private void especificaciónHistogramaToolStripMenuItem_Click(object sender, EventArgs e) { try { ImageForm Image1 = (ImageForm)ActiveMdiChild; OpenFileDialog OpenFile = new OpenFileDialog(); OpenFile.Filter = " Archivos JPEG(*.jpg)|*.jpg| Archivos TIFF(*.tif, *.tiff)|*.tif; *.tiff"; OpenFile.InitialDirectory = "C:\\Users\\Jose\\Desktop\\Imagenes"; if (OpenFile.ShowDialog() == DialogResult.OK) { ImageForm ImageForm = new ImageForm(); ImageForm.MdiParent = this; ImageForm.Show(); String Dir = OpenFile.FileName; ImageForm.Text = Dir; ImageForm.HistogramSpecification(Dir, Image1.getR(), Image1.getPicture()); writePanel(); } } catch (NullReferenceException) { MessageBox.Show("No hay ninguna foto seleccionada"); } }