Abstract

Despite the great advances in visual recognition, it has been witnessed that recognition models trained on clean images of common datasets are not robust against distorted images in the real world. To tackle this issue, we present a Universal and Recognition-friendly Image Enhancement network, dubbed URIE, which is attached in front of existing recognition models and enhances distorted input to improve their performance without retraining them. URIE is universal in that it aims to handle various factors of image degradation and to be incorporated with any arbitrary recognition models. Also, it is recognition-friendly since it is optimized to improve the robustness of following recognition models, instead of perceptual quality of output image. Our experiments demonstrate that URIE can handle various and latent image distortionsand improve the performance of existing models for five diverse recognition tasks where input images are degraded.

Overall architecture

Figure 1. Overall architecture of URIE. The Selective Enhancement Modules (SEM) are indicated by gray rectangles. Details of these modules are illustrated in Fig. 2.

Selective Enhancement Module (SEM)

Figure 2. Details of SEM. ⊕ and ⊗ indicate element-wise summation and multiplication between feature maps, respectively

How our model works

Figure 3. Example outputs of URIE. (a) Distorted input images. (b) Outputs of URIE. (c) Ground-truth images. (d) Magnitudes of per-pixel intensity change by URIE.

Quantitative results

1. Classification accuracy on the ImageNet dataset

Table 1. Classification accuracy on the ImageNet dataset. The numbers in parentheses indicate the differences from the baseline. V16, R50, and R101 denote VGG-16, ResNet50, and ResNet-101, respectively.


2. Classification accuracy on the CUB dataset

Table 2. Classification accuracy on the CUB dataset. The numbers in parentheses indicate the differences from the baseline. V16, R50, and R101 denote VGG-16, ResNet50, and ResNet-101, respectively.


3. Object detection performance on the VOC 2007 dataset

Table 3. Object detection performance of SSD 300 in mAP (%) on the VOC 2007 dataset. The numbers in parentheses indicate the differences from the baseline.


4. Semantic segmentation performance on the VOC 2012 dataset

Table 4. Semantic segmentation performance of DeepLab v3 in mIoU (%) on the VOC 2012 dataset. The numbers in parentheses indicate the differences from the baseline.


5. Classification accuracy on the Haze-20 dataset

Table 5. Accuracy of the ResNet-50 classifier on the Haze-20 and HazeClear-20 datasets. The numbers in parentheses indicate the differences from the baseline.

Qualitative results

1. Qualitative results on the CUB dataset.

Figure 4. Qualitative results on the CUB dataset. (a) Input distorted images. (b) OWAN. (c) URIE-MSE. (d) URIE. (e) Ground-truth images. For all images, their grad-CAMs drawn by the ResNet-50 classifier are presented alongside. Examples in the first row are degraded by seen corruptions and the others are by unseen corruptions.


2. Qualitative results on the VOC07 dataset.

Figure 5. Qualitative results of SSD 300 on the VOC 2007 dataset. (a) Corrupted input. (b) OWAN. (c) URIE-MSE. (d) URIE. (e) Ground-truth. Examples in the top three rows are degraded by seen corruptions and the others are by unseen corruptions.


3. Qualitative results on the VOC2012 dataset.

Figure 6. Qualitative results of DeepLab v3 on the VOC 2012 dataset. (a) Corrupted input. (b) OWAN. (c) URIE-MSE. (d) URIE. (e) Ground-truth. Examples in the top two rows are degraded by seen corruptions and the others are by unseen corruptions.


4. Qualitative results on the Haze-20 dataset.

Figure 7. Qualitative results on the Haze-20 dataset. (a) Corrupted input. (b) OWAN. (c) URIE-MSE. (d) URIE. Top-1 prediction of the ResNet-50 classifier together with its confidence score and grad-CAM are presented alongside per example.

Paper

URIE: Universal Image Enhancement for Visual Recognition in the Wild
Taeyoung Son, Juwon Kang, Namyup Kim, Sunghyun Cho and Suha Kwak
ECCV, 2020
[arXiv] [Bibtex]

Code

Check our GitHub repository: [github]