Programmable Mediaprocessor Research Articles

Efficient 2D FFT implementation on mediaprocessors

We have developed an efficient implementation to compute the 2D fast Fourier transform (FFT) on a new very long instruction word programmable mediaprocessor. Using instruction-level parallelism and a multimedia instruction set, our radix-4 Cooley–Tukey algorithm optimally maps the FFT computation to the processing resources of the Hitachi/Equator’s MAP mediaprocessor. We have also achieved more efficient data I/O and lower data transfer time compared to traditional implementations by processing several columns in parallel during the column-wise stage of row–column decomposition. We used a programmable direct memory access engine and a double-buffering scheme in the data cache to perform the computation and the data transfer in parallel. Our implementation resulted in 22.4 ms total execution time for a 512 × 512-point 2D complex FFT, which is faster than previous single-chip programmable or dedicated solutions. The implementations on two other mediaprocessors, the TriMedia TM1100 and the BOPS ManArray, illustrate the importance of the instruction set architecture for achieving high performance and the trend of data I/O becoming the limitation on the 2D FFT performance in newer mediaprocessors.

The MAP1000A VLIM mediaprocessor

Presents the MAP1000A, an alternative to using custom ASICs for each multimedia-processing task. It is a single-chip, programmable mediaprocessor that also makes use of general-purpose RISC processing and a view framework. It provides a new programmable infrastructure with the cost, performance, and power characteristics suitable for replacing RISCs and ASICs in consumer electronics, communications, and imaging applications while, retaining a completely high-level-language programming approach. This single-chip mediaprocessor handles all digital functions in high-level-language software with significantly improved performance and without increased system cost or development complexity.

Interactive three-dimensional ultrasound using a programmable multimedia processor

We developed an interactive three-dimensional (3D) ultrasound (US) workstation that is inexpensive and suitable for use in research and clinical environments. Our personal computer–based system produces 3D volumes by acquiring a series of 2D images from a commercial ultrasound scanner, spatially registering the images using an electromagnetic position sensor, and reconstructing the data into a regular 3D Cartesian volume. The 3D US system uses an imaging board based on the Texas Instruments TMS320C80 Multimedia Video Processor (MVP), a fully programmable mediaprocessor that includes multiple processing units on a single chip. We developed efficient volume reconstruction and visualization algorithms for the MVP that allow our 3D US system to provide the same immediate feedback as current 2D US technologies with the added advantage of presenting information in three dimensions. For example, for acquired sequences of 512 × 512 US images, volumes can be reconstructed using six degree-of-freedom position measurements at 11.4 frames/s. A modified reconstruction algorithm that performs incremental reconstruction was developed to enable real-time volume reconstruction and visualization during acquisition and operates at 12.5 frames/s. US volumes can be rendered via shear-warp factorization and maximum intensity projection (MIP) at 10 frames/s for 128 × 128 × 128 volumes and 1.45 frames/s for 255 × 255 × 255 volumes. © 1998 John Wiley & Sons, Inc. Int J Imaging Syst Technol 9: 442–454, 1998