## 5 Conclusions  
After obtaining the 3D foot model, the user can adjust the selected style of shoe tree and make the feature points, walking and other parts on the shoe tree more comfortable. After the adjustment, the factory can hit the entity shoe tree, then entity shoe tree to footwear processing workshops, producing shoes according to a user's foot type personalization. This method can solve the problem that many customers cannot buy suitable shoes. As one of the applications of the foot model, a shoe tree was built according to the foot model, and different shoe models were designed based on the shoe tree model. It can realize the whole process of digitization and automation [31]. A large number of consumer foot data can be used to build a big enterprise foot database, helping designers to design more personalized and comfortable shoes. At the same time, it can also be used to compare new products with original design data, detect processing accuracy, improve production efficiency and ensure product quality. The 3D model of the foot generated by this method is widely used; it can be used not only for high-end personalized customization, but also for medical and other situations. Here are a few examples:  
Orthopedic shoes custom: Collecting the patient's foot 3D model, producing the orthopedic shoes according to the patient's foot 3D model. At the same time, the orthopedic center can compare the foot model of the patients in different periods and observe the correction. Foot database: The data collection terminal obtains 3D foot data of the consumer with the permission of the consumer, and continuously sends the 3D foot data of the brand audience to the background database. It can easily establish an informative and comprehensive 3D foot database;  
Prosthetic production: Disabled patients have limited mobility, and can use the 3D reconstruction technology based on mobile phone photography to scan the patient's other healthy foot at home, and then get a complete 3D model of the foot quickly. Then we can produce prostheses and also make sure that the two feet are exactly the same;  
Medical diagnosis: Quickly collect 3D data of the patient's foot, and the podiatrist can accurately determine the shape of the patient's foot disease based on the collected 3D data, so as to adopt a more scientific and more effective treatment method;  
Surgical assistance: Using the collected 3D data of the patient's foot, through careful observation of the patient's foot in the computer, the best surgical plan to ensure the success rate of the operation can be designed;  
In addition, the method can also be widely used in other areas to obtain 3D big data of the human body, such as smart wearable devices, medical treatment and health, and so forth. Compared to the foot scanner, this method can reduce the costs of data collection and it does not require professional equipment so it is not limited by the venue; it is also flexible with high portability and good practicability. This method is also suitable for 3D reconstruction of multiple parts in multiple scenes. Next, we will further improve the accuracy of the model by improving the dense reconstruction method and add the 3D model edge line extraction method to extract more foot shape parameters. We also plan to develop an application; this method could be very economically effective for manufacturing and healthcare. Nowadays, the 3D foot scanner can be divided into two types: handheld scanner and stationary scanner. A handheld 3D scanner is flexible, convenient and versatile, suitable for scanning complex structure multi-curved objects. The stationary 3D scanner has high accuracy, which is not affected by object color and light. The price of the scanner varies from 800 $-30,000 $, depending on its use and accuracy, which is expensive for customers. Our application, however, is low-cost and highly flexible; we use the mobile phone as a tool to obtain images, then the reconstruction process is deployed on the cloud.