FCN Iris Recognition on FPGA via Quantization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing iris recognition systems face challenges in achieving efficient and accurate processing due to computationally intensive fully convolutional network (FCN) architectures, which are not optimized for resource-constrained embedded systems, leading to high computational complexity and limited deployment on mobile and wearable devices.

Innovation Solution

A three-step software/hardware co-design methodology is employed, including FCN architectural exploration, precision quantization using 8-bit dynamic fixed-point format, and hardware acceleration, to develop a resource-efficient iris recognition pipeline with FCN-based segmentation, contour fitting, and Daugman normalization and encoding, implemented on an embedded FPGA platform.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If FCN-based segmentation is used for accurate iris recognition, then segmentation accuracy is improved, but computational complexity increases

Engineering Contradiction:
Improvesegmentation accuracyVSAvoidcomputational complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies precision quantization by changing the data representation parameter from high-precision floating-point to 8-bit dynamic fixed-point format. This parameter change reduces the computational complexity and resource requirements while maintaining segmentation accuracy, directly resolving the contradiction between accuracy and complexity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent substitutes the software-based FCN implementation with a dedicated hardware accelerator circuit. This replacement transforms the computational mechanism from software processing to hardware processing, significantly reducing computational complexity and enabling deployment on resource-constrained embedded systems while preserving segmentation accuracy.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If FCN-based segmentation is used for accurate iris recognition, then segmentation accuracy is improved, but processing time increases

Engineering Contradiction:
Improvesegmentation accuracyVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent replaces the software-based FCN processing with a hardware accelerator, fundamentally changing the processing mechanism from sequential software execution to parallel hardware computation. This substitution dramatically reduces processing time while maintaining segmentation accuracy, resolving the contradiction between accuracy and processing speed.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent performs precision quantization to 8-bit dynamic fixed-point format before hardware implementation. This preliminary action prepares the data in a format optimized for hardware processing, enabling faster computation while preserving the accuracy needed for segmentation, thus reducing processing time without sacrificing accuracy.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If full-precision floating-point FCN is implemented, then segmentation accuracy is improved, but resource utilization increases

Engineering Contradiction:
Improvesegmentation accuracyVSAvoidresource utilization
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent changes the precision parameter from full-precision floating-point to 8-bit dynamic fixed-point format. This parameter change reduces the quantity of computational resources (registers, memory, arithmetic units) required while maintaining segmentation accuracy, directly resolving the contradiction between accuracy and resource utilization.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses lower-precision 8-bit fixed-point arithmetic instead of high-precision floating-point arithmetic. This substitution uses a simpler, less resource-intensive computational representation that consumes fewer hardware resources while maintaining sufficient accuracy for iris segmentation, resolving the resource utilization contradiction.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS11113553B2Iris recognition using fully convolutional networks
Publication Date: 2021.09.07 BROWN UNIVERSITY
  • US11113553B2 patent drawing
  • US11113553B2 patent drawing
  • US11113553B2 patent drawing

AI summary

A method of accelerated iris recognition includes acquiring an image comprising at least an iris and a pupil, segmenting the iris and the pupil using a fully convolutional network (FCN) model, normalizing the segmented iris, encoding the normalized iris, the normalizing and encoding using a rubber sheet model and 1-D log Gabor filter, and masking the encoded iris.