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@moondroid
Created March 12, 2015 09:15
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Transform Bitmap to grayscale
public static Bitmap toGrayScale(Bitmap bmpOriginal) {
int width, height;
height = bmpOriginal.getHeight();
width = bmpOriginal.getWidth();
Bitmap bmpGrayscale = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
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);
bmpOriginal.recycle();
return bmpGrayscale;
}
@arifbd
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arifbd commented Jun 10, 2018

I use your method, but i got this error on (Samsung Galaxy Grand Prime, 1024MB RAM, Android 5.0) and (Samsung Galaxy J7, 1536MB RAM, Android 6.0)

java.lang.OutOfMemoryError:
...
...
...
at packageName.toGrayscale (Conversions.java:32)
...
...
...

the code of 32 no lines are given below.
Bitmap bmpGrayscale = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);

please help me. Thank you in advance!

@rayworks
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rayworks commented Aug 9, 2018

@arifbd
It seems the original bitmap is quite large. Please check the width and height before you call the method Bitmap.createBitmap(...).

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