private async void buttonSplit_Click(object sender, EventArgs e)
        {
            if (!this.buttonSplit.Enabled || this.textBoxFilename.Text == "" || this.textBoxSplits.Text == "")
            {
                return;
            }

            try {
                this.buttonSplit.Enabled = false;

                downloadForm.EnqueueJob(new FFMpegSplitJob(this.textBoxFilename.Text, this.textBoxSplits.Text));

                this.textBoxFilename.Text = "";
                this.textBoxSplits.Text   = "";
            } finally {
                this.buttonSplit.Enabled = true;
            }
        }