Neural painting refers to the procedure of producing a series of strokes for a given image and non-photo-realistically recreating it using neural networks. While reinforcement learning (RL) based agents can generate a stroke sequence step by step for this task, it is not easy to train a stable RL agent. On the other hand, stroke optimization methods search for a set of stroke parameters iteratively in a large search space; such low efficiency significantly limits their prevalence and practicality. Different from previous methods, in this paper, we formulate the task as a set prediction problem and propose a novel Transformer-based framework, dubbed Paint Transformer, to predict the parameters of a stroke set with a feed forward network. This way, our model can generate a set of strokes in parallel and obtain the final painting of size 512 * 512 in near real time. More importantly, since there is no dataset available for training the Paint Transformer, we devise a self-training pipeline such that it can be trained without any off-the-shelf dataset while still achieving excellent generalization capability. Experiments demonstrate that our method achieves better painting performance than previous ones with cheaper training and inference costs. Codes and models are available.

本文提出了一种名为 Paint Transformer 的基于 Transformer 结构的神经网络框架，通过一个前馈网络来预测笔画集合的参数，从而实现在短时间内生成一个512 * 512的绘画。此外，作者设计了一个自学习流程，使其可以在没有任何预训练数据的情况下进行训练，并取得了比以往更好的绘画性能。

画笔变换器: 带有笔触预测的前馈神经绘画