Rajarathnam Nallusamy

Watermarking video content using visual cryptography and scene averaged image

With the increasing convergence of network, services, and devices, more number of end user devices are accessing digital media content which were hitherto accessible mainly from computers and television sets. This makes the digital media more prone to illegal copying and distribution. In this paper, we propose a robust digital video watermarking scheme for copyright protection using the principles of visual cryptography, scene change detection in videos, and conversion of each scene into an image by averaging the frames in the scene. In the proposed method, data is extracted and stored as one share of the watermark pattern instead of embedding data into the original video as in the conventional watermarking schemes. Since no data is embedded, the method is robust against watermark attacks aimed at detecting and destroying or distorting data embedded into videos. Simulation results show that the method is robust even in the case of 50% frame drop. All the watermarked scenes, not frames, need to be dropped for an effective attack against the watermark. Dropping of scenes makes the video less attractive for illegal copying and distribution.

2PASCD: An Efficient 2-Pass Abrupt Scene Change Detection Algorithm

Scene change detection in videos is a primary requirement of video processing applications used for the purpose of generating data needed by video data management systems and digital rights management (DRM) systems. Scene change data can be used in DRM systems for effective IPR protection by means of watermarking and fingerprinting selected scenes. In this paper, we present a 2-pass algorithm for abrupt scene change detection in videos based on x2 color histogram comparison of subwindows of successive frames and sliding window detector method. In the proposed method, we improve the efficiency of scene change detection by a second level inspection of the detected scene changes using a fixed average and a moving average to ascertain whether the detected scene boundary is correct or the scenes need to be combined. This method gives precision and recall values better than any existing method.

Multi-user Attribute Based Searchable Encryption

Globalized services economy is increasingly adopting cloud computing in which applications, platforms, and infrastructure are available as services. Huge volume of data including sensitive data is outsourced and stored remotely in public clouds. There is a need for efficient protection of the privacy and security of users and their data without affecting its utility to authorized users. There needs to be a trade-off between data security and availability. Multi user encryption schemes provide partial solution by encrypting data and managing keys efficiently among the users but exposing the entire data accessible to all the users. But, in certain applications, the data need to be accessed by only specified users and they shall have access to only specified parts of the data on a need to know basis. Ciphertext policy attribute based encryption supports keyword based search but require large amount of data for a single keyword thereby increasing the size and hence the cost of storage on the cloud. In this paper, we have proposed an encryption scheme which requires less storage space on the cloud but provides fine grained access control to authorized users. This is a hybrid scheme that combines the strengths of both attribute based encryption and searchable encryption.

NoMark: A Novel Method for Copyright Protection of Digital Videos without Embedding Data

Copyright protection of digital media content is becoming increasingly important with increasing potential for content monetization which is attributable to digital convergence. High volumes of uploaded content in social networking and media sharing sites makes it increasingly difficult to monitor all the uploaded content for copyright infringement, piracy and illegal distribution. Currently, digital watermarking is predominantly used for copyright protection of images and videos. Watermarking involves embedding data into an image or a video in an invisible or visible manner. This traditional method is prone to many known watermark attacks aimed at detecting and distorting or destroying the embedded data. In this paper, we present the No Mark Method, a robust, reliable, and efficient scheme for copyright protection of digital video content without embedding any data in to it. The method is based on visual cryptography and can be used to watermark individual scenes in a video and hence protects not only the copyright of complete video but also of each individual scene in the video. The method is robust against video fragmentation attack, unauthorized insertion of scenes from a protected video into another video and various other video watermarking attacks. There is no involvement of any notary agency to establish copyright ownership of a digital video.

Anonymous Searchable Encryption Scheme for Multi-user Databases

With the ever advancing technology of fast information processing, protecting data with only access control mechanisms is becoming increasingly difficult. If someone breaks into a database, the entire data will be compromised if it is in plaintext form. One quick remedy is to keep the data in encrypted form. However, encryption will make it difficult to do any operations on the data. This has prompted considerable research in the last decade and has led to various schemes of searchable encryption. It allows search over the encrypted data. There are various techniques which support different levels of querying, making it suitable for variety of applications. However, almost all of them are either symmetric-key or single-user schemes or require key sharing. Here, we are proposing a new scheme which will allow multiple users to encrypt, store and decrypt their own data, along with support for doing data searches over all the data by other users.

Data Protection and Privacy Preservation Using Searchable Encryption on Outsourced Databases

With the increasing popularity of social networks in the globalized environment, the process of sharing data and information from anywhere at anytime has become easier and faster. Furthermore, cloud based computing and storage services have become mainstream. Unfortunately, if the information is on the Internet, it is susceptible to attacks leading to leakage and hence needs to be encrypted. Searchable encryption is a way to obtain efficient access to a large encrypted database, improving the data security even when it is stored on untrusted servers. We present few applications which can use and benefit from searchable encryption and explain how secrecy of the data is maintained without compromising usability.

A system to provide primary healthcare services to rural India more efficiently and transparently

Wireless technologies are evolving in rapid pace and becoming cheaper - this can be used to facilitate providing primary healthcare services in rural India. We have built a decision support system which can provide first level assessment of a patient by taking all the symptoms as well as vital parameters like heart rate, blood pressure, etc. It can also provide some basic treatment suggestions like Oral Rehydration Salts (ORS) for diarrhea, etc. The patient details as well as assessment can be uploaded to a server, which can be assessed by a doctor to provide actual treatment. The patient details can also be used for analytical purpose for drafting plans for future by Government agencies. The system also works as personal assistant for ASHA (Accredited Social Health Activist) health workers to assist them to do their job efficiently. This system mainly has three components: Mobile Client, Server and Database. Mobile clients are used to collect data from patients and provide first level assessment. Server component will process the data for the purpose of analysis and Authorized Doctors can retrieve patient details, ask few more questions to the patient via ASHA worker and can provide treatments over SMS or email. Database system will be used to archive data for analysis purposes.

Disease management: clustering–based disease prediction

The latest trends in healthcare industry have made enormous data available which is useful for disease prediction. This may be utilised by provider/payer for disease management study (DMS) for judging the present health condition and analysing disease trends. The present approach depends upon objective analysis which is based on binary value of symptoms and health indicators and direct relation between them. We propose a framework based on analytics to diagnose and predict diseases using enhanced genetic clustering using patient history, symptoms, and existing medical condition. New patients profile is analysed against existing patterns and mapped to a particular cluster based on the patients medical parameters. After cluster formation, cohesion and adhesion between the clusters is determined, which helps to predict present medical condition and probability for being prone to a disease in future. This framework provides an efficient disease management based on the preliminary diagnosis of the patient.

On-the-fly Watermarking of Videos for Real-time Applications

In order to prevent piracy of digital media content, Digital Watermarking has emerged as a potential alternative to existing methods such as Digital Rights Management (DRM) based systems. For real-time watermarking applications, digital watermarking method should consume less time for embedding the watermark while remaining robust against attacks. This paper presents on-the-fly video watermarking method for the copyright protection of videos and also addresses implementation issues in real-time applications. Experimental results show that the proposed method requires less computational time for embedding the watermark and hence is suitable for real-time applications. The results also show that the method is robust against attacks. The proposed method is compared with other watermarking algorithms and it yields better results in terms of complexity and robustness.

Transcoding resistant robust watermarking technique using entropy-based selective spread spectrum

The growth of the internet makes it easier for data owners to transfer digital multimedia content over the internet. This provides an environment where hackers can easily scoop the content and illegally redistribute it which increases the need for efficient copyright protection mechanisms like digital watermarking. The future internet will have various heterogeneous devices like laptop, mobile and IPTV which require the data to be transcoded according to the end user devices. But the process of transcoding affects the embedded watermark making it difficult to prove the ownership rights. The current scenario is to embed the watermark in the content after it has been transcoded which requires watermarking the same content after each transcoding. This paper investigates the effects of transcoding on watermark and recommends a robust watermarking algorithm such that watermark can be embedded in the original content once and can be retrieved even after the content is transcoded.