Due to the improvement in people's standards of living, obesity rates are increasing at an alarming speed, and this is reflective of the risks in people's health. People need to control their daily calorie intake by eating healthier foods, which is the most basic method to avoid obesity. However, although food packaging comes with nutrition (and calorie) labels, it's still not very convenient for people to reference. In most of the calorie estimation, the estimated calories are just associated with the estimated food categories and these applications often require users to enter information such as size or volume, there are problems that it is a troublesome and subjective evaluation. Currently, no applications which can estimate food calories automatically exist.