connection = con;
            con.Open();
            byte[] bytes = (byte[])cmd.ExecuteScalar();
            url = "data:image/png;base64," + Convert.ToBase64String(bytes, 0, bytes.Length);
            con.Close();
        }
    }
    HttpContext.Current.Session["CapturedImageId"] = null;
    return url;
}