Develop Reference

How do I save the viewport bitmap of an imageview? - Android

I only want to save the bitmap of the image being displayed/cropped in the ImageView.
When I call this, it returns the entire bitmap:
Bitmap bitmap = ((BitmapDrawable) imageView.getDrawable()).getBitmap();

Use this to get the bitmap from ImageView
imageView.buildDrawingCache();
Bitmap bmap = imageView.getDrawingCache();

Can't get bitmap from drawable

I have used the code below to get bitmap, but I am getting only half of the image has been showing.
Bitmap bm = BitmapFactory.decodeResource(context.getResources(),R.drawable.ca_buyingpower);

How to get the whole bitmap attached to an ImageView?

I tried to get Bitmap attached to an ImageView, using ImageView.getDrawingCache(); But I found that the returned Bitmap was not the same as I'd like to get from the ImageView. It was always smaller than the real image.
I had known that, the method getDrawingCache() should not have the view if it is bigger than the screen as the visible portion of the view is only drawn and the cache holds only what is drawn.
Could I get the whole bitmap attached to a ImageView?

If you just want the Bitmap from a ImageView the following code may work for you:-
Bitmap bm=((BitmapDrawable)imageView.getDrawable()).getBitmap();
I think that's what you wanted.

If your drawble is not always an instanceof BitmapDrawable
Note: ImageView should be set before you do this.
Bitmap bitmap;
if (mImageView.getDrawable() instanceof BitmapDrawable) {
bitmap = ((BitmapDrawable) mImageView.getDrawable()).getBitmap();
} else {
Drawable d = mImageView.getDrawable();
bitmap = Bitmap.createBitmap(d.getIntrinsicWidth(), d.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
d.draw(canvas);
}
Your bitmap is stored in bitmap.
Voila!

Easiest way is to set tag in ImageView.
imageView.setImageBitmap(bitmap);
imageView.setTag(bitmap);
To get Tag from it
imageView.getTag();

Bizarre ImageView Bitmap Handling

I've encountered totally bizarre behavior in the way Android loads bitmaps into ImageView. For example, I have a 500x313 image file called urimg_01.jpg. With this code:
img.setImageResource(R.drawable.urimg_01);
Bitmap bitmap = ((BitmapDrawable) img.getDrawable()).getBitmap();
Log.v(TAG,"---------------------> bitmap width = "+bitmap.getWidth());
Log.v(TAG,"---------------------> bitmap height = "+bitmap.getHeight());
the ImageView bitmap is 750x470. (I have a Nexus S with 480x800 display.)
With this code, which reads a copy of the same file located in getFilesDir():
Log.v(TAG,"image file is "+filelist[0].getAbsolutePath());
FileInputStream fis = new FileInputStream(filelist[0]);
FileDescriptor fd = fis.getFD();
Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd);
if (bitmap != null) {
Log.v(TAG,"---------------------> bitmap width = "+bitmap.getWidth());
Log.v(TAG,"---------------------> bitmap height = "+bitmap.getHeight());
img.setImageBitmap(bitmap);
fis.close();
}
the ImageView bitmap is 500x313, as expected.
In the case of setImageResource(), where the devil is it getting 750x470 from?? And how do I get it to use the correct dimensions for resources in drawable?

Your resource is being scaled up because it's probably stored in a medium density folder and you're using a high density device. See Bitmap getWidth returns wrong value for details.

here you get your bitmap
Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd);
now scale it according to device height and width
Display display=this.getWindowManager().getDefaultDisplay();
int w=display.getWidth();
int h=display.getHeight();
Bitmap newBitmap=Bitmap.createScaledBitmap(oldBitmap, w, h, false);
//now setImage to background with new Bitmap
One important thing "this" should be activity context
:) cheers

image size reduced after editing

i created a new image by combining two images. but the size of the final is image is reduced to the size(resolution) of the screen. the code used is
Bitmap pic = BitmapFactory.decodeResource(getResources(), R.drawable.me);
Bitmap stat= BitmapFactory.decodeResource(getResources(), R.drawable.static);
Bitmap out1 = Bitmap.createBitmap(stat) ;
Canvas comboImage = new Canvas(out1);
comboImage.drawBitmap(map, 0, 0, null);
comboImage.drawBitmap(pic, 150f, 30f, null);
after this i am storing the image as
OutputStream os = null;
os = new FileOutputStream("/sdcard/DCIM/Camera/" + "myNewFileName5.png");
out1.compress(CompressFormat.PNG, 100, os);
os.flush();
os.close();
dimension of image is staic 640x480. but my final image is 320x240, which is my phones screen resolution. is it because i use Canvas? is there any way to do this without changing the image sizes?

Check your API version? There's an explanation at In the onDraw() method, why does the supplied Canvas already have scale? that for an API level lower than 4 the canvas has a default scaled compatibility mode as if it were targeting a G1 screen.