private void btnRefresh_Click(object sender, EventArgs e)
        {
            try
            {
                var scale = (float)numericUpDownHistogramScale.Value;

                switch (comboBoxHistogram.SelectedIndex)
                {
                case 0: Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(nlEngine.GetOriginalImageMatrix()), scale);  break;

                case 1: Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(nlEngine.GetErrorPredictedMatrix()), scale); break;

                case 2: Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(nlEngine.GetErrorPredictedQuantizedMatrix()), scale); break;

                case 3: Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(nlEngine.GetDecodedImageMatrix()), scale);   break;

                default:
                    if (bmpObject.GetBmpData() != null && bmpObject.GetBmpDataEncoded() == null)
                    {
                        Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(bmpObject.GetBmpData()), scale);
                    }
                    if (bmpObject.GetBmpDataEncoded() != null && bmpObject.GetBmpData() == null)
                    {
                        Helpers.DrawHistogram(pictureBoxHistogram, Helpers.CreateHistogram(bmpObject.GetBmpDataEncoded()), scale);
                    }
                    break;
                }
            }
            catch (NullReferenceException)
            {
                MessageBox.Show("Error, you forgot to load or to encode the image!");
            }
        }
        private void btnDecodeImage_Click(object sender, EventArgs e)
        {
            try
            {
                if (String.IsNullOrEmpty(inputFilePathDecoder))
                {
                    throw new NullReferenceException();
                }

                nlEngine = new NearLosslessEngine(bmpObject.GetBmpDataEncoded());

                nlEngine.DecompressImage(decodingP, decodingK, auxOriginalImage);

                pictureBoxDecodedImage.Image = Helpers.BuildBitmapFromMatrix(nlEngine.GetDecodedImageMatrix());

                MessageBox.Show("Image was decoded succesfully!");
                label15.Text  = "Decoded Image";
                isFileDecoded = true;
            }
            catch (NullReferenceException)
            {
                MessageBox.Show("Warning: You forgot to load Decoded Image!");
            }
        }