Histogram is used to calculate a histogram for a surface (in a selection, if desired). This can then be used to retrieve percentile, average, peak, and distribution information.
Inheritance: Histogram
		public void SetFromLeveledHistogram (HistogramRgb inputHistogram, LevelOp upo)
		{
			if (inputHistogram == null || upo == null) {
				return;
			}

			Clear ();

			float[] before = new float[3];
			float[] slopes = new float[3];

			for (int c = 0; c < 3; c++) {
				long[] channelHistogramOutput = histogram[c];
				long[] channelHistogramInput = inputHistogram.histogram[c];

				for (int v = 0; v <= 255; v++) {
					ColorBgra after = ColorBgra.FromBgr ((byte)v, (byte)v, (byte)v);

					upo.UnApply (after, before, slopes);

					if (after[c] > upo.ColorOutHigh[c]
					    || after[c] < upo.ColorOutLow[c]
					    || (int)Math.Floor (before[c]) < 0
					    || (int)Math.Ceiling (before[c]) > 255
					    || float.IsNaN (before[c])) {
						channelHistogramOutput[v] = 0;
					} else if (before[c] <= upo.ColorInLow[c]) {
						channelHistogramOutput[v] = 0;

						for (int i = 0; i <= upo.ColorInLow[c]; i++) {
							channelHistogramOutput[v] += channelHistogramInput[i];
						}
					} else if (before[c] >= upo.ColorInHigh[c]) {
						channelHistogramOutput[v] = 0;

						for (int i = upo.ColorInHigh[c]; i < 256; i++) {
							channelHistogramOutput[v] += channelHistogramInput[i];
						}
					} else {
						channelHistogramOutput[v] = (int)(slopes[c] * Utility.Lerp (
						    channelHistogramInput[(int)Math.Floor (before[c])],
						    channelHistogramInput[(int)Math.Ceiling (before[c])],
						    before[c] - Math.Floor (before[c])));
					}
				}
			}

			OnHistogramUpdated ();
		}
        public void SetFromLeveledHistogram(HistogramRgb inputHistogram, LevelOp upo)
        {
            if (inputHistogram == null || upo == null)
            {
                return;
            }

            Clear();

            float[] before = new float[3];
            float[] slopes = new float[3];

            for (int c = 0; c < 3; c++)
            {
                long[] channelHistogramOutput = histogram[c];
                long[] channelHistogramInput  = inputHistogram.histogram[c];

                for (int v = 0; v <= 255; v++)
                {
                    ColorBgra after = ColorBgra.FromBgr((byte)v, (byte)v, (byte)v);

                    upo.UnApply(after, before, slopes);

                    if (after[c] > upo.ColorOutHigh[c] ||
                        after[c] < upo.ColorOutLow[c] ||
                        (int)Math.Floor(before[c]) < 0 ||
                        (int)Math.Ceiling(before[c]) > 255 ||
                        float.IsNaN(before[c]))
                    {
                        channelHistogramOutput[v] = 0;
                    }
                    else if (before[c] <= upo.ColorInLow[c])
                    {
                        channelHistogramOutput[v] = 0;

                        for (int i = 0; i <= upo.ColorInLow[c]; i++)
                        {
                            channelHistogramOutput[v] += channelHistogramInput[i];
                        }
                    }
                    else if (before[c] >= upo.ColorInHigh[c])
                    {
                        channelHistogramOutput[v] = 0;

                        for (int i = upo.ColorInHigh[c]; i < 256; i++)
                        {
                            channelHistogramOutput[v] += channelHistogramInput[i];
                        }
                    }
                    else
                    {
                        channelHistogramOutput[v] = (int)(slopes[c] * Utility.Lerp(
                                                              channelHistogramInput[(int)Math.Floor(before[c])],
                                                              channelHistogramInput[(int)Math.Ceiling(before[c])],
                                                              before[c] - Math.Floor(before[c])));
                    }
                }
            }

            OnHistogramUpdated();
        }