The VIMODULE represents the WEDELMUSIC SYSTEM's extensions for visually impaired persons. However, the module contains tools that need to be accessible from sighted persons as well, such as the SPOKEN MUSIC MODULE and the BRAILLE PRINTING MODULE. Aside from these tools, the main role of the VIMODULE is to render the WEDELMUSIC EDITOR's functionality accessible to VIs.
To this end, it makes implicit or explicit use of the following services:
- Screen-Reader: The VIMODULE does not actually communicate directly with this component, but it certainly relies on its presence to handle focus changes, menu navigation, etc. providing appropriate audible feedback. After all, the WEDELMUSIC VIEDITOR is a typical Windows application itself and can be treated by the screen-reader the same standard way.
- Speech Synthesiser: In order to provide additional information to the user, when appropriate, a Text to Speech (TtS) converter is required that supports the three project languages. This TtS converter will be explicitly controlled by the system.
These are basically the modalities external to the overall system that the WEDELMUSIC VIMODULE interacts with (implicitly or explicitly).
The WEDELMUSIC VIMODULE itself is divided into the following independent modules and components:
- The WEDELMUSIC VIEDITOR. It is a simplified version of the WEDELMUSIC EDITOR targeted to the visually impaired persons. It contains a set of commands for:
- Retrieving information related to the WEDELFORMAT header of the active file, as well as classification, identification, structural, and other information.
- Browsing through a score using a caret-like mechanism. Information is automatically provided relatively to both the current caret location and the symbols in the vicinity of it.
- Editing by means of inserting, deleting, modifying, marking, copying and pasting isolated symbols or entire measures.
- Reproduction of any portion of the score. This involves diverse actions such as playback, producing a hardcopy using a Braille printer, or transforming the part of the score to the SPOKEN MUSIC component.
- Multilingual TtS. Spoken messages are involved in all the previously described actions, both to assist the VI users to select the respective commands and to provide feedback on the results of their actions on the currently active score. It is more than usual that mixed-language messages may need to be conveyed to the user by the WEDELMUSIC VIEDITOR, e.g. when combining information in the user's language with information in the system's language or in the default language used by a third party application. Those cases are handled by the next two components, namely the LANGUAGE IDENTIFICATION COMPONENT and the TTS SCHEDULING AND ROUTING COMPONENT described in the following.
- The LANGUAGE IDENTIFICATION COMPONENT. The role of this component is to break the target text or sentence down to monolingual parts. Each part can be sent to a different TtS engine.
- The TTS SCHEDULING AND ROUTING COMPONENT. The role of this component is to serve requests for TtS conversion for a set of monolingual texts. Each text is routed to the appropriate TtS engine to convert it, while the next text is waiting in an internal queue for it to finish so that it can proceed to its conversion. An additional task of this component is to schedule the overall process and marshal the access to the audio hardware.
- The BRAILLE PRINTING MODULE. This module handles all the details for printing a portion of a score to a Braille printer, e.g. selecting the target printer, setting the printing options, and performing the actual data transmission.
- The SPOKEN MUSIC MODULE. This module handles all the details for music-to-speech conversion in the user selected language.