In this paper, we present improved alternative sequential filter-edge detector using generalized directional morphological filters. Based on the properties of effective noise removal and detail preservation of the generalized directional morphological filters, we apply these filters to edge detection of noisy images. The performance of the edge detection in the presence of mixed noise is evaluated. Simulations show that edge detection method using generalized directional morphological filters can also improve the performance.

In this paper, we present the design and implementation of a cost effective Ethernet over HDLC forwarding VLSI for network access system. It supports 10/100 Mbps Ethernet PHYs and up to 50 Mbps HDLC interface directly applied to Modem or transceiver. The maximum forwarding/filtering rate is 90,000 pps with a throughput latency of 1 frame, which supports high speed applications. It can also support both master mode for Ethernet PHY and slave mode for switching chip by the pin configuration. It has been implemented as a single chip based on 0.5 µm CMOS technology. Field test shows that the wire-speed packet forwarding and processing using by the implemented chip can be achieved.