C#

using (FileStream Ciphertext = new FileStream(_InputPath, FileMode.Open, FileAccess.Read, FileShare.None)) //For Plaintext Stream
{
    using (FileStream PlainText = new FileStream(_OutputPath, FileMode.Create, FileAccess.Write, FileShare.None)) //For Ciphertext Stream
    {
        using (CryptoStream CStreamWriter = new CryptoStream(PlainText, Decryptor, CryptoStreamMode.Write)) //For CryptoStream Writer
        {
            byte[] CTextData = new byte[Ciphertext.Length]; //EXCEPTION THROWN HERE

private void OnBrowse(object sender, EventArgs e)
{
    var fd = new OpenFileDialog
        {
            Filter = "Image Files(*.BMP;*.JPG;*.GIF)|*.BMP;*.JPG;*.GIF|All files (*.*)|*.*",
            Multiselect = false
        };

        if (fd.ShowDialog() == DialogResult.OK)
            pictureBox1.Load(fd.FileName);
}

private void OnSave(object sender, EventArgs e)
{
    try
    {
        pictureBox1.Image.Save(@"c:\src\test\image.bmp", ImageFormat.Bmp);
    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
}