public static Texture2D GetEntropyImage(Texture2D texture, int sampleArea, out float[,] returnEntropyTable)
{
Texture2D entropyTexture = new Texture2D(texture.width, texture.height);
Color[] oldColors = texture.GetPixels();
Color[] newColors = new Color[oldColors.Length];
float[,] entropyTable = new float[texture.width, texture.height];
LookupTable <float, float> lookupTable = new LookupTable <float, float>();
Histogram histogram = new Histogram();
for (int i = 0; i < oldColors.Length; i++)
{
int thisY = Mathf.FloorToInt(i / texture.width);
int thisX = i - thisY * texture.width;
//For each pixel check sample area around it to set this pixel entropy
for (int x = Mathf.Max(thisX - sampleArea, 0); x <= thisX + sampleArea && x < texture.width; x++)
{
for (int y = Mathf.Max(thisY - sampleArea, 0); y <= thisY + sampleArea && y < texture.height; y++)
{
histogram.AddPixel(oldColors[x + y * texture.width]);
}
}
float entropy = histogram.EntropyOfHistogram(lookupTable);
histogram.Clear();
newColors[i] = new Color(entropy / 5f, entropy / 5f, entropy / 5f);
entropyTable[thisX, thisY] = entropy;
}
entropyTexture.filterMode = FilterMode.Point;
entropyTexture.SetPixels(newColors);
entropyTexture.Apply();
returnEntropyTable = entropyTable;
return(entropyTexture);
}
