private void contrastToolStripMenuItem_Click(object sender, EventArgs e) { try { Parameter dlg = new Parameter(); dlg.nValue = 0; if (DialogResult.OK == dlg.ShowDialog()) { Bitmap m_Bitmap = (Bitmap)pic_box.Image; undo_picture = m_Bitmap; Bitmap mm_bit = (Bitmap)m_Bitmap.Clone(); if (BitmapFilter.Contrast(mm_bit, (sbyte)dlg.nValue)) this.Invalidate(); pic_box.Image = (Bitmap)mm_bit; pic_box.Invalidate(); } } catch { } }