As it can be guessed from the name, the pict gray-scale image widget is based on the photo image widget. After few experiments, it became clear that the photo widget was not appropriate for our application. First, this widget can only handle 8- or 24-bit color images, and it does not provide any mechanism to visualize floating-point images. Next, the colors are allocated statically and cannot be changed dynamically by the user. Thus, we decided to implement a new widget by focusing on data management and color allocation.