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android - BitmapFactory.decodeStream out of memory despite using reduced sample size

I have read many related posts concerning memory allocation problems with decoding bitmaps, but am still unable to find the solution to the following problem even after using the code provided in the official website.

Here is my code:

public static Bitmap decodeSampledBitmapFromResource(InputStream inputStream, int reqWidth, int reqHeight) {

    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    byte[] buffer = new byte[1024];
    int len;
    try {
        while ((len = inputStream.read(buffer)) > -1) {
        baos.write(buffer, 0, len);
        }
        baos.flush();
        InputStream is1 = new ByteArrayInputStream(baos.toByteArray());
        InputStream is2 = new ByteArrayInputStream(baos.toByteArray());

        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(is1, null, options);

        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        options.inPurgeable = true;
        options.inInputShareable = true;
        options.inJustDecodeBounds = false;
        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
        return BitmapFactory.decodeStream(is2, null, options);

    } catch (Exception e) {
        e.printStackTrace();

        return null;
    }
}

public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {

        // Calculate ratios of height and width to requested height and width
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will guarantee
        // a final image with both dimensions larger than or equal to the
        // requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }


    return inSampleSize;
}

bitmap = decodeSampledBitmapFromResource(inputStream, 600, 600); 

I am getting "Out of memory error on a 3250016 - byte allocation" in this line:

return BitmapFactory.decodeStream(is2, null, options);

It would seem to me that 3.2 MB is small enough to be allocated. Where am I going wrong? How can I solve this?

EDIT

After looking into this solution HERE by N-Joy it works fine with Required size 300 but my required size is 800, so i am still getting the error.

See Question&Answers more detail:os

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The method decodeSampledBitmapFromResource is not memory efficient because it uses 3 streams: the ByteArrayOutputStream baos, ByteArrayInputStream is1 and ByteArrayInputStream is2, each of those stores the same stream data of the image (one byte array for each).

And when I test with my device (LG nexus 4) to decode an 2560x1600 image on SDcard to target size 800 it takes something like this:

03-13 15:47:52.557: E/DecodeBitmap(11177): dalvikPss (beginning) = 1780
03-13 15:47:53.157: E/DecodeBitmap(11177): dalvikPss (decoding) = 26393
03-13 15:47:53.548: E/DecodeBitmap(11177): dalvikPss (after all) = 30401 time = 999

We can see: too much memory allocated (28.5 MB) just to decode 4096000 a pixel image.

Solution: we read the InputStream and store the data directly into one byte array and use this byte array for the rest work.
Sample code:

public Bitmap decodeSampledBitmapFromResourceMemOpt(
            InputStream inputStream, int reqWidth, int reqHeight) {

        byte[] byteArr = new byte[0];
        byte[] buffer = new byte[1024];
        int len;
        int count = 0;

        try {
            while ((len = inputStream.read(buffer)) > -1) {
                if (len != 0) {
                    if (count + len > byteArr.length) {
                        byte[] newbuf = new byte[(count + len) * 2];
                        System.arraycopy(byteArr, 0, newbuf, 0, count);
                        byteArr = newbuf;
                    }

                    System.arraycopy(buffer, 0, byteArr, count, len);
                    count += len;
                }
            }

            final BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeByteArray(byteArr, 0, count, options);

            options.inSampleSize = calculateInSampleSize(options, reqWidth,
                    reqHeight);
            options.inPurgeable = true;
            options.inInputShareable = true;
            options.inJustDecodeBounds = false;
            options.inPreferredConfig = Bitmap.Config.ARGB_8888;

            int[] pids = { android.os.Process.myPid() };
            MemoryInfo myMemInfo = mAM.getProcessMemoryInfo(pids)[0];
            Log.e(TAG, "dalvikPss (decoding) = " + myMemInfo.dalvikPss);

            return BitmapFactory.decodeByteArray(byteArr, 0, count, options);

        } catch (Exception e) {
            e.printStackTrace();

            return null;
        }
    }

The method that does the calculation:

public void onButtonClicked(View v) {
        int[] pids = { android.os.Process.myPid() };
        MemoryInfo myMemInfo = mAM.getProcessMemoryInfo(pids)[0];
        Log.e(TAG, "dalvikPss (beginning) = " + myMemInfo.dalvikPss);

        long startTime = System.currentTimeMillis();

        FileInputStream inputStream;
        String filePath = Environment.getExternalStorageDirectory()
                .getAbsolutePath() + "/test2.png";
        File file = new File(filePath);
        try {
            inputStream = new FileInputStream(file);
//          mBitmap = decodeSampledBitmapFromResource(inputStream, 800, 800);
            mBitmap = decodeSampledBitmapFromResourceMemOpt(inputStream, 800,
                    800);
            ImageView imageView = (ImageView) findViewById(R.id.image);
            imageView.setImageBitmap(mBitmap);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        myMemInfo = mAM.getProcessMemoryInfo(pids)[0];
        Log.e(TAG, "dalvikPss (after all) = " + myMemInfo.dalvikPss
                + " time = " + (System.currentTimeMillis() - startTime));
    }

And the result:

03-13 16:02:20.373: E/DecodeBitmap(13663): dalvikPss (beginning) = 1823
03-13 16:02:20.923: E/DecodeBitmap(13663): dalvikPss (decoding) = 18414
03-13 16:02:21.294: E/DecodeBitmap(13663): dalvikPss (after all) = 18414 time = 917

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