Hjg.Pngcs.PngWriter.FilterRow C# (CSharp) Method

        private void FilterRow(int rown)
        {
            // warning: filters operation rely on: "previos row" (rowbprev) is
            // initialized to 0 the first time
            if (filterStrat.shouldTestAll(rown)) {
                FilterRowNone();
                reportResultsForFilter(rown, FilterType.FILTER_NONE, true);
                FilterRowSub();
                reportResultsForFilter(rown, FilterType.FILTER_SUB, true);
                FilterRowUp();
                reportResultsForFilter(rown, FilterType.FILTER_UP, true);
                FilterRowAverage();
                reportResultsForFilter(rown, FilterType.FILTER_AVERAGE, true);
                FilterRowPaeth();
                reportResultsForFilter(rown, FilterType.FILTER_PAETH, true);
            }
            FilterType filterType = filterStrat.gimmeFilterType(rown, true);
            rowbfilter[0] = (byte)(int)filterType;
            switch (filterType) {
                case Hjg.Pngcs.FilterType.FILTER_NONE:
                    FilterRowNone();
                    break;
                case Hjg.Pngcs.FilterType.FILTER_SUB:
                    FilterRowSub();
                    break;
                case Hjg.Pngcs.FilterType.FILTER_UP:
                    FilterRowUp();
                    break;
                case Hjg.Pngcs.FilterType.FILTER_AVERAGE:
                    FilterRowAverage();
                    break;
                case Hjg.Pngcs.FilterType.FILTER_PAETH:
                    FilterRowPaeth();
                    break;
                default:
                    throw new PngjOutputException("Filter type " + filterType + " not implemented");
            }
            reportResultsForFilter(rown, filterType, false);
        }