if (mResource != 0) {
            try {
                d = mContext.getDrawable(mResource);
            } catch (Exception e) {
                Log.w(LOG_TAG, "Unable to find resource: " + mResource, e);
                // Don't try again.
                mResource = 0;
            }
        }

//First set your original image tag...
ImageView original; //The original ImageVew
Integer resId = R.drawable.resource; //The original resource
original.setTag(resId); //Add your resource id to the tag

//Then, to get the resource id...
Integer resId = original.getTag();