QuantizerMap.java

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 * PlantUML : a free UML diagram generator
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 * Original Author:  Arnaud Roques
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package net.sourceforge.plantuml.png.quantx;

import java.util.LinkedHashMap;
import java.util.Map;

/** Creates a dictionary with keys of colors, and values of count of the color */
public final class QuantizerMap  {
  Map<Integer, Integer> colorToCount;

  public Map<Integer, Integer> quantize(int[] pixels, int colorCount) {
    final Map<Integer, Integer> pixelByCount = new LinkedHashMap<>();
    for (int pixel : pixels) {
      final Integer currentPixelCount = pixelByCount.get(pixel);
      final int newPixelCount = currentPixelCount == null ? 1 : currentPixelCount + 1;
      pixelByCount.put(pixel, newPixelCount);
    }
    colorToCount = pixelByCount;
    return pixelByCount;
  }
}