Image from gallery convert to grayscale by click on button (Android)

Question

I want to know how to change the colour of image from the gallery by clicking on button. i have multiple activities that need to be done. I already pass the image from the gallery to the other activity by using intent. what i need to do now is to convert that image from gallery to grayscale by click on button.. could you give some idea?

and another one, what the image processing library that can used in android? thanks.

possible duplicate of [Convert a Bitmap to GrayScale in Android](http://stackoverflow.com/questions/3373860/convert-a-bitmap-to-grayscale-in-android) — kiranpradeep, Mar 25 '15 at 15:58

score 1 · Answer 1 · edited May 23 '17 at 12:15

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Already answered here : Android : Converting imageview to bitmap, to grayscale, bitmap to imageview

public Bitmap toGrayscale(Bitmap bmpOriginal){        
        int width, height;
        height = bmpOriginal.getHeight();
        width = bmpOriginal.getWidth();    

        Bitmap bmpGrayscale = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
        Canvas c = new Canvas(bmpGrayscale);
        Paint paint = new Paint();
        ColorMatrix cm = new ColorMatrix();
        cm.setSaturation(0);
        ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
        paint.setColorFilter(f);
        c.drawBitmap(bmpOriginal, 0, 0, paint);
        return bmpGrayscale;
    }

edited May 23 '17 at 12:15

Community

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answered Mar 25 '15 at 15:57

NSimon

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in these cases, you can flag the question as a duplicate. – kiranpradeep Mar 25 '15 at 15:59
I can't yet unfortunately :/ – NSimon Mar 25 '15 at 16:01
@kiran sorry for duplicate. but it is the same code either the image from gallery or from drawable? – user4668241 Mar 25 '15 at 16:15
Just get the drawable from the gallery, and pass it through toGrayscale func – NSimon Mar 25 '15 at 16:19
@user4668241 it is not same. But at the moment, the question shows no effort on your part. StackOverflow users might expect some code or any thing which reflects your effort. – kiranpradeep Mar 25 '15 at 16:20

Image from gallery convert to grayscale by click on button (Android)

1 Answers1