How to load bitmap from res without resizing?

Question

Using this code:

    Drawable blankDrawable = context.getResources().getDrawable(image);
    Bitmap blankBitmap=((BitmapDrawable)blankDrawable).getBitmap();

I get a bitmap that is scaled to the density of the context, preserving the physical size of the bitmap (based on its dpi value). So for example, I have a 405x500 bitmap (dpi=96) as a resource. But when I load it on a device, I get a 608x750 image with density=240. I want to load the bitmap without scaling. How do I do that?

This question is very similar to:

How to create a Drawable from a stream without resizing it?

However, that solution cannot be used in my case, because I don't have an input stream. All I have is a resource id, and the getDrawable() method does not have parameters for density. Once the bitmap is loaded, it is too late - it was already resized.

Thank you.

RajaReddy PolamReddy · Answer 1 · 2014-12-15T11:47:49.877

30

use this

InputStream is = this.getResources().openRawResource(imageId);
Bitmap originalBitmap = BitmapFactory.decodeStream(is);  
imageview.setImageBitmap(originalBitmap);

edited Dec 15 '14 at 11:47

answered Oct 01 '11 at 08:56

RajaReddy PolamReddy

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score 16 · Answer 2 · answered Jun 25 '13 at 06:29

When you're decoding the bitmap with

BitmapFactory.decodeResource (Resources res, int id, BitmapFactory.Options opts)

Set the flag inScaled in BitmapFactory.Options to false first.

Example:

/* Set the options */
Options opts = new Options();
opts.inDither = true;
opts.inPreferredConfig = Bitmap.Config.RGB_565;
opts.inScaled = false; /* Flag for no scalling */ 


/* Load the bitmap with the options */
bitmapImage = BitmapFactory.decodeResource(context.getResources(),
                                           R.drawable.imageName, opts);

Could you explain inDither? I have read the doc, but do not quite understand it. "@deprecated. if dither is true, the decoder will attempt to dither the decoded image." — CoderYel, May 29 '17 at 15:00

score 7 · Answer 3 · answered Jan 24 '14 at 01:23

7

Another good option may be to put the bitmap in the drawable-nodpi resource folder

answered Jan 24 '14 at 01:23

nmr

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score 3 · Accepted Answer · answered Oct 01 '11 at 09:43

3

Create a drawable (without hdpi/mdpi etc) folder in res. Keep the drawable in that folder. Now try it. This may help you.

answered Oct 01 '11 at 09:43

Walid Hossain

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8

Here is another way to do it. Create new folder res/drawable-nodpi and put your image there! It won't be scaled so this will load it with the original size (in pixels): Drawable dh = Context.getResources().getDrawable(R.drawable.your_image_id); Bitmap bh =((BitmapDrawable)dh).getBitmap(); – nagylzs Oct 03 '11 at 10:32

Nikunj Patel · Answer 5 · 2011-10-01T10:13:25.917

2

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ImageView image = (ImageView) findViewById(R.id.test_image);
    Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
    image.setImageBitmap(bMap);
}

First create an ImageView instance containing the ImageView from the layout. Then create a bitmap from the application icon (R.drawable.icon) with BitmapFactory.decodeResource(). Finally set the new bitmap to be the image displayed in the ImageView component of the layout.

edited Oct 01 '11 at 10:13

answered Oct 01 '11 at 08:59

Nikunj Patel

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1

It might work. However, my application directly uses hundreds of bitmaps, and draws on them in-memory. In fact, the method gets the context as a parameter. It is only used to get resources. Otherwise the bitmap is not directly displayed... So I like the InputStream version much better, because it does not use any GUI component. – nagylzs Oct 01 '11 at 16:43

How to load bitmap from res without resizing?

5 Answers5

First create an ImageView instance containing the ImageView from the layout. Then create a bitmap from the application icon (R.drawable.icon) with BitmapFactory.decodeResource(). Finally set the new bitmap to be the image displayed in the ImageView component of the layout.