imageをbyte配列に変換する
private byte[] ImageToBinary(Image targetImage) { using (var mem = new MemoryStream()) { mem.Position = 0; targetImage.Save(mem, ImageFormat.Bmp); byte[] buffer = new byte[mem.Length]; mem.Position = 0; mem.Read(buffer, 0, (int)mem.Length); mem.Close(); return buffer; } }