We have investigated many issues involved in the design and implementation of an image spreadsheet. Although we have not fully implemented all of our ideas in the LIS, we do have a version which provides several of the crucial operations necessary. We have a spreadsheet grid; we can evaluate formulae; we can load and display an image within a cell's boundaries. We have already done most of the footwork involved in designing and implementing a much more extensive version.

The aspect of our design which is most useful is that is it very easily extendible. The design is overall loosely coupled which provides easy replacement of parts. Several functional capabilities such as cell referencing and priorities for dependency chain calculation are partially implemented and could be fully implemented within a short time.The framework to implement most of the range of issues we have investigated exists in the design.

This project has been a very ambitious one and in that light it has been appropriate to build an application which is in effect a vehicle for a much larger program.

We have recognised several weaknesses in the organisation of the project which if avoided might have resulted in more of the LIS being implemented. We discovered at a late stage in implementation that there should have been more communication between team members. What tended to happen was that people were working in isolation on their individual problem which in several instances led to a misunderstandings of exact implementation detail and to difficulties in integrating modules.

Another communication problem was that the designer of the model had worked on the design alone and the rest of the team did not have as full a knowledge of the overall design.

Possible Extensions

There are several extensions that we view as being the next step in the implementation of the LIS. Cell referencing and dependency chain calculation can be fully implemented. We would like to extend the user interface to provide more spreadsheet functionality such as multiple selections and standard spreadsheet operations for editing, filling down/across etc. A set of on screen formatting options such as changing font style, drawing boxes around text and hiding the spreadsheet grid. Widgets would be very useful. The extension of the LIS to handle movie files, to play and to edit them.

There has been some commercial interest shown in our project and it is hoped that the development of the LIS will be continued over this summer. We hope that the paradigm of the Large Image Spreadsheet will be further explored and that our work will be continued.