Remove empty histograms

6 years ago · f5d7d2c71a
1 changed files with 2 additions and 0 deletions
--- a/src/ImageSharp/Formats/WebP/Lossless/HistogramEncoder.cs
+++ b/src/ImageSharp/Formats/WebP/Lossless/HistogramEncoder.cs
@ -68,9 +68,11 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossless

            // Cubic ramp between 1 and MaxHistoGreedy:
            int thresholdSize = (int)(1 + (x * x * x * (MaxHistoGreedy - 1)));
+            RemoveEmptyHistograms(imageHisto);
            bool doGreedy = HistogramCombineStochastic(imageHisto, thresholdSize);
            if (doGreedy)
            {
+                RemoveEmptyHistograms(imageHisto);
                HistogramCombineGreedy(imageHisto);
            }