Intel® Hyperflex™ Architecture High-Performance Design Handbook

ID 683353
Date 10/04/2021

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Document Table of Contents

4.1. Median Filter Design Example

The Median filter is a non-linear filter that removes impulsive noise from an image. These filters require the highest performance. The design requirement is to perform real time image processing on a factory floor.

You can find the supporting design example project and design files for this walk-through at You can download and unzip the verified project, constraint, design, RTL from the to complete this walkthrough.

Figure 97. Before and After Images Processed with Median Filtering

Median Filter Design Example Files

After download and extraction, the Median filter design example .zip file contains the following directories under the Median_filter_design_example_<version> directory:

Table 9.  Median Filter Design Example Files
File Name Description
Base Contains the original version of the design and project files.
Final Contains the final version of the design and project files with all RTL optimizations in place.
fpga-median.ORIGINAL Contains the original OpenSource version of the Median filter and the associated research paper.
Step_1 Incremental RTL design changes and project files for Fast Forward optimization step 1.
Step_2 Incremental RTL design changes and project files for Fast Forward optimization step 2.

This walk-through covers the following steps:

The paper An FPGA-Based Implementation for Median Filtering Meeting the Real-Time Requirements of Automated Visual Inspection Systems first presented this design at the 10th Mediterranean Conference on Control and Automation, Lisbon, Portugal, 2002. The design is publicly available under GNU General Public License that the Free Software Foundation publishes.