A key element of any software development is the architectural design. In the same way the architecture of a building not only defines the look of the finished construction but also the materials, structures and how they all fit together, these things must all be defined for a software framework. This is especially important for projects such as ImAc where different partners are responsible for the development of each component and major changes can be very costly later in terms of development time.
In order to minimize risk the ImAc architecture is being developed in two iterations, each followed by a pilot study to evaluate success and provide an iterative development cycle. Our technical architecture is directly based of the user requirements, which provide an essential checklist of system requirements that we will need to satisfy in order to achieve success. It will also form the basis for our integration and testing strategy. We have adopted the ‘4+1’ methodology  for software architecture, which wraps each technical view around a scenario designed to illustrate significant and central functionalities.
Figure 1 – the ImAc adoption of the 4+1 Methodology
These scenarios are described using a use-case view in order to highlight significant and central functionality. They also describe the set of cases that have a substantial architectural coverage (that exercise many architectural elements) or that stress or illustrate a specific, delicate point of the architecture. Table 1 shows an overview of the scenarios considered within the ImAc project.
Table 1 – Overview of Scenarios
|Production Editors||S1||Production of New Subtitles|
|S2||Subtitle Verification and correction|
|S3||Production of Audio Description|
|S4||Audio Description Verification and Correction|
|S5||Production of Sign Language|
|S6||Sign Language Verification and Correction|
|S7||Object Based Audio Editing|
|Accessibility Content Manager||S8||Assignment of videos for the accessibility content production|
|S9||Getting an Accessibility Content file|
|S10||Generating Different audio formats with an audio renderer|
|Content Packaging and Distribution||S11||Preparation of Contents|
|Player||S13||Consumption of media Contents|
The ImAc technical partners are currently preparing to publish the first iteration of the system architecture, providing a blueprint for the technical implementation of the project. This will provide the skeleton for the first project pilots and will be updated after the initial testing phase to reflect changes needed to improve the platform.
 Kruchten, Philippe (1995, November). Architectural Blueprints — The “4+1” View Model of Software Architecture. IEEE Software 12 (6), pp. 42-50.
By Chris Hughes