The rapid development of mobile devices capable of sensing our interaction with the environment has make it possible to assist humans in daily living such as helping patients with cognitive impairment or providing customized food intake plan for patients with obesity, etc. All of this can be achieved through the passive gathering of detailed records of everyday behaviour which is termed as lifelogging. For example, the widely adopted smart mobiles and newly-emerging consumer wearable devices like Google glass, Baidu eye, Narrative clip, etc. are usually embedded with rich sensing capabilities including camera, accelerometer, GPS, digital compass, etc. which can help to capture daily activity unobtrusively. Among such heterogeneous sensor re...