Recently, smartphones are widely used and they are developing fast. User interfaces of smartphone have been developed from keypad-based interface to Graphic User Interface (GUI). It is the most frequently used interface, which has a lot of advantages; it is easy to use and attractive for non-technical users because it is intuitive. Especially, it is very useful in smartphones because most of them does not have keyboard . However, this interface is not convenient for people who have problems touching the screen or who have impaired vision. As an alternative, Speech User Interfaces (SUI) is gaining popularity. SUI uses speech as input and output. Many technologies based on this interface have been developed. For speech output, Text-To-Speech (TTS) is used to create artificial, human-like voice. Therefore, TTS can help visually impaired people or the person who has problem in using hands. Furthermore, TTS can be used in emergency situations. For instance, people in urgent situations need clear, calm, consistent communication when e.g. an accident happens. TTS can give clear and calm speech to users.
The goal of my thesis is to make an application that reads the content of the clipboard using Text-to-Speech. There are several features of the applications. First, it has multilingual support (currently Hungarian and English). The users are able to change the language in preference menu. Second, it supports shaking gesture, which means that the application read the last text copied to clipboard when the device is shaken. Third, the application operates as a background service, which makes it possible to read with long texts aloud. Fourth, it provides the function of saving texts which was copied to clipboard earlier. Fifth, the application provide preference menu to give the users chance to configure the user interface which are fitted to them. The items of preferences are the settings for repetition of utterance, the setting for font size, the setting for changing languages, the settings for shaking gesture, and the setting for changing color of use interface. Sixth, the application is able to detect the text and notify users what language is used for the given text.
In Chapter 1 there is basic information about Android. In addition, the principle of operation of TTS and the area where it is useful are introduced. In Chapter 2 unit selection and statistical parametric speech synthesis are explained. They are fundamental technologies to synthesize speech and essential part of TTS. In Chapter 3 the characteristics of the application using TTS are shown. In Chapter 4 the application is analyzed in code level. The role of classes and theirs relation are scrutinized. In Chapter 5 the evaluation of the application by a group of people is presented. In last chapter the comprehensive conclusion of thesis is commented.