This paper presents the Array-OL specification language. It is a high-level visual language dedicated to multidimensional intensive signal processing applications. It allows to specify both the task parallelism and the data parallelism of these applications on focusing on their complex multidimensional data access patterns. This presentation includes several extensions and tools developed around Array-OL during the last few years and discusses the mapping of an Array-OL specification onto a distributed heterogeneous hardware architecture.