It is a time-consuming and tedious work for manually colorizing anime line drawing images, which is an essential stage in cartoon animation creation pipeline. Reference-based line drawing colorization is a challenging task that relies on the precise cross-domain long-range dependency modelling between the line drawing and reference image. Existing learning methods still utilize generative adversarial networks (GANs) as one key module of their model architecture. In this paper, we propose a novel method called AnimeDiffusion using diffusion models that performs anime face line drawing colorization automatically. To the best of our knowledge, this is the first diffusion model tailored for anime content creation. In order to solve the huge training consumption problem of diffusion models, we design a hybrid training strategy, first pre-training a diffusion model with classifier-free guidance and then fine-tuning it with image reconstruction guidance. We find that with a few iterations of fine-tuning, the model shows wonderful colorization performance, as illustrated in Fig. 1. For training AnimeDiffusion, we conduct an anime face line drawing colorization benchmark dataset, which contains 31696 training data and 579 testing data. We hope this dataset can fill the gap of no available high resolution anime face dataset for colorization method evaluation. Through multiple quantitative metrics evaluated on our dataset and a user study, we demonstrate AnimeDiffusion outperforms state-of-the-art GANs-based models for anime face line drawing colorization. We also collaborate with professional artists to test and apply our AnimeDiffusion for their creation work. We release our code on https://github.com/xq-meng/AnimeDiffusion.
翻译:手动将动漫线条画进行彩色化是一项耗时且繁琐的工作,它是卡通动画制作流程中必不可少的阶段。基于参考图像的线条画彩色化是一项具有挑战性的任务,它依赖于线条画和参考图像之间精确的跨域长程依赖建模。现有的学习方法仍然利用生成对抗网络(GANs)作为其模型架构的关键模块。在本文中,我们提出了一种名为AnimeDiffusion的新方法,该方法使用扩散模型自动执行动漫人脸线条画彩色化。据我们所知,这是专为动漫内容创作量身定制的第一个扩散模型。为了解决扩散模型的大规模训练问题,我们设计了一种混合训练策略,首先以无分类器引导进行扩散模型的预训练,然后再以图像重建引导进行微调。我们发现,经过少量的微调迭代之后,模型展现了出色的彩色化性能,如图1所示。为训练AnimeDiffusion,我们进行了一项动漫人脸线条画彩色化基准数据集,其中包含31696个训练数据和579个测试数据。我们希望这个数据集可以填补没有可用的高分辨率动漫人脸数据集进行彩色化方法评估的空白。通过在我们的数据集上进行多个定量指标的评估和用户调查,我们证明AnimeDiffusion在动漫人脸线条画彩色化方面优于现有的基于GANs的模型。我们还与专业艺术家合作测试和应用我们的AnimeDiffusion。我们在https://github.com/xq-meng/AnimeDiffusion上发布了我们的代码。