Android Capturing Images from Camera or Gallery as Bitmaps

5 min readMar 6, 2021

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Capturing images using a camera and using it in your Android applications can be tricky at times but the process is quite simple.

So in this story, I will teach you to get images from the gallery or capture images using a camera and then getting those images as bitmaps in our applications.

So firstly create a new Android studio project and select Java as the programming language. For Kotlin click here.

Layout

Now in the activity_main.xml file place an ImageView widget

<ImageView
    android:id="@+id/imageView"
    android:layout_width="0dp"
    android:layout_height="0dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.0"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    app:layout_constraintVertical_bias="0.326"
    app:srcCompat="@android:drawable/alert_dark_frame" />

Now inside MainActivity create and initialize this imageview.

public class MainActivity extends AppCompatActivity {

    ImageView imageView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imageView = findViewById(R.id.imageView);
    }
}

Permissions

As we want to capture images from the camera so we need the camera permission and then to save those images we need storage permission so in the manifest file add these lines

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.CAMERA"/>

Ask for these permissions dynamically inside MainActivity. So add these lines inside the onCreate method of MainActivity.

//TODO ask for permission of camera upon first launch of application
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    if (checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_DENIED || checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)
            == PackageManager.PERMISSION_DENIED){
        String[] permission = {Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE};
        requestPermissions(permission, 112);
    }
}

Capturing image using camera

Let’s say when the user will long press on the imageView we want to open the camera and capture the image. Then we want to display that captured image inside our Android application.

So to achieve that set OnLongClickListener on the imageView. So inside onCreate method paste the below code.

//TODO captue image using camera
imageView.setOnLongClickListener(new View.OnLongClickListener() {
    @Override
    public boolean onLongClick(View v) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
            if (checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_DENIED || checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    == PackageManager.PERMISSION_DENIED){
                String[] permission = {Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE};
                requestPermissions(permission, PERMISSION_CODE);
            }
            else {
                openCamera();
            }
        }

        else {
            openCamera();
        }
        return false;
    }
});

So inside this method, we are again checking if the camera and storage permission is granted or not. If the permission is not granted then we are asking for permission again otherwise we are calling a method name openCamera. Inside this method, we have the code to launch the camera. So place this code below onCreate method.

Uri image_uri;
private static final int RESULT_LOAD_IMAGE = 123;
public static final int IMAGE_CAPTURE_CODE = 654;
//TODO opens camera so that user can capture image
private void openCamera() {
    ContentValues values = new ContentValues();
    values.put(MediaStore.Images.Media.TITLE, "New Picture");
    values.put(MediaStore.Images.Media.DESCRIPTION, "From the Camera");
    image_uri = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
    Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, image_uri);
    startActivityForResult(cameraIntent, IMAGE_CAPTURE_CODE);
}

Now inside this method, we are launching an intent to open the camera, and once the user will capture the image then the URI of that image will be stored inside the image_uri variable. But to ensure that the user has captured the image we will add the onActivityResult method and check if image an image was captured or not. So add this method below openCamera method.

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    
    if (requestCode == IMAGE_CAPTURE_CODE && resultCode == RESULT_OK){
        innerImage.setImageURI(image_uri);
    }
}

Converting Image into bitmap

Now we have the captured image URI and we are displaying that image inside the image view. But to get the image in a bitmap format place this uriToBitmap method inside MainActivity

//TODO takes URI of the image and returns bitmap
private Bitmap uriToBitmap(Uri selectedFileUri) {
    try {
        ParcelFileDescriptor parcelFileDescriptor =
                getContentResolver().openFileDescriptor(selectedFileUri, "r");
        FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
        Bitmap image = BitmapFactory.decodeFileDescriptor(fileDescriptor);

        parcelFileDescriptor.close();
        return image;
    } catch (IOException e) {
        e.printStackTrace();
    }
    return  null;
}

Now call this method inside onActivityResult and pass the image uri to get that image in a bitmap format.

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == IMAGE_CAPTURE_CODE && resultCode == RESULT_OK){
        //imageView.setImageURI(image_uri);
        Bitmap bitmap = uriToBitmap(image_uri);
        imageView.setImageBitmap(bitmap);
    }
}

And that’s it. Now when you will run this application you will be able to capture an image from the camera and then that image will be displayed inside imageview. As we also converted that image into a bitmap so you can use it for a variety of different purposes.

Choosing Images from gallery

Let’s say we want to choose the image from the gallery when the user will click on the image view that we placed earlier inside our application layout.

So inside onCreate method set OnClick listener for the image view.

//TODO chose image from gallery
imageView.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Intent galleryIntent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(galleryIntent, RESULT_LOAD_IMAGE);
    }
});

Now there you can see when the user will click on the imageview we are launching an intent to open the gallery. And once the user will select an image onActivityResult method will be called and we can get the URI of the selected image inside that method. So add this code inside onActivityResult method

Uri image_uri;
private static final int RESULT_LOAD_IMAGE = 123;
public static final int IMAGE_CAPTURE_CODE = 654;
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && data != null){
        image_uri = data.getData();
        imageView.setImageURI(image_uri);
    }
}

So inside this method, we are getting chosen image Uri and displaying that image inside our image view.

Now when you will run this application you will be able to choose an image from the gallery as well.

Converting Image into bitmap

Now we have the Uri of the image and if you want to get the image as Bitmap So call the uriToBitmap method again. So the code inside onActivityResult will be

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == IMAGE_CAPTURE_CODE && resultCode == RESULT_OK){
        //imageView.setImageURI(image_uri);
        Bitmap bitmap = uriToBitmap(image_uri);
        imageView.setImageBitmap(bitmap);
    }


    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && data != null){
        image_uri = data.getData();
        //imageView.setImageURI(image_uri);
        Bitmap bitmap = uriToBitmap(image_uri);
        imageView.setImageBitmap(bitmap);
    }

And that’s it, now you can run the application and test it. You can also get the application code from Github.

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Learn the use of machine learning and computer vision in Android, Flutter & React Native with our Mobile Machine Learning courses. You can avail discount on the following Mobile Machine learning courses