How to set bitmap to ARGB_8888 in android?

Question

In my android project, I load a bitmap from a image in the phone. I then do various image manipulations to it like cropping, resizing, editing pixel values.

But the problem is the format of the bitmap is not ARGB_8888, so its not really storing the alpha values. Or rather its always keeping them at 255.

How can I load the bitmap in ARGB_8888 format? This is my code to load and resize. How can I specify the format in any of these?

Thanks

private static Bitmap resize(Bitmap img, int newW, int newH) throws IOException {
    Bitmap resizedImg = Bitmap.createScaledBitmap(img, newW, newH, false);
    img.recycle();

    Bitmap newresizedImg = resizedImg.copy(Bitmap.Config.ARGB_8888, true);
    resizedImg.recycle();


    Pixel initialPixel = Function.getPixel(0, 0, newresizedImg, null);
    int a = initialPixel.getColor().getAlpha(); // -> 255
    newresizedImg.setPixel(0, 0, Pixel.getTransparentColor().getRGB());
    initialPixel = Function.getPixel(0, 0, newresizedImg, null);
    int new_a = initialPixel.getColor().getAlpha(); // -> 255

    return newresizedImg;
}

private static Bitmap getImage(String from) throws IOException {
    File file = new File(from);

    if (file.exists()) {
        BitmapFactory.Options op = new BitmapFactory.Options(); 
        op.inPreferredConfig = Bitmap.Config.ARGB_8888; 
        Bitmap bufferedImage = BitmapFactory.decodeFile(from, op);
        return bufferedImage;
    }
    return null;
}

Pixel class

public static Color getTransparentColor() {
    return new Color(0, 0, 0, 0);
}

Color class

public int getRGB() {
    return ((A << 24) | 0xFF) + ((R << 16) | 0xFF) + ((G << 8) | 0xFF) + (B | 0xFF);
}

score 8 · Answer 1 · answered Aug 29 '14 at 22:13

8

You can copy your bitmap using this type of function (or you know, not use a function depending on how you want to use it)

private Bitmap ARGBBitmap(Bitmap img) {
  return img.copy(Bitmap.Config.ARGB_8888,true);
}

answered Aug 29 '14 at 22:13

Grambot

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What file format you reading into it? I've used code very similar to yours above with great success. What file format? Can you perhaps provide a sample of the image you're having issues with? Have you stepped through the function with a debugger to check all the getPixel functions to make sure they're returning the results you expect? – Grambot Sep 02 '14 at 13:55

score 1 · Answer 2 · edited May 23 '17 at 12:02

1

BitmapFactory.Options op = new BitmapFactory.Options(); op.inPreferredConfig = Bitmap.Config.ARGB_8888; bitmap = BitmapFactory.decodeFile(path, op);

from: How can I specify the bitmap format (e.g. RGBA_8888) with BitmapFactory.decode*()?

edited May 23 '17 at 12:02

Community

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1

answered Aug 29 '14 at 22:13

TehCoder

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I think I lose the Alpha support when I resize it. How can I fix it? – omega Aug 29 '14 at 22:42
It shouldn't lose Alpha 'support' what's the code you used for resizing? – TehCoder Aug 29 '14 at 22:43
Umm stupid me. Well you are creating a new Bitmap which hasn't got that setting yet. – TehCoder Aug 29 '14 at 22:45
How can I specify that setting when I resize it? – omega Aug 29 '14 at 22:45
Isn't there a fourth parameter for a `Bitmap.Config...` when creating the resized image? – TehCoder Aug 29 '14 at 22:48
resizing already takes 4 parameters, if you mean fifth, then I tried it and it doesn't support that. – omega Aug 29 '14 at 22:49
I put code above that gets the alpha from the first pixel, and its 255, then I set it to 0 alpha, and when I get the alpha again, its back to 255. This is after I did the copy command with the alpha support setting. – omega Aug 29 '14 at 22:51
Bitmap convertedBitmap = convert(bitmap, Bitmap.Config.RGB_8888); hmm found this somewhere – TehCoder Aug 29 '14 at 22:52
What class has the convert function? – omega Aug 29 '14 at 22:55
whoops forgot the link :(http://stackoverflow.com/questions/15058905/converting-bitmap-in-memory-to-bitmap-with-bitmap-config-rgb-565 – TehCoder Aug 29 '14 at 22:57

score 1 · Answer 3 · answered May 24 '18 at 12:53

1

Hope this helps as this works for me.

Bitmap bitmap = Bitmap.createBitmap(marker.getMeasuredWidth(), marker.getMeasuredHeight(), Bitmap.Config.ARGB_8888);

answered May 24 '18 at 12:53

AkashToSky

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score 0 · Answer 4 · edited Nov 04 '15 at 02:36

0

You can use this:

public Bitmap highlightImage(Bitmap src) { 
    Bitmap bmOut = Bitmap.createBitmap(src.getWidth() + 96, src.getHeight() + 96, Bitmap.Config.ARGB_8888); 
    return bmOut;
}

edited Nov 04 '15 at 02:36

Pang

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answered Aug 29 '14 at 22:36

Soham

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Why the +96 height and width? – TehCoder Aug 29 '14 at 22:40
Not necessary to use +96. I have use that to scale the image.It's necessity purpose. – Soham Aug 29 '14 at 22:47
Oh it's an example my bad – TehCoder Aug 29 '14 at 22:49

How to set bitmap to ARGB_8888 in android?

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