Question

How to get thumbnails from sdcard with the given URI ??
I have tried using bitmapfactory but the performance is bad or OutOfMemoryError
I am going to put the thumbnails to the listview with a lot of data
should I use thumbnails or any suggestions?
if thumbnails are to be used then how to do it…?

Thanks in advance for the help

Answer 1

The following method can be used to get the thumbnail of image:

private Bitmap getBitmap(String path) {

    Uri uri = getImageUri(path);
    InputStream in = null;
    try {
        final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
        in = mContentResolver.openInputStream(uri);

        // Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(in, null, o);
        in.close();



        int scale = 1;
        while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) > IMAGE_MAX_SIZE) {
            scale++;
        }
        Log.d(TAG, "scale = " + scale + ", orig-width: " + o.outWidth       + ", orig-height: " + o.outHeight);

        Bitmap b = null;
        in = mContentResolver.openInputStream(uri);
        if (scale > 1) {
            scale--;
            // scale to max possible inSampleSize that still yields an image
            // larger than target
            o = new BitmapFactory.Options();
            o.inSampleSize = scale;
            b = BitmapFactory.decodeStream(in, null, o);

            // resize to desired dimensions
            int height = b.getHeight();
            int width = b.getWidth();
            Log.d(TAG, "1th scale operation dimenions - width: " + width    + ", height: " + height);

            double y = Math.sqrt(IMAGE_MAX_SIZE
                    / (((double) width) / height));
            double x = (y / height) * width;

            Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x,     (int) y, true);
            b.recycle();
            b = scaledBitmap;

            System.gc();
        } else {
            b = BitmapFactory.decodeStream(in);
        }
        in.close();

        Log.d(TAG, "bitmap size - width: " +b.getWidth() + ", height: " + b.getHeight());
        return b;
    } catch (IOException e) {
        Log.e(TAG, e.getMessage(),e);
        return null;
    }
}

And always call bitmap.recycle() method after using bitmaps. It will clear the bitmap from memory. Also avoid memory leaks in your code. This will solve your OOME.