How to Change Pixel Color of an Image in C#.NET

Question

I am working with Images in Java, I have designed more over 100+ images(.png) format, They were all Trasparent and Black Color Drawing.

The problem is, Now I have been asked to change the color of the Drawing (Black -to ).

I have searched many code snipped at google,that changes the Bitmap (pixels) of the Image, but i am not guessing what i have to do to match the exact pixel and replace specially when the images if in Transparent mode. Below is the code in .Net (C#)

        Bitmap newBitmap = new Bitmap(scrBitmap.Width, scrBitmap.Height);         for (int i = 0; i < scrBitmap.Width; i++)         {             for (int j = 0; j < scrBitmap.Height; j++)             {                                     originalColor = scrBitmap.GetPixel(i, j);                 if(originalColor = Color.Black)                   newBitmap.SetPixel(i, j, Color.Red);             }         }                     return newBitmap; 

but it was not matching at all, I debugged it, throughout the file, there was no value of Red,Green,Blue parameters of Color (originalColor) variable.

Anybody can help?

Answer 1

Here is the Solution I have done with Pixels.

Attaching the source code so one can try the exact and get the result.

I have sample images of 128x128 (Width x Height).

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Drawing; using System.IO; //using System.Globalization;  namespace colorchange {    class Program    {       static void Main(string[] args)       {           try           {               Bitmap bmp = null;               //The Source Directory in debug\bin\Big\               string[] files = Directory.GetFiles("Big\\");               foreach (string filename in files)               {                  bmp = (Bitmap)Image.FromFile(filename);                                      bmp = ChangeColor(bmp);                  string[] spliter = filename.Split('\\');                  //Destination Directory debug\bin\BigGreen\                  bmp.Save("BigGreen\\" + spliter[1]);               }                                                             }            catch (System.Exception ex)            {               Console.WriteLine(ex.ToString());            }                    }                public static Bitmap ChangeColor(Bitmap scrBitmap)        {           //You can change your new color here. Red,Green,LawnGreen any..           Color newColor = Color.Red;           Color actualColor;                       //make an empty bitmap the same size as scrBitmap           Bitmap newBitmap = new Bitmap(scrBitmap.Width, scrBitmap.Height);           for (int i = 0; i < scrBitmap.Width; i++)           {              for (int j = 0; j < scrBitmap.Height; j++)              {                 //get the pixel from the scrBitmap image                 actualColor = scrBitmap.GetPixel(i, j);                 // > 150 because.. Images edges can be of low pixel colr. if we set all pixel color to new then there will be no smoothness left.                 if (actualColor.A > 150)                     newBitmap.SetPixel(i, j, newColor);                 else                     newBitmap.SetPixel(i, j, actualColor);              }           }                       return newBitmap;        }    } } 

//Below is the sample image and different results by applying different color

Code modifications will be highly appreciated.