Question

I am trying to change image color dynamically in android .but it takes to much time .

Below function is used for changing color.

  public void greenColor(ImageView imageView,String fileName){
                System.out.println("in green color method");

             //initialize the Bitmap Object  

              Bitmap  bmp = BitmapFactory.decodeFile(fileName);
               //  Bitmap bmp = ((BitmapDrawable)imageView.getDrawable()).getBitmap();  
                //Guarantees that the image is decoded in the ARGB8888 format  
                bmp = bmp.copy(Bitmap.Config.ARGB_8888, true);  



                //Initialize the intArray with the same size as the number of pixels on the image  
                int[] intArray  = new int[bmp.getWidth()*bmp.getHeight()];  

                //copy pixel data from the Bitmap into the 'intArray' array  
                bmp.getPixels(intArray, 0, bmp.getWidth(), 0, 0, bmp.getWidth(), bmp.getHeight());  



                //replace the red pixels with yellow ones  
                try{
                    for (int i=0; i < intArray.length; i++)  
                    {  
                        //System.out.println("pixel value :"+intArray[i]);
                        //intArray[i] =  0xFFFF0000;  

                        if(intArray[i] == Color.WHITE)  
                        {  

                           System.out.println("color white ");
                        } else{
                            System.out.println(intArray[i]);
                            intArray[i]=Color.GREEN;
                        }
                    }  
                }catch(Exception e){
                    System.out.println("pixel error "+e);
                }


                //Initialize the bitmap, with the replaced color  
                bmp = Bitmap.createBitmap(intArray, bmp.getWidth(), bmp.getHeight(), Bitmap.Config.ARGB_8888);  

                //Draw the bitmap with the replaced color  
                imageView.setImageBitmap(bmp);  
               //----end color

        }

I’ve tried so much and did google search, but i am unable to solve my problem ,

Is there any technique to reduce image color change time in android?

Please help me …

Answer 1

in your case its taking time as you are converting the image into 2d array and checking at every index.

So if image if 2000*2000 size, just imagine how much you are processing.
If you want to change the alfa or tint then you should use the Bitmap APIs instead of doing it manually.