Develop Reference

Convert ImageView Vector Drawable to Bitmap Android

I take a fingerprint from the user and add white background to it using glide. The issue is I need to get the byte array of that image and I can't get it because the Image being hold into the ImageView is a VectorDrawable. I am unable to convert this back to bitmap and thus to a byte array. I tried using it on a dummy png image like following.
Take any dummy PNG Image
firstIV = findViewById(R.id.firstIV);
secondIV = findViewById(R.id.secondIV);
Bitmap currentBmp = BitmapFactory.decodeResource(getResources(), R.drawable.test_image);
Glide.with(this).load(currentBmp).into(new SimpleTarget<Drawable>() {
#Override
public void onResourceReady(Drawable resource, Transition<? super Drawable> glideAnimation) {
final ShapeDrawable background = new ShapeDrawable();
background.getPaint().setColor(Color.WHITE);
final Drawable[] layers = {background, resource};
firstIV.setImageDrawable(new LayerDrawable(layers));
setToAnotherImageView(firstIV.getDrawable().getIntrinsicWidth(), firstIV.getDrawable().getIntrinsicHeight());
}
});
Applied Solution
private void setToAnotherImageView(int width, int height) {
Log.e(TAG, "onCreate: " + width + ":" + height);
Bitmap convertedBmp = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(convertedBmp);
firstIV.draw(canvas);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
convertedBmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
Bitmap newBmp = BitmapFactory.decodeByteArray(byteArray,0,byteArray.length);
secondIV.setImageBitmap(newBmp);
}
Upon doing so my app crashes with an exception saying the vector drawable can not be converted to bitmap. The following is the error:
Originally what I want to achieve
Originally I want the bytearray of the the picture I have stored in my ImageView so I can convert that bytearray to WSQ bytearray and the send it to my server. I am trying to achieve such with an example defined above.

UPDATE:
Just find out that there is a new way to get Bitmap from ImageView:
imageView.drawToBitmap() //draw from the ImageView size
imageView.drawable.toBitmap() //draw from original Drawable size (I guess)
Convert ImageView to ByteArray:
private fun getImageBytes(): ByteArray {
val bitmap = Bitmap.createBitmap(my_profile_imageView.width, my_profile_imageView.height, Bitmap.Config.ARGB_8888)
val canvas = Canvas(bitmap)
my_profile_imageView.draw(canvas)
val outputStream = ByteArrayOutputStream()
bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream)
return outputStream.toByteArray()
}
However, it's not a good idea to store the image ByetArray in local, you should store the uri or url instead.

My question is a duplicate of How to get a Bitmap from VectorDrawable
However I solved it like this
private void setToAnotherImageView() {
Drawable drawable = firstIV.getDrawable();
Bitmap newBmp = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(newBmp);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
secondIV.setImageBitmap(newBmp);
}

How to capture screenshot with zoomed out webview?

I have a webview with built in zoom-controls how to capture screenshot with full zoomed out webview and how to implement custom zoom in and out button.

To get View's drawing cache you can use this code:
public static Bitmap getBitmapFromView(View view) {
Bitmap bmp = Bitmap.createBitmap(view.getLayoutParams().width, view.getLayoutParams().height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bmp);
view.layout(0, 0, view.getLayoutParams().width, view.getLayoutParams().height);
view.draw(canvas);
return bmp;
}
Then convert bitmap to PNG/JPG:
OutputStream stream = new FileOutputStream("/sdcard/test.png");
bitmap.compress(CompressFormat.PNG, 100, stream);
stream.close();
This should work.

OutOfMemoryException when using large images

I tried to post an image on Facebook wall from my android application.For this I created a bitmap from layout.Here is my code
System.gc();
Bitmap bitmap = Bitmap.createBitmap(
view.getMeasuredWidth(),
view.getMeasuredHeight(),
Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
Drawable bgDrawable = newLinearLayout.getBackground();
if (bgDrawable != null)
bgDrawable.draw(canvas);
else
canvas.drawColor(Color.WHITE);
view.draw(canvas);
Matrix matrix = new Matrix();
// resize the bit map
matrix.postScale(1.0f, 1.0f);
// recreate the new Bitmap
Bitmap resizedBitmap = null;
resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0,
bitmap.getWidth(), bitmap.getHeight(), matrix, true);
//Canvas resizedCanvas = new Canvas(resizedBitmap);
if (bitmap != null) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
resizedBitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
Bundle parameters = new Bundle();
byte[] data = baos.toByteArray();
parameters.putByteArray("picture", data);
DataKeeper.getInstance().setBundleToPost(parameters);
}
bitmap.recycle();
It shows OutOfMemory exception.I know that this is due to imagesize exceeds its available size.How can i resize image without lossing its quality? I tried to correct this using BitmapFactory.Options. But does not work.How can solve this exception?
Regards
Asha

use this :
BitmapFactory.Options options=new BitmapFactory.Options();
options.inSampleSize = 8;
Bitmap preview_bitmap=BitmapFactory.decodeStream(is,null,options);
for more detail see this link
link

The idea of #Zaz Gmy is correct,
however I don't think the value of inSampleSize should be constant (8) for every image.
This of course will work, but scaling different images with different resolutions on the same scale factor = 8, will cause some of images to have a visible loss of quality.
Instead, the inSimpleSize should be generated based on the target width and height of image.
Android documentation provides a good article on how to deal with this issue.

Please check this tutorial and download the sample project.This will solve your problem
http://developer.sonymobile.com/wp/2011/06/27/how-to-scale-images-for-your-android%E2%84%A2-application/

How to read drawable bits as InputStream

There's say some ImageView object. I want to read bits/raw data of this object as InputStream. How to do that?

First get background image of the ImageView as an object of Drawable:
iv.getBackground();
Then convert Drawable image into Bitmap using
BitmapDrawable bitDw = ((BitmapDrawable) d);
Bitmap bitmap = bitDw.getBitmap();
Now use ByteArrayOutputStream to get the Bitmap into a Stream and get bytearray[]; then
convert the bytearray into a ByteArrayInputStream.
You can use the following code to get InputStream from ImageView.
Full Source code
ImageView iv = (ImageView) findViewById(R.id.splashImageView);
Drawable d = iv.getBackground();
BitmapDrawable bitDw = ((BitmapDrawable) d);
Bitmap bitmap = bitDw.getBitmap();
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream);
byte[] imageInByte = stream.toByteArray();
System.out.println("........length......" + imageInByte);
ByteArrayInputStream bis = new ByteArrayInputStream(imageInByte);
Thanks
Deepak

These methods below are useful because they work with any kind of Drawable (not only BitmapDrawable). If you want to use drawing cache as in David Caunt's suggestion, consider using bitmapToInputStream instead of bitmap.compress, because it should be faster.
public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}
Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
public static InputStream bitmapToInputStream(Bitmap bitmap) {
int size = bitmap.getHeight() * bitmap.getRowBytes();
ByteBuffer buffer = ByteBuffer.allocate(size);
bitmap.copyPixelsToBuffer(buffer);
return new ByteArrayInputStream(buffer.array());
}

You can use the drawing cache to retrieve a Bitmap representation of any View class.
view.setDrawingCacheEnabled(true);
Bitmap b = view.getDrawingCache();
Then you can write the bitmap to an OutputStream, for example:
b.compress(CompressFormat.JPEG, 80, new FileOutputStream("/view.jpg"));
In your case I think you can use a ByteArrayOutputStream to get a byte[] from which you can create an InputStream. The code would be something like this:
ByteArrayOutputStream os = new ByteArrayOutputStream(b.getByteCount());
b.compress(CompressFormat.JPEG, 80, os);
byte[] bytes = os.toByteArray();

You might be looking for this:
openRawResource

Bitmap.compress returns false for drawn image

I have some code where the user draws something on the screen and I want to store it as a PNG in a byte[]. However, the compress() method returns false. Any idea why that is? Is there a better way to get the byte[]?
Bitmap bm = Bitmap.createBitmap(mWidth, mHeight, Bitmap.Config.ALPHA_8);
Canvas c = new Canvas(bm);
c.drawPath(mSignaturePath, mSignaturePaint);
ByteArrayOutputStream out = new ByteArrayOutputStream();
if (bm.compress(Bitmap.CompressFormat.PNG, 100, out)) {
byte[] result = out.toByteArray(); // Never gets called
}
Thanks in advance.

The problem was in how I was creating the image:
Bitmap bm = Bitmap.createBitmap(mWidth, mHeight, Bitmap.Config.ALPHA_8);
When I changed that to Bitmap.Config.RGB_565 it worked fine.
Thanks to Mark Murphy (#commonsware) for the advice during his office hours!