Converting an image captured by camera to grayscale

by Sharmila » Thu, 09 Jul 2009 06:22:41 GMT

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 Hi guys,
I have a camera application that captures a 640x480 image.I want to
convert this image to grayscale.I know I have to use the setSaturatio
(float sat) in the ColorMatrix method to zero but I dnt know how I can
set it to grayscale...
Can someone please help me out?

Converting an image captured by camera to grayscale

by Jack Ha » Thu, 09 Jul 2009 07:39:23 GMT

 You can try something like the following:

    Bitmap grayscaleBitmap = Bitmap.createBitmap(
        colorBitmap.getWidth(), colorBitmap.getHeight(),
    Canvas c = new Canvas(grayscaleBitmap);
    Paint p = new Paint();
    ColorMatrix cm = new ColorMatrix();
    ColorMatrixColorFilter cmcf = new ColorMatrixColorFilter(cm);
    c.drawBitmap(colorBitmap, 0, 0, p);

Jack Ha
Open Source Development Center
obilestick together

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