Sharif Digital Repository

In this paper, a frame-based method with reference frame was proposed to recognize six basic facial emotions (anger, disgust, fear, happy, sadness and surprise) and also neutral face. By using face landmarks, a fast algorithm was used to calculate an appropriate descriptor for each frame. Furthermore, Linear Discriminant Analysis (LDA) was used to reduce the dimension of defined descriptors and to classify them. The LDA problem was solved using the least squares solution and Ledoit-Wolf lemma. The proposed method was also compared with some studies on CK+ dataset which has the best accuracy among them. To generalize the proposed method over CK+ dataset, a landmark detector was needed.... 

The quality assessment is a vital routine in videorelated industries such as broadcast service providers. Due to the duration and the excessive number of the video files, case by case assessment of the files by operators is no longer feasible. Therefore, a computer-based video quality assessment mechanism is the only solution. While it is common to measure the quality of a video file at the compression stage by comparing it against the raw data, at later stages no reference video is available for comparison. Therefore, a no-reference (Blind) video quality assessment (NR-VQA) technique is essential. The common NRVQA methods learn a quality metric based on a number of features extracted from... 

With the ever-growing portion of internet traffic associated with multimedia data and the existence of multiple copies of the same content in various forms, it has become vital to measure the quality of the image and video files. In most cases, without access to the original file, the quality shall be assessed solely based on the available file. Specifically, the challenge of no-reference image quality assessment (NR-IQA) is to predict a quality measure for given images in a consistent manner with human perception of quality. Conventional NR-IQA methods try to fit certain distortion models to a given image and quantify the quality. In practice, however, an image is affected by a combination... 

With the recent advancements in deep learning, high performance neural networks have been introduced. These neural networks also can be used to solve similar problems in a transfer learning approach. Recently, several state-of-The-Art Convolutional Neural Networks (CNNs) are proposed for computer vision tasks. On the other hand, in-The-wild No-Reference (Blind) Image Quality Assessment (NR-IQA) problem is known as a challenging human perceptual problem. In this paper, a transfer learning approach is used to solve the problem of in-The-wild NR-IQA. With a few training times, the proposed neural network exceeds all the previous methods which are not using deep neural networks. Further, the... 

Video quality assessment is a crucial routine in the broadcasting industry. Due to the duration and the excessive number of video files, a computer-based video quality assessment mechanism is the only solution. While it is common to measure the quality of a video file at the compression stage by comparing it against the raw data, at later stages, no reference video is available for comparison. Therefore, a noreference (Blind) video quality assessment (NR-VQA) technique is essential. The current NR-VQA methods predict only the mean opinion score (MOS) and do not provide further information about the distribution of people score. However, this distribution is informative for the evaluation of... 

With the emergence of social networks and improvements in the internet speed, the video data has become an ever-increasing portion of the global internet traffic. Besides the content, the quality of a video sequence is an important issue at the user end which is often affected by various factors such as compression. Therefore, monitoring the quality is crucial for the video content and service providers. A simple monitoring approach is to compare the raw video content (uncompressed) with the received data at the receiver. In most practical scenarios, however, the reference video sequence is not available. Consequently, it is desirable to have a general reference-less method for assessing the... 

In this letter, we consider the problem of blind source separation under certain nonlinear mixing conditions using a deep learning approach. Conventionally, the separation of sources within linear mixtures is achieved by applying the independence property of the sources. In the nonlinear regime, however, this property is no longer sufficient. In this letter, we consider nonlinear mixing operators where the non-linearity could be fairly approximated using a Taylor series. Next, for solving the nonlinear BSS problem, we design an end-to-end recurrent neural network (RNN) that learns the inverse of the system, and ultimately separates the sources. For training the RNN, we employ a set of... 

Prostate Cancer has become one of the deadliest cancers among males in many nations. Pathologists use various approaches for the detection and the staging of prostate cancer. Microscopic inspection of biopsy tissues is the most accurate approach among them. The Gleason grading system is used to evaluate the stage of Prostate Cancer using prostate biopsy samples. The task of assigning a grade to each region in a tissue is a time-consuming task. Furthermore, this task often has several challenges since it has considerable inter-observer variability even among expert pathologists. In this paper, we propose an automatic method for this task using a deep learningbased approach. For this purpose,... 

Reusing the programs which have already been developed can shorten the production time and reduce costs and expenses. One of the important issues in software reuse is finding a program or a program component in a program library which has been already developed and using it in the new program. In view of precision and automation that formal methods can provide, we can use formal methods in retrieval appropriate components from the software libraries. In this paper, some of the works done in the field of retrieval of the components from the libraries by the help of formal methods have been surveyed and reviewed  

The mobile phone is one of the technologies which are widely used these days. It is available in most countries and all people, even children and elderly people can use it. It seems that in the near future, each person will have at least one mobile phone. So it is a good choice for communication in emergency situations, such as a heart attack or after an earthquake. In this chapter, we will survey a number of systems which are designed for communication in emergency situations and then explain three systems which are developed by the authors. The first one is for locating and rescuing victims after an earthquake. The second system is for calling an emergency team by patients in emergency... 

There are many websites specially designed for mobile phones. Some hackers write automated programs to abuse these website services and waste the website resources. Therefore, it is necessary to distinguish between human users and computer programs. Methods known for achieving this are known as CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart). CAPTCHA methods are mainly based on the weaknesses of OCR (Optical Character Recognition) systems and ask the user to type a word. So using them is difficult in tools such as PDAs (Personal Digital Assistant) or mobile phones that lack a complete keyboard. In this paper, a new CAPTCHA system is proposed for... 

Nowadays, a great amount of information is circulated through the Internet. Some of them exclusively belong to a special group of users and require protection and safeguarding against unauthorized access. To this end, a category of systems called HIP (Human Interactive Proof) are designed to distinguish between various groups of users. An important task on the Internet websites is registration. Some hackers write programs to make fake registration that waste the resources of the web sites or even stop them from providing services. Therefore, human users should be distinguished from computer programs. CAPTCHA (Completely Automatic Public Turing Test to Tell Computer and Human Apart) methods... 

Feedback vibration is a standard feature in almost every home video game console controller to vibrate in selected circumstances, such as when the user's character kick the ball or hit the opponent, to immerse the player in the game. In the handheld game consoles this feature causes the handheld game consoles to vibrate. But the handheld game consoles are different than home video game consoles. In this paper we examine the suitability of using feedback vibration in the handheld game consoles. We evaluated feedback vibration popularity among the users. We used Nintendo DS handheld game consoles for this evaluation  

In some websites it is necessary to distinguishing between human users and computer programs which is known as CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart). CAPTCHA methods are mainly based on the weak points of OCR systems and using them are undesirable to human users. In this paper a method has been presented for distinguishing between human users and computer programs on the basis of choice of an object shown on the screen. In this method some objects are chosen randomly and the pictures of these topics are downloaded from the Internet. Then after applying some effects such as rotation, all of the pictures are shown on the screen. Then we ask the... 

This paper presents a new approach for hiding information in speech signals. In this method, the silence intervals of speech are found and the length (number of samples) of these intervals is changed to hide information. This method can be used simultaneously with other methods. © 2008 IEEE  

Nowadays the Internet users are from different ages and groups. Disabled people are a group of the Internet users. Some websites are especially created for disabled people and public access to them is undesirable. In this paper, for the first time, a method is introduced for distinguishing between deaf persons and other users using a new HIP (Human Interactive Proofs) system. In this method, the sign language is used. A word is shown as a movie using a sign language. The user should recognize the word and select it from a list. Only deaf persons can understand sign language and recognize the word, therefore other persons and also computer programs cannot enter the website. This project has... 

Nowadays the Internet users are from different ages and groups. The disabled people also use the Internet. Some websites are especially created for disabled people. Many Internet sites offers services for human users, but unfortunately some computer programs are designed which abuse these services. As a result some systems named CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart) have been introduced to tell apart human users and computer software. In this paper, a new CAPTCHA method is introduced which can be used by blindpeople. In this method a simple mathematicalproblem is created according to predefined patterns and converted to speech using a... 

Nowadays, many daily human activities such as education, commerce, talks, etc. are carried out through the Internet. In cases such as the registering in websites, some hackers write programs to make automatic false enrolments which waste the resources of the website while this may even stop the entire website from working. Therefore, it is necessary to tell apart human users from computer programs which is known as CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart). CAPTCHA methods are mainly based on the weak points of OCR (Optical Character Recognition) systems while using them are undesirable to human users. In this paper a method has been presented for... 

Sending information secretly and communicating covertly have been of great interest for ages. On the other hand, text documents have been widely used and consequently various methods for hiding information in texts (Text Steganography) have been developed so far. In this paper a new method is proposed to hide information in digital Persian and Arabic Unicode texts. In Persian and Arabic, each letter can have four different shapes regarding to its position in the word. In this method by using this feature of Persian and Arabic languages and the way which documents are saved in the Unicode Standard, the information is hidden in Unicode text documents. This method has a good hiding capacity...