arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2011.07466cs.CVcs.LGstat.ML
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连续条件生成对抗网络:新型经验损失与标签输入机制

Continuous Conditional Generative Adversarial Networks: Novel Empirical Losses and Label Input Mechanisms

University of British Columbia(不列颠哥伦比亚大学)

Xin Ding, Yongwei Wang, Zuheng Xu, William J. Welch, Z. Jane Wang

AI总结:

本文提出连续条件生成对抗网络CcGAN,通过重构经验损失并提出朴素与改进标签输入方法,解决以连续回归标签为条件的图像生成问题,并在多个数据集上显著优于现有cGAN。

摘要:

本文提出了连续条件生成对抗网络(CcGAN),这是首个以连续标量条件(称为回归标签)为条件的图像生成模型。现有的条件生成对抗网络(cGAN)主要针对类别条件(如类别标签)设计;以回归标签为条件在数学上具有本质区别,并引发两个基本问题:(P1)由于某些回归标签对应的真实图像可能非常少(甚至为零),最小化现有cGAN损失的经验版本(即经验cGAN损失)在实践中往往失败;(P2)由于回归标签是标量且无限多,传统的标签输入方法并不适用。所提出的CcGAN分别通过以下方式解决上述问题:(S1)重新构造现有经验cGAN损失,使其适用于连续场景;(S2)提出一种朴素标签输入(NLI)方法和一种改进标签输入(ILI)方法,将回归标签融入生成器和判别器。(S1)中的重构产生了两种新的经验判别器损失,分别称为硬邻域判别器损失(HVDL)和软邻域判别器损失(SVDL),以及一种新的经验生成器损失。本文在温和假设下推导了使用HVDL和SVDL训练的判别器的误差界。针对这一连续场景,还提出了两个新的基准数据集(RC-49和Cell-200)以及一种新的评估指标(滑动Fréchet Inception Distance)。我们在Circular 2-D Gaussians、RC-49、UTKFace、Cell-200和Steering Angle数据集上的实验表明,CcGAN能够从以给定回归标签为条件的图像分布中生成多样且高质量的样本。此外,在这些实验中,CcGAN在视觉和定量两方面都显著优于cGAN。

英文摘要:

This work proposes the continuous conditional generative adversarial network (CcGAN), the first generative model for image generation conditional on continuous, scalar conditions (termed regression labels). Existing conditional GANs (cGANs) are mainly designed for categorical conditions (eg, class labels); conditioning on regression labels is mathematically distinct and raises two fundamental problems:(P1) Since there may be very few (even zero) real images for some regression labels, minimizing existing empirical versions of cGAN losses (aka empirical cGAN losses) often fails in practice;(P2) Since regression labels are scalar and infinitely many, conventional label input methods are not applicable. The proposed CcGAN solves the above problems, respectively, by (S1) reformulating existing empirical cGAN losses to be appropriate for the continuous scenario; and (S2) proposing a naive label input (NLI) method and an improved label input (ILI) method to incorporate regression labels into the generator and the discriminator. The reformulation in (S1) leads to two novel empirical discriminator losses, termed the hard vicinal discriminator loss (HVDL) and the soft vicinal discriminator loss (SVDL) respectively, and a novel empirical generator loss. The error bounds of a discriminator trained with HVDL and SVDL are derived under mild assumptions in this work. Two new benchmark datasets (RC-49 and Cell-200) and a novel evaluation metric (Sliding Fréchet Inception Distance) are also proposed for this continuous scenario. Our experiments on the Circular 2-D Gaussians, RC-49, UTKFace, Cell-200, and Steering Angle datasets show that CcGAN is able to generate diverse, high-quality samples from the image distribution conditional on a given regression label. Moreover, in these experiments, CcGAN substantially outperforms cGAN both visually and quantitatively.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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