Image To Grayscale Script

An article by mgear    No Comments

Quick test trying to convert this Basic256 script into Unity c# (trying to keep it close to original code..)
maybe still some problems as the output seems darker than the example..

http://rosettacode.org/wiki/Grayscale_image#BASIC256

Source C# (Image2Grayscale.cs)

// Original source: http://rosettacode.org/wiki/Grayscale_image#BASIC256

using UnityEngine;
using System.Collections;

public class Image2Grayscale : MonoBehaviour
{
string fileName = "BASIC256_greyscale_Mona_Lisa";
Texture2D graph;

void Start ()
{
LoadImage();
ConvertToGrayscale();
}

void LoadImage()
{
graph = Resources.Load(fileName, typeof(Texture2D)) as Texture2D;
}

void ConvertToGrayscale()
{
Color32[] pixels = graph.GetPixels32();
for (int x=0;x<graph.width;x++)
{
for (int y=0;y<graph.height;y++)
{
Color32 pixel = pixels[x+y*graph.width];
int p =  ( (256 * 256 + pixel.r) * 256 + pixel.b) * 256 + pixel.g;
int b = p % 256;
p = Mathf.FloorToInt(p / 256);
int g = p % 256;
p = Mathf.FloorToInt (p / 256);
int r = p % 256;
float l = (0.2126f*r/255f) + 0.7152f*(g/255f) + 0.0722f*(b/255f);
Color c = new Color(l,l,l,1);
graph.SetPixel(x,y,c);
}
}
graph.Apply(false);
var bytes = graph.EncodeToPNG();
System.IO.File.WriteAllBytes(Application.dataPath + "ImageSaveTest.png", bytes);
}
}