Research On Image Privacy Protection Protocol Based On Secret Sharing

With the booming of the era of big data,people can use mobile devices to collect a large number of high-quality and multi-type image data.These image data,compared with stored in the hands of a single user,if shared with other users or scientific research institutions in need,would bring immeasurable economic returns and social benefits.In the process of image sharing,a reasonable access strategy must be set for the shared image.Only authorized users can get a shared image,while unauthorized users cannot get the shared image.In order to achieve this goal,image encryption technology is an effective method.However,the traditional image encryption technology has limitations and cannot be applied flexibly in the all-embracing realistic environment,especially in the practical application with the requirements of risk dispersion,loss tolerance,multi-party joint management,lightweight decryption and so on.Image sharing protocol based on secret sharing technology is a feasible solution.Using the image sharing protocol,on the one hand,the shared image can be transformed into a noise-like image before transmission,and on the other hand,a reasonable access strategy can be set for the shared image.According to this method,the shared images in the transmission and stored procedures can be protected.When image sharing has become an important trend of resource sharing in today's society,it need to process shared images and set reasonable access rights from the perspective of practical application requirements.Therefore,in the face of the requirements of different scenes,based on secret sharing technology,this thesis proposes three different image sharing protocols to protect the security and privacy in the process of image sharing.The details are as follows:(1)A multi-threshold progressive image sharing protocol is proposed.In most image sharing protocols,the reconstruction of a shared image requires that participants must collect a sufficient share of the shared image,otherwise,they cannot get any information about the shared image.In this case,the reconstruction of the shared image needs to consume more computing resources and communication resources.Considering that image data is different from other discrete data,image data is highly correlated and retains some availability even in the case of lossy.In order to improve the efficiency of reconstruction,a progressive image sharing protocol can be designed.In this protocol,with the accumulation of shares,participants can gradually obtain images with improved visual quality.In the case that they are not interested in rough data,transmission can be terminated immediately to improve the efficiency of reconstruction.At the same time,this image sharing mode can provide a way to protect the privacy of shared images for those users who enjoy the service of publishing photos on the network.Users can set access policies to control whether other users have download rights to their published images,so as to protect their privacy.(2)An image sharing protocol with essential participants is proposed.The protocol solves the problem of image sharing among devices with different capabilities.It is well known that cloud servers have more computing power and storage capacity than handheld devices.When images are shared between cloud servers and handheld devices,different priorities need to be set for different devices.For example,a cloud server can be defined as an essential participant,while a handheld device can be defined as a non-essential participant.In the process of image sharing,the cloud server can receive and store the essential shadow images with high weight,while the handheld device can store some non-essential shadow images.At the same time,compared to handheld devices,cloud servers need to make a greater contribution to the shared image reconstruction process.Therefore,in the proposed image sharing protocol with essential participants,each device can accomplish the storage and computing tasks by assigning tasks that match the capabilities of different devices.(3)A progressive image sharing protocol with essential participants is proposed.This protocol is a further extension of the progressive image sharing protocol and the image sharing protocol with essential participants.It combines the advantages of the two protocols and can be applied to real applications more flexibly.For example,the proposed protocol can be applied to an image trading platform.The image publisher,the owner of the original image,is mainly responsible for providing high-quality shared images to consumers.Consumers can obtain the right to use shared images by paying a fee to the image publisher.The proposed protocol provides a win-win payment model for both the trading platform and the customer.In this model,customers are allowed to browse low-quality images first to inform them of their purchase.If the customer is interested in a particular image,they can pay for a high-quality image.At the same time,the platform can also adopt a tiered pricing rule for images of different quality.Different quality images correspond to different prices.Customers can choose to buy images of different quality according to their own needs.