Android, how to reduce the size of a bitmap?

Question

I have an app that allows the user to change their profile image to another one that is stored on their device. For this, the app sends the selected image to a remote server. All this works well, so I do not put the code of that part so as not to complicate the question. My problem is that I want that bitmap sent to the server is reduced in size to prevent, for example, large files of five or six megabytes, which slow down the app. But it does not end well.

This is my code for this:

if (requestCode == 1 && resultCode == RESULT_OK) {

            Uri selectedImageUri = data.getData();
            imagepath = getPath(selectedImageUri);
            Bitmap bitmap=BitmapFactory.decodeFile(imagepath);

            ByteArrayOutputStream bytearrayoutputstream = new ByteArrayOutputStream();

            //Resize the bitmap
            Bitmap resizedBitmap = Bitmap.createScaledBitmap(bitmap, 150, 150, false);

            resizedBitmap.compress(Bitmap.CompressFormat.JPEG,50,bytearrayoutputstream);


            //Round the image
            int min = Math.min(resizedBitmap.getWidth(), resizedBitmap.getHeight());

            Bitmap bitmapRounded = Bitmap.createBitmap(min, min, resizedBitmap.getConfig());

            Canvas canvas = new Canvas(bitmapRounded);
            Paint paint = new Paint();
            paint.setAntiAlias(true);
            paint.setShader(new BitmapShader(resizedBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
            canvas.drawRoundRect((new RectF(0.0f, 0.0f, min, min)), min / 2, min / 2, paint);

            //bitmap to imageView
            avatar.setImageBitmap(bitmapRounded);

}

I trying to reduce it in size (it does not work) and then round the image (this works fine) before adjusting it to the corresponding ImageView.

The only thing that I can not get it to work properly is to reduce the size of the bitmap.

score 1 · Answer 1 · answered Apr 16 '19 at 11:00

1

i am using this to reduce my bitmap size and it is woring fine :-

ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 40, baos);

answered Apr 16 '19 at 11:00

Sandeep Malik

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1
8
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score 0 · Answer 2 · answered Apr 16 '19 at 11:11

If you want to make your image smaller, you need to first get the height and width of your bitmap, calculate the ratio and then can create a scaled bitmap.

int width = image.getWidth();
int height = image.getHeight();

You have to calculate the image size and return the scaled bitmap.

Find a similar question asked in here: Reduce the size of a bitmap to a specified size in Android

Hope you will get the exact solution.

score 0 · Answer 3 · edited Apr 16 '19 at 11:49

I'm using this helper class.

public class ScaleFile {
    private Context mContext;

    public ScaleFile(Context context) {
        this.mContext = context;
    }

    public Bitmap scaleFile(String imageUri) {

        String filePath = getRealPathFromURI(imageUri);
        Bitmap scaledBitmap = null;
        BitmapFactory.Options options = new BitmapFactory.Options();


        options.inJustDecodeBounds = true;
        Bitmap bmp = BitmapFactory.decodeFile(filePath, options);

        int actualHeight = options.outHeight;
        int actualWidth = options.outWidth;

         //max Height and width values of the compressed image is taken as 816x612

        float maxHeight = 816.0f;
        float maxWidth = 612.0f;
        float imgRatio = actualWidth / actualHeight;
        float maxRatio = maxWidth / maxHeight;

        //width and height values are set maintaining the aspect ratio of the image

        if (actualHeight > maxHeight || actualWidth > maxWidth) {
            if (imgRatio < maxRatio) {
                imgRatio = maxHeight / actualHeight;
                actualWidth = (int) (imgRatio * actualWidth);
                actualHeight = (int) maxHeight;
            } else if (imgRatio > maxRatio) {
                imgRatio = maxWidth / actualWidth;
                actualHeight = (int) (imgRatio * actualHeight);
                actualWidth = (int) maxWidth;
            } else {
                actualHeight = (int) maxHeight;
                actualWidth = (int) maxWidth;

            }
        }

    //setting inSampleSize value allows to load a scaled down version of the original image

        options.inSampleSize = calculateInSampleSize(options, actualWidth, actualHeight);


        options.inPurgeable = true;
        options.inInputShareable = true;
        options.inTempStorage = new byte[16 * 1024];

        try {
            //load the bitmap from its path
            bmp = BitmapFactory.decodeFile(filePath, options);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();

        }
        try {
            scaledBitmap = Bitmap.createBitmap(actualWidth, actualHeight, Bitmap.Config.ARGB_8888);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();
        }

        float ratioX = actualWidth / (float) options.outWidth;
        float ratioY = actualHeight / (float) options.outHeight;
        float middleX = actualWidth / 2.0f;
        float middleY = actualHeight / 2.0f;

        Matrix scaleMatrix = new Matrix();
        scaleMatrix.setScale(ratioX, ratioY, middleX, middleY);

        Canvas canvas = new Canvas(scaledBitmap);
        canvas.setMatrix(scaleMatrix);
        canvas.drawBitmap(bmp, middleX - bmp.getWidth() / 2, middleY - bmp.getHeight() / 2, new Paint(Paint.FILTER_BITMAP_FLAG));

         // check the rotation of the image and display it properly
        ExifInterface exif;
        try {
            exif = new ExifInterface(filePath);

            int orientation = exif.getAttributeInt(
                    ExifInterface.TAG_ORIENTATION, 0);
            Matrix matrix = new Matrix();
            if (orientation == 6) {
                matrix.postRotate(90);
            } else if (orientation == 3) {
                matrix.postRotate(180);
            } else if (orientation == 8) {
                matrix.postRotate(270);
            }
            scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(),
                    scaledBitmap.getHeight(), matrix, true);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return scaledBitmap;
    }

    private String getRealPathFromURI(String contentURI) {
        Uri contentUri = Uri.parse(contentURI);
        Cursor cursor = mContext.getContentResolver().query(contentUri, null, null, null, null);
        if (cursor == null) {
            return contentUri.getPath();
        } else {
            cursor.moveToFirst();
            int index = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            return cursor.getString(index);
        }
    }

    public int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {
            final int heightRatio = Math.round((float) height / (float) reqHeight);
            final int widthRatio = Math.round((float) width / (float) reqWidth);
            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
        }
        final float totalPixels = width * height;
        final float totalReqPixelsCap = reqWidth * reqHeight * 2;
        while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap) {
            inSampleSize++;
        }

        return inSampleSize;
    }

}

score 0 · Answer 4 · answered Sep 15 '21 at 06:29

This is a useful code for you.

/**
 * reduces the size of the image
 * @param image
 * @param maxSize
 * @return
 */
public Bitmap getResizedBitmap(Bitmap image, int maxSize) {
    int width = image.getWidth();
    int height = image.getHeight();

    float bitmapRatio = (float)width / (float) height;
    if (bitmapRatio > 1) {
        width = maxSize;
        height = (int) (width / bitmapRatio);
    } else {
        height = maxSize;
        width = (int) (height * bitmapRatio);
    }
    return Bitmap.createScaledBitmap(image, width, height, true);
}

Bitmap converetdImage = getResizedBitmap(selectedImageUri, 500);

You can refer to it from the following URL. Reduce the size of a bitmap to a specified size in Android

score -1 · Answer 5 · edited Apr 16 '19 at 11:48

-1

Try this:

ByteArrayOutputStream ostream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 80, ostream);

edited Apr 16 '19 at 11:48

Zoe

27,060
21
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148

answered Apr 16 '19 at 11:14

Alok Singh

640
4
14

Unfortunately there is some limitations around this solution. If the source is a PNG file it does not do anything at all. Also, if the CompressFormat is set to PNG, the compression won't do anything to the bitmap – Cavaleiro Jun 06 '20 at 13:00

Android, how to reduce the size of a bitmap?

5 Answers5