Face verification focuses on the problem of making machines automatically determine whether a pair of face images refer to the same identity. As a fundamental research task, its development benefits various real-world applications, ranging from security surveillance to credit investigation. Over the past decades, massive face verification methods have achieved significant progress [Sun, Wang, and Tang2013, Taigman et al.2014, Sun et al.2014, Jing et al.2016, Zhang et al.2016, He et al.2017, Huang et al.2017], especially the ones profiting by the recently raised deep networks. Nevertheless, there are still challenges remaining as bottlenecks in the real-world applications, such as pose [Huang et al.2017], NIR-VIS [He et al.2017]
and makeup changes, which are often summarized as heterogeneous tasks. Due to the wide applications of facial cosmetics, the verification task of face images before and after makeup has drawn much attention in the computer vision society.
The history of cosmetics can be traced back to at least ancient Egypt [Burlando et al.2010]. Nowadays wearing makeup is well accepted in the daily life, and is even regarded as a basic courtesy on many important occasions. With appropriate cosmetic products, one can easily smooth skin, alter lip colour, change the shape of eyebrows, and accentuate eye regions. All these operations are often used to hide facial flaws and improve perceived attractiveness. But in the meanwhile, they also bring about remarkable facial appearance changes as exhibited in Figure 1, resulting in both global and local appearance discrepancies between the images with and without makeup. Most of the existing face verification methods rely much on the various cues and information captured by the effective appearance features. These methods inherently lack robustness over the application of makeup that is non-permanent as well as miscellaneous. Recent study in [Dantcheva, Chen, and Ross2012] has claimed that the application of facial cosmetics decreases the performance of both commercial and academic face verification approaches significantly.
In contrast to the mentioned schemes, we consider from a new perspective and propose to settle the makeup-invariant face verification problem via a learning from generation framework. This framework simultaneously considers makeup removal and face verification, and is implemented by an end-to-end bi-level adversarial network (BLAN). It has the capacity of removing the cosmetics on a face image with makeup, namely synthesizing an appealing non-makeup image with identity information preserved, effectively reducing the adverse impact of facial makeup. It promotes the verification performance of faces before and after makeup by imposing adversarial schemes on both pixel level and feature level. Considering the variety and temporality characters of makeup, we first push the images to a uniform cosmetic status, the non-makeup status, by a Generative Adversarial Network (GAN) [Goodfellow et al.2014]
. And then, deep features are extracted from the synthesized non-makeup faces for further verification task. As is illustrated in Figure2, the two steps above are not detached but integrated, for the adversarial loss on pixel level profits to generate perceptually better faces and the adversarial loss on feature level is employed to enhance the identity preservation. Moreover, we also make the reconstruction well constrained via incorporating multiple priors such as symmetry and edges. Experiments are conducted on three makeup datasets and favorable results demonstrate the efficiency of our framework.
The major contributions of our work are as follows.
We propose a learning from generation framework for makeup-invariant face verification. To the best of our knowledge, our framework is the first to account for the possibility of accomplishing the makeup-invariant verification task with synthesized faces.
The bi-level adversarial network architecture is newly set up for our proposed framework. There are two adversarial schemes on different levels, with the one on pixel level contributing to reconstruct appealing face images and the other on feature level serving for identity maintenance.
To faithfully retain the characteristic facial structure of a certain individual, we affiliate multiple reconstruction losses in the network. Both convincingly quantitative and perceptual outcomes are achieved.
As always, the face verification problem has attracted extensive attention and witnessed great progress. Recent impressive works are mostly based on deep networks. Sun et al. [Sun, Wang, and Tang2013]
proposed a hybrid convolutional network - Restricted Boltzmann Machine (ConvNet-RBM) model, which directly learns relational visual features from raw pixels of face pairs, for verification task in wild conditions. The Deepface architecture was expounded in[Taigman et al.2014] to effectively leverage a very large labeled dataset of faces for obtaining a representation with generalization. It also involved an alignment system based on explicit 3D modeling. The Deep IDentification-verification features (DeepID2) were learned in [Sun et al.2014] which uses both identification and verification information as supervision. With the further development of the face verification task, there are approaches customized for some certain conditions. For instance, Zhang et al. [Zhang et al.2016] aimed at facilitating the verification performance between the clean face images and the corrupted ID photos. Huang et al. [Huang et al.2017] attempted to accomplish the recognition task of face images under a large pose. In this paper, we focus on the negative effects of the application of cosmetics over the verification systems, which is one of the most practical issue to be resolved in the real-world applications.
Makeup related studies, such as makeup recommendation [Alashkar et al.2017], have become more popular than ever. However, relatively less articles pay attention on the challenge of makeup impact on face verification. Among these existing works, most of them contrive to design a feature scheme artificially to impel the pair images of the same identity to have the maximum correlation. To increase the similarity between face images of the same person, a meta subspace learning method was proposed in [Hu et al.2013]. Guo et al. [Guo, Wen, and Yan2014]
explored the correlation mapping between makeup and non-makeup faces on features extracted from local patches. Chen et al.[Chen, Dantcheva, and Ross2016] introduced a patch-based ensemble learning method that uses subspaces generated by sampling patches from before and after makeup face images. A hierarchical feature learning framework was demonstrated in [Zheng and Kambhamettu2017]
that seeks for transformations of multi-level features. In addition, Convolutional Neural Network (CNN) based schemes have been recently developed. For example,[Sun et al.2017] proposed to pre-train network on the free videos and fine-tune it on small makeup and non-makeup datasets.
Generative Adversarial Network
). It corresponds to a min-max two-player game which ensures its ability of commendably estimating the target distribution and generating images that does not exist in the training set. Thereafter, multifariously modified GANs are explored, especially the ones in conditional settings. Pathak et al.[Pathak et al.2016]
proposed Context Encoders to cope with the image inpainting and Ledig et al.[Ledig et al.2016]
applied GAN to super-resolution. The work in[Isola et al.2016]
investigated conditional adversarial networks as a solution to image-to-image translation problems. A Two-Pathway Generative Adversarial Network (TP-GAN) was established for photorealistic frontal view synthesis.
Bi-level Adversarial Network
To refrain from the influence induced by facial makeup, we propose to synthesize a non-makeup image from a face image with makeup first, via a generative network. And then, a deep feature is extracted from the synthesized to further accomplish the verification task. We depict the overall structure of the proposed network in Figure 2, with the details described below.
Notation and Overview
The original GAN in [Goodfellow et al.2014] takes random noise as input and maps it to output images in domains such as MNIST. Different from it, we take images as input and set up our network as a conditional GAN. The generator denoted as aims at learning a mapping from elements in domain (with makeup) to elements in domain (without makeup): , where the superscripts stand for the image size. If not constrained, the learned mapping can be arbitrary. Whereas, our network is tailored for further face verification application. And the two key intuitions are that the non-makeup facial image should be well synthesized and that the input and output of should be identity invariant. We thus impose the constraint on through introducing two adversarial discriminators on pixel level and feature level respectively.
During the training phase, image pairs with identity information are required. Some existing conditional GANs based methods [Pathak et al.2016, Isola et al.2016, Huang et al.2017] have found that the generator is enhanced by adding a more traditional loss (e.g., L1 and L2 distances) to the GAN objective. The reason lies in that the generator is required to produce images close to the ground truth, not just to fool the discriminators in a conditional GAN. We thus enrich our training losses with some reconstruction items. Suppose that the training set consists of training pairs, the generator receives four kinds of losses for parameter updating: two reconstruction loss denoted by and , and two adversarial losses denoted by and in the Figure 2. And the generator parameters are obtained by the solving the following optimization:
where the contributions of the losses are weighted by , and . And the details of each loss will be discussed in the following section. As for both the discriminators, we apply the standard GAN discriminator loss formulated in Equation 2 and 3, since their duty of telling the fake from the real remains unchanged.
Here, the operation of represents the feature extraction. When training the network, we follow the behavior in [Goodfellow et al.2014] and alternately optimize the min-max problem described above. By this means, the generator is constantly driven to produce high-quality images that agree with the target distribution or the ground truth. Specifically, the synthesized non-makeup facial images from makeup ones will become more and more reliable and finally benefit the verification task.
The generator in our proposed BLAN aims to learn a desirable mapping between facial images with and without makeup of the same person. An encoder-decoder network [Hinton and Salakhutdinov2006] can carry the duty out well and has been widely utilized in existing conditional GANs [Pathak et al.2016, Wang and Gupta2016, Huang et al.2017, Kim et al.2017]. However, we notice an inherent property here in our task that the input and output of the generator are roughly aligned and share much of the information, both locally and globally. In this situation, a simple encoder-decoder network appears to be insufficient. The reason is that all the information in the input image has to go through the intermediate bottleneck whose size is usually much smaller than the input. This fact determines much of the low level priors captured by the first few layers would be abandoned before the bottleneck, thus makes the encoder-decoder network lack the ability to effectively take advantage of the low level information.
To address a similar problem in biomedical image segmentation, Ronneberger et al. [Ronneberger, Fischer, and Brox2015] proposed an architecture named “U-net” to directly deliver context information to the corresponding layers with higher resolution, yielding the network shape of “U”. Thereafter, Isola et al. [Isola et al.2016] applied a semblable network to its generator for solving the image-to-image translation problem. Inspired by these works, we also adopt a network with skip connections to let the information acquired by the encoder benefit the output of decoder as much as possible. In specific, we follow the settings in [Isola et al.2016] and concatenate the duplicate of layer straight to layer , with denoting the total layer amount of the generator.
In the sections above, we have elaborated the overall structure and the generator architecture we employ. This part will focus on the four kinds of losses that the generator receive, which has been briefly described in Equation 1. Besides the double adversarial losses, we also integrate various perceptual losses in to guarantee the quality of generated images. Particularly, the reconstruction loss is composed of three subordinates — a pixel-wise loss, a symmetry loss and a first-order loss. In the following, we will discuss them in details one by one.
It has been mentioned that incorporating traditional losses helps to improve the outcome quality. There are generally two options for pixel wise loss — L1 distance or L2 distance. Since L1 distance is generally deemed to arouse less blur than L2 distance, we formulate the pixel-wise loss function as
Given the paired data , the pixel-wise loss continuously push the synthesized non-makeup facial image to be as close to the ground truth as possible. In our experiments, we also find that the pixel-wise loss helps to accelerate parameters convergence in some degree.
Although the pixel-wise loss in form of L1 distance would bring about blurry results, the adversarial scheme in GANs can alleviate it to some extent. However, this is based on the premise that there is adequate training data to learn a qualified discriminator, while the scale of existing makeup datasets are rather limited. To further cope with the blurring problem, we propose to train our network with the help of a first-order loss, which takes the form of
where stands for the (i,j) pixel of the synthesized image . The first-order loss can also be referred as the edge loss, for it aims at fully explore the gradient priors provided in . It actually needs to calculate the edges in images and then drives the edge image of the synthesized face to be close to the edge image of the ground truth.
As one of the most prominent characteristics of human faces, the symmetric structure is well exploited in many previous face related studies. Here in our network, we take it into consideration as well and imposes a symmetric constraint to guarantee the essential legitimacy of the synthesized face structure. The corresponding symmetry loss is calculated by
The responsibility of the discriminator on the pixel level is to distinguish real non-make facial images from the fake one and it serves as a supervision to produce relatively more pleasing synthesized results. Its corresponding adversarial loss on the generator is
In addition to removing makeups, we also expect the synthesized images to facilitate the verification performance across makeup status. Since the verification task is accomplished on image features (e.g. Light CNN [Wu et al.2015] feature in our experiments), the key issue is converted to produce images with high quality features, which is crucial for identity preserving. To this end, we propose to further cascade an adversarial network centering on the feature level at the end of the original conditional GAN model. The discriminator is in charge of differentiating between features from real non-makeup images and fake ones, driving to synthesizing images with features close to the target. We formulate the adversarial loss on the feature level as
Similar to the scheme on the pixel level, we incorporate a reconstruction loss with the adversarial loss which takes the following form:
Inspired by the concepts in Conditional Random Field [Lafferty, McCallum, and Pereira2001], we address an assumption on deciding whether the input of the discriminator is real or fake: in a certain image, pixels that are apart from each other are relatively independent. Based on the assumption, we first divide an image into patches without overlapping. And then the discriminator runs on each patch to obtain a score indicating whether this part of the image is real or not. Thus for each input image, the outcome of
is a probability map containingelements. In our experiments, we empirically set . By this means, is able to pay more attention to local regions instead of the whole image. Additionally, the operation simplifies the required structure of and significantly reduces the parameter amount in the network, which is friendly to small datasets. As for the discriminator on the feature level (i.e. ), we concisely set it up with two linear layers, considering the conflict between the complexity of the BLAN structure and the fact of limited available training data.
Experiments and Analysis
We evaluate our proposed BLAN on three makeup datasets. Both visualized results of synthesized non-makeup images and quantitative verification performance are present in this section. Furthermore, we explore the effects of all losses and report them in the ablation studies. The overall results demonstrate that our framework is able to achieve state-of-the-art verification accuracy across makeup status, with appealing identity-preserved non-makeup images synthesized from the ones with makeup.
Dataset 1: This dataset is collected in [Guo, Wen, and Yan2014] and contains face images of female individuals. For each individual, there are two facial images — one with makeup and the other without. The females span mainly over Asian and Caucasian descents. Dataset 2: Assembled in [Sun et al.2017], there are pairs of images with and without makeup, each pair corresponding to a female individual. Dataset 3 (FAM) [Hu et al.2013]: Different from the other two datasets, FAM involves males and females, with images belonging to subjects in total. It is worthy noticing that all these images are not acquired under a controlled condition for they are collected from the Internet. Thus there also exist pose changes, expression variations, occlusion and other noises in these datasets except for makeup alteration. Some sample images from the three datasets are showed in Figure 3.
Following the settings in [Guo, Wen, and Yan2014, Sun et al.2017, Hu et al.2013], we adopt five-fold cross validation in our experiments. In each round, we use about paired data for training and the rest for testing, no overlap between training set and testing set. All the positive pairs are involved in the testing phase and equal pairs of negative samples are randomly selected. Hence, taking Dataset 1 as an example, there are about pairs of faces for testing each time. We report the rank-1 average accuracy over the five folds as quantitative evaluation.
In our experiments, all the input images are resized to and the generator output synthetic images of the same size. BLAN is composed of a generator , two discriminator and , and a feature extractor Light CNN. The Light CNN used for feature extracting is pre-trained on MS-Celeb-1M [Guo et al.2016] without fine-tuning on makeup datasets. is an encoder-decoder network with U-Net structure and consists of
Convolution-BatchNorm-ReLU layers. It contains aboutk parameters and about G FLOPS. is a network with
convolution layers followed by a Sigmoid function. It contains aboutk parameters and G FLOPS. is made of fc layers and contains about
k parameters. We accomplish our network on PyTorch[Paszke, Gross, and Chintala2017]. It takes about hours to train BLAN on Dataset 1, with a learning rate of . Data augmentation of mirroring images is also adopted in the training phase. Considering the limited number of images in Dataset 2, we first train BLAN on Dataset 1 and then fine-tune it on Dataset 2 in our experiments. As for the loss weights, we empirically set , and . In particular, we also set a weight of to the edge loss and to the symmetry loss inside .
Comparisons with Existing Methods
|Dataset 1||[Guo, Wen, and Yan2014]|
|[Sun et al.2017]|
|Dataset 2||[Sun et al.2017]|
|FAM||[Nguyen and Bai2010]|
|[Hu et al.2013]|
The ultimate goal of our proposed BLAN is to facilitate face verification performance across makeup status by generating non-makeup facial images. We demonstrate the effectiveness of BLAN by conducting verification task on the mentioned three makeup datasets. The results on VGG [Simonyan and Zisserman2015] and Light CNN [Wu et al.2015] serve as baselines. Particularly, we adopt VGG-16 and Light CNN without any fine-tuning on the makeup datasets. In these experiments, we extract deep features from images with and without makeup via the corresponding networks and directly use them for matching evaluation. While in the BLAN experiment, a non-makeup image is first produced by the generator for each makeup image. Then the generated non-makeup image is sent to Light CNN for deep feature extraction. It should be noted that our method is actually accomplishing verification task on synthetic images, which is of significant progress.
We compare the rank-1 verification accuracy with some existing methods in Table 1 and report the true positive rate in Table 2. The similarity metric used in all experiments is cosine distance. Except for the mentioned baselines, the methods listed are all tailored for makeup-invariant face verification. Among them, the works in [Guo, Wen, and Yan2014], [Nguyen and Bai2010] and [Hu et al.2013] explore the correlation between images of a certain identity with and without makeup in traditional ways, while the approach in [Sun et al.2017] is based on deep networks. From Table 1, we can observe that our proposed BLAN brings prominent improvement to rank-1 accuracy comparing with existing makeup-invariant schemes, both traditional and deep ones. In specific, a boost of at least is achieved on each dataset. It demonstrates that our architecture is able to achieve state-of-the-art performance on the datasets. Additionally, it is worth noticing that both VGG and Light CNN are trained on much larger datasets than the makeup datasets. Their produced deep features are thus rather powerful, resulting in much higher accuracies than the traditional schemes. Compared the feature extraction processes in BLAN and in Light CNN, the only difference lies in the input. Even though, our network still outperforms the two baselines. These phenomena consistently validate that our learning from generation framework has the ability of promote verification performance by alleviating impact from makeup.
Synthetic Non-Makeup Images
For the existing makeup-invariant face verification methods we discussed, none of them has the capacity of generating non-makeup images from that with makeup. In contrast to them, we propose to extract deep features directly from synthetic non-makeup images for face verification. To evaluate our BLAN perceptually, we exhibit some synthetic samples in Figure 4. Observing the second rows in these figures, we can find that both holistic face structure and most local attributes of the original faces are kept. The reason is that in addition to the discriminator on pixel level, we propose to impose another discriminator on feature level to maintain the identity prior as well as facial structure.
Different makeup datasets have different characteristics. Dataset 1 and Dataset 2 only contain female subjects and the paired images have higher resolution compared with FAM. Thus, BLAN achieves perceptually better synthetic images and results in higher verification accuracy on these datasets. In contrast, more than of the subjects are male in FAM. We show both male and female results of BLAN in Figure 4. The makeup removing results of males are not so satisfied as that of females. For male individuals, the gap between makeup images and non-makeup ones are relatively narrower than the females and the training data of males is much less than the females, which are determined by the fact that males trend to wear less makeup in reality.
However, we also notice that there exists blurs in our synthetic non-makeup images compared with ground truth. And the clarity of facial component outlines, e.g. eyes contour, is not so compelling as expected. The reasons lie in multiple folds. 1) In reconstruction loss on pixel level, we adopt L1 distance. It has been reported in [Isola et al.2016] and [Huang et al.2017] that L1 distance loss in generator will bring about image blurs for it leads to overly smooth results. Even though there are adversarial networks, the overly smooth problem can not be swept away. 2) We merely utilize the data from the three makeup datasets to train BLAN, without any help from other data. Compared with other face related datasets, the data sizes of these makeup datasets are rather limited. It consequently decreases the training quality of the network. 3) As has been introduced in Section Datasets, all the paired images are collected from the Internet. In other words, the images are not acquired under a controlled condition. Even the facial key points are not strictly aligned as standard facial datasets. We present some images pairs with pose, expression and occlusion changes and their synthetic non-makeup results in Figure 5. These changes will severely hinder the network training and thus impact the generated image quality.
To fully explore the contribution of each loss, we conduct experiments on different architecture variants of BLAN. The quantitative verification results are reported in Table 3 for comprehensive comparison. We remove one of the losses in generator training each time and examine the corresponding accuracy change. As expected, BLAN with all the losses achieves the best accuracy. It is evident that and bring the greatest declines, indicating the effectiveness and importance of adversarial network on feature level. As for and , they also help to promote the performance, though not as much remarkable as the fore discussed two losses. We also present visualization samples of each variant in Figure 6. The generated images without the edge loss and the symmetry loss tend to suffer from more unnatural artifacts. And the absence of adversarial loss on feature level causes serve blur to the synthesized results. Finally, contributes most to the identity preservation, as can be distinctly observed by comparing the last three rows in Figure 6.
In this paper, we have proposed a new learning from generation framework to address the makeup problem in face verification. A synthesized non-makeup image is generated with its identity prior well preserved from a makeup image. And then, the produced non-makeup images are used for face verification, which effectively bypasses the negative impact incurred by cosmetics. Specifically, we have proposed a novel architecture, named bi-level adversarial network (BLAN), where there is one discriminator on pixel level to distinguish real non-makeup images from fake ones and another discriminator on feature level to determine whether a feature vector is from a target image. To further improve the quality of our synthesized images, reconstruction losses have been also employed for training the generator. Extensive experiments on three makeup datasets show that our network not only generates pleasing non-makeup images but also achieves state-of-the-art verification accuracy under makeup conditions.
This work is partially funded by the State Key Development Program (Grant No. 2016YFB1001001) and National Natural Science Foundation of China (Grant No.61473289, 61622310).
[Alashkar et al.2017]
Alashkar, T.; Jiang, S.; Wang, S.; and Fu, Y.
Examples-rules guided deep neural network for makeup recommendation.
The Thirty-First AAAI Conference on Artificial Intelligence, 941–947. AAAI Press.
- [Burlando et al.2010] Burlando, B.; Verotta, L.; Cornara, L.; and Bottini-Massa, E. 2010. Herbal principles in cosmetics: Properties and mechanisms of action. CRC Press.
[Chen, Dantcheva, and
Chen, C.; Dantcheva, A.; and Ross, A.
An ensemble of patch-based subspaces for makeup-robust face recognition.Information Fusion 32:80–92.
- [Dantcheva, Chen, and Ross2012] Dantcheva, A.; Chen, C.; and Ross, A. 2012. Can facial cosmetics affect the matching accuracy of face recognition systems? In the Fifth International Conference on Biometrics: Theory, Applications and Systems, 391–398. IEEE.
- [Goodfellow et al.2014] Goodfellow, I.; Pouget-Abadie, J.; Mirza, M.; Xu, B.; Warde-Farley, D.; Ozair, S.; Courville, A.; and Bengio, Y. 2014. Generative adversarial nets. In Advances in neural information processing systems, 2672–2680.
- [Guo et al.2016] Guo, Y.; Zhang, L.; Hu, Y.; He, X.; and Gao, J. 2016. Ms-celeb-1m: A dataset and benchmark for large-scale face recognition. In European Conference on Computer Vision, 87–102. Springer.
- [Guo, Wen, and Yan2014] Guo, G.; Wen, L.; and Yan, S. 2014. Face authentication with makeup changes. IEEE Transactions on Circuits and Systems for Video Technology 24(5):814–825.
- [He et al.2017] He, R.; Wu, X.; Sun, Z.; and Tan, T. 2017. Learning invariant deep representation for nir-vis face recognition. In The Thirty-First AAAI Conference on Artificial Intelligence, 2000–2006. AAAI Press.
- [Hinton and Salakhutdinov2006] Hinton, G. E., and Salakhutdinov, R. R. 2006. Reducing the dimensionality of data with neural networks. science 313(5786):504–507.
- [Hu et al.2013] Hu, J.; Ge, Y.; Lu, J.; and Feng, X. 2013. Makeup-robust face verification. In International Conference on Acoustics, Speech and Signal Processing, 2342–2346.
- [Hu et al.2017] Hu, X.; Zhao, X.; Huang, K.; and Tan, T. 2017. Adversarial learning based saliency detection. In The 4th Asian Conference on Pattern Recognition.
- [Huang et al.2017] Huang, R.; Zhang, S.; Li, T.; and He, R. 2017. Beyond face rotation: Global and local perception gan for photorealistic and identity preserving frontal view synthesis. arXiv preprint arXiv:1704.04086.
- [Isola et al.2016] Isola, P.; Zhu, J.-Y.; Zhou, T.; and Efros, A. A. 2016. Image-to-image translation with conditional adversarial networks. arXiv preprint arXiv:1611.07004.
- [Jing et al.2016] Jing, X.-Y.; Wu, F.; Zhu, X.; Dong, X.; Ma, F.; and Li, Z. 2016. Multi-spectral low-rank structured dictionary learning for face recognition. Pattern Recognition 59:14–25.
- [Kim et al.2017] Kim, T.; Cha, M.; Kim, H.; Lee, J.; and Kim, J. 2017. Learning to discover cross-domain relations with generative adversarial networks. arXiv preprint arXiv:1703.05192.
[Lafferty, McCallum, and
Lafferty, J.; McCallum, A.; and Pereira, F.
Conditional random fields: Probabilistic models for segmenting and
labeling sequence data.
the 18th International Conference on Machine Learning, volume 1, 282–289.
- [Ledig et al.2016] Ledig, C.; Theis, L.; Huszár, F.; Caballero, J.; Cunningham, A.; Acosta, A.; Aitken, A.; Tejani, A.; Totz, J.; Wang, Z.; et al. 2016. Photo-realistic single image super-resolution using a generative adversarial network. arXiv preprint arXiv:1609.04802.
- [Nguyen and Bai2010] Nguyen, H. V., and Bai, L. 2010. Cosine similarity metric learning for face verification. In Asian Conference on Computer Vision, 709–720. Springer.
- [Paszke, Gross, and Chintala2017] Paszke, A.; Gross, S.; and Chintala, S. 2017. Pytorch. https://github.com/pytorch/pytorch.
- [Pathak et al.2016] Pathak, D.; Krahenbuhl, P.; Donahue, J.; Darrell, T.; and Efros, A. A. 2016. Context encoders: Feature learning by inpainting. In the IEEE Conference on Computer Vision and Pattern Recognition, 2536–2544.
- [Ronneberger, Fischer, and Brox2015] Ronneberger, O.; Fischer, P.; and Brox, T. 2015. U-net: Convolutional networks for biomedical image segmentation. In International Conference on Medical Image Computing and Computer-Assisted Intervention, 234–241. Springer.
- [Simonyan and Zisserman2015] Simonyan, K., and Zisserman, A. 2015. Very deep convolutional networks for large-scale image recognition. In Proceedings of the 3rd International Conference on Learning Representations.
- [Sun et al.2014] Sun, Y.; Chen, Y.; Wang, X.; and Tang, X. 2014. Deep learning face representation by joint identification-verification. In Advances in neural information processing systems, 1988–1996.
- [Sun et al.2017] Sun, Y.; Ren, L.; Wei, Z.; Liu, B.; Zhai, Y.; and Liu, S. 2017. A weakly supervised method for makeup-invariant face verification. Pattern Recognition 66:153–159.
- [Sun, Wang, and Tang2013] Sun, Y.; Wang, X.; and Tang, X. 2013. Hybrid deep learning for face verification. In the IEEE International Conference on Computer Vision, 1489–1496.
- [Taigman et al.2014] Taigman, Y.; Yang, M.; Ranzato, M.; and Wolf, L. 2014. Deepface: Closing the gap to human-level performance in face verification. In the IEEE Conference on Computer Vision and Pattern Recognition, 1701–1708.
- [Wang and Gupta2016] Wang, X., and Gupta, A. 2016. Generative image modeling using style and structure adversarial networks. In European Conference on Computer Vision, 318–335. Springer.
- [Wu et al.2015] Wu, X.; He, R.; Sun, Z.; and Tan, T. 2015. A light cnn for deep face representation with noisy labels. arXiv preprint arXiv:1511.02683.
- [Zhang et al.2016] Zhang, S.; He, R.; Sun, Z.; and Tan, T. 2016. Multi-task convnet for blind face inpainting with application to face verification. In International Conference on Biometrics, 1–8.
- [Zheng and Kambhamettu2017] Zheng, Z., and Kambhamettu, C. 2017. Multi-level feature learning for face recognition under makeup changes. In 12th IEEE International Conference on Automatic Face & Gesture Recognition, 918–923.