Android : CreateScaledBitmap causing Grow heap

new to Android there is something i really do to understand with bitmap.

I use a custom camera which i open on a Handler thread to take photo on my jpeg callback i want to store my picture in cache after scaling down the picture so the pictures fits in a 1000 x 1000 size keeping its ratio.

To do so i take the picture from the jpeg callback using :

private Camera.PictureCallback jpegCallback = new Camera.PictureCallback() {
    public void onPictureTaken(byte[] data, final Camera camera) {

        Bitmap realImage;
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inSampleSize = 4;
        options.inPurgeable=true;                  
        options.inInputShareable=true;          
        realImage = BitmapFactory.decodeByteArray(data,0,data.length,options);

So far so good, i can take as many pictures as i want, no memory problem...

But when i want to write the picture to cache i need to scaled it down using :

private class addThumbnailASYNC extends AsyncTask<Bitmap, Void, Bitmap> {
    @Override
    protected Bitmap doInBackground(Bitmap... bitmap) {

        Bitmap image = bitmap[0]; 
        int width = image.getWidth();
        int height = image.getHeight();

        float bitmapRatio = (float)width / (float) height;
        if (bitmapRatio > 0) {
            width = MAX_SIZE_IMAGE;
            height = (int) (width / bitmapRatio);
        } else {
            height = MAX_SIZE_IMAGE;
            width = (int) (height * bitmapRatio);
        }

        image = Bitmap.createScaledBitmap(image, width, height, true);  

the problem is when i use image = Bitmap.createScaledBitmap I get a Grow heap which i think will lead to an out of memory if i take many picture.

There are 3 things that i do understand : - When i use options.inSampleSize the picture should be scaled by 4 so why createScaledBitmap causes a grow heap ? - If i do not use createScaledBitmap and that i write the image to cache i never get the grow heap why ? The inSampleSize should gave me more heavy file than the one i create using scaledBitmap ? - I need to avoid memory heap, but how to avoid grow heap because i have no choice using createdScaledBitmap and my picture will be always taken by the camera, i feel stuck.

Thank you for any help, any clues or more ...