Semantic Image Segmentation with Task-Specific Edge Detection Using CNNs and a Discriminatively Trained Domain Transform

TL;DR

Semantic segmentation using CNN and Domain Transform, achieving 66.35% mIOU with improved boundary precision.

cs.CV 🔴 Advanced 2015-11-11 41 views
Liang-Chieh Chen Jonathan T. Barron George Papandreou Kevin Murphy Alan L. Yuille
semantic segmentation edge detection CNN domain transform computational efficiency

Key Findings

Methodology

This paper introduces a semantic image segmentation method combining deep convolutional neural networks (CNNs) and domain transform (DT). By learning task-specific edge maps from intermediate CNN layers and applying domain transform for edge-preserving filtering, the segmentation accuracy is significantly improved.

Key Results

  • On the PASCAL VOC 2012 dataset, the model using domain transform improved by 4.1% over the baseline, reaching 66.35% mIOU.
  • Compared to Dense CRF, domain transform is 4.6 times faster, with only 1.2% lower performance.
  • Combining Dense CRF further improves performance to 68.44% mIOU.

Significance

This research significantly improves boundary precision in semantic segmentation while greatly reducing computational costs. By employing task-specific edge detection, it addresses the issue of inaccurate boundary localization in traditional methods, impacting both academia and industry.

Technical Contribution

Introduced a new edge detection method combining CNN intermediate features and domain transform, offering new engineering possibilities and outperforming existing methods in computational efficiency.

Novelty

First to apply domain transform to semantic segmentation, achieving end-to-end training by learning task-specific edge maps, differing from traditional image gradient methods.

Limitations

  • Edge detection may be inaccurate in complex backgrounds, affecting segmentation results.
  • Performance of domain transform depends on the quality of the edge map.

Future Work

Future work could explore more complex edge detection models and combine other filtering methods to further enhance segmentation accuracy and efficiency.

AI Executive Summary

Semantic image segmentation is a crucial task in computer vision, with traditional methods falling short in boundary localization. This paper proposes an innovative method combining deep convolutional neural networks (CNNs) and domain transform (DT). By learning task-specific edge maps from intermediate CNN layers and applying domain transform for edge-preserving filtering, segmentation accuracy is significantly improved.

On the PASCAL VOC 2012 dataset, the model using domain transform improved by 4.1% over the baseline, reaching 66.35% mIOU. Although slightly lower in performance compared to Dense CRF, it is 4.6 times faster. Combining Dense CRF further improves performance to 68.44% mIOU.

This method not only has significant academic impact but also offers new possibilities for industrial applications. Future work could explore more complex edge detection models and combine other filtering methods to further enhance segmentation accuracy and efficiency.

Deep Analysis

Background

Semantic image segmentation is a crucial task in computer vision, aiming to assign semantic labels to each pixel in an image. In recent years, deep convolutional neural networks (CNNs) have made significant progress in this field, but traditional methods fall short in boundary localization.

Core Problem

Traditional semantic segmentation methods struggle with accurate boundary localization, especially in complex backgrounds. This is due to the pooling layers in CNNs that lead to loss of spatial information, affecting segmentation accuracy.

Innovation

This paper proposes an innovative method combining CNN and domain transform. By learning task-specific edge maps from intermediate CNN layers and applying domain transform for edge-preserving filtering, segmentation accuracy is significantly improved.

Methodology

  • �� Use DeepLab model for initial semantic segmentation prediction.
  • �� Utilize EdgeNet to extract features from intermediate CNN layers for edge prediction.
  • �� Apply domain transform to filter segmentation results, improving boundary precision.

Experiments

Experiments were conducted on the PASCAL VOC 2012 dataset, comparing different edge detection methods. mIOU was used as the primary evaluation metric, with hyperparameter tuning performed.

Results

The model using domain transform improved by 4.1% over the baseline, reaching 66.35% mIOU. Combining Dense CRF further improves performance to 68.44% mIOU.

Applications

This method can be applied in fields like autonomous driving and medical image analysis, significantly improving boundary localization precision and reducing computational costs.

Limitations & Outlook

Edge detection may be inaccurate in complex backgrounds, affecting segmentation results. Performance of domain transform depends on the quality of the edge map.

Plain Language Accessible to non-experts

Imagine a factory where workers need to sort different products. Traditional methods are like workers using their eyes to judge the product category, prone to errors. This method is like equipping workers with high-tech scanners that can quickly and accurately identify product edges and categories. This way, the factory's efficiency and accuracy are significantly improved.

ELI14 Explained like you're 14

Hey, buddies! Imagine you're playing a game where you need to sort characters on the screen into different teams. Traditional methods are like using your eyes to judge the team's characters, easy to mess up. This new method is like giving you super glasses that can quickly and accurately identify character edges and teams. This way, you can easily win the game!

Glossary

Domain Transform

An edge-preserving filtering method controlled by a reference edge map.

Used to replace traditional fully-connected CRF, improving computational efficiency.

Convolutional Neural Network (CNN)

A neural network structure used for image processing, excels at extracting image features.

Used for initial semantic segmentation prediction.

Edge Detection

A technique for identifying object boundaries in images.

Generated by EdgeNet using intermediate CNN layer features.

Dense CRF

A post-processing method for improving segmentation accuracy using fully-connected conditional random fields.

Combined with domain transform to enhance segmentation accuracy.

mIOU

Mean Intersection-over-Union, used to measure segmentation model performance.

Used as the primary evaluation metric in experiments.

Open Questions Unanswered questions from this research

  • 1 How to improve edge detection accuracy in complex backgrounds remains to be further studied.
  • 2 The combination effects of domain transform with other filtering methods have not been fully explored.

Applications

Immediate Applications

Autonomous Driving

Enhances vehicle ability to recognize road boundaries and obstacles, improving safety.

Long-term Vision

Medical Image Analysis

Improves disease diagnosis accuracy through precise boundary identification.

Abstract

Deep convolutional neural networks (CNNs) are the backbone of state-of-art semantic image segmentation systems. Recent work has shown that complementing CNNs with fully-connected conditional random fields (CRFs) can significantly enhance their object localization accuracy, yet dense CRF inference is computationally expensive. We propose replacing the fully-connected CRF with domain transform (DT), a modern edge-preserving filtering method in which the amount of smoothing is controlled by a reference edge map. Domain transform filtering is several times faster than dense CRF inference and we show that it yields comparable semantic segmentation results, accurately capturing object boundaries. Importantly, our formulation allows learning the reference edge map from intermediate CNN features instead of using the image gradient magnitude as in standard DT filtering. This produces task-specific edges in an end-to-end trainable system optimizing the target semantic segmentation quality.

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