In image editing employing diffusion models, it is crucial to preserve the reconstruction quality of the original image while changing its style. Although existing methods ensure reconstruction quality through optimization, a drawback of these is the significant amount of time required for optimization. In this paper, we propose negative-prompt inversion, a method capable of achieving equivalent reconstruction solely through forward propagation without optimization, thereby enabling much faster editing processes. We experimentally demonstrate that the reconstruction quality of our method is comparable to that of existing methods, allowing for inversion at a resolution of 512 pixels and with 50 sampling steps within approximately 5 seconds, which is more than 30 times faster than null-text inversion. Reduction of the computation time by the proposed method further allows us to use a larger number of sampling steps in diffusion models to improve the reconstruction quality with a moderate increase in computation time.

翻译：在采用扩散模型进行图像编辑时，在改变图像风格的同时保持原始图像的重建质量至关重要。现有方法虽通过优化确保了重建质量，但存在优化耗时过长的缺陷。本文提出负提示反演方法，能够仅通过前向传播（无需优化）实现等效重建，从而大幅提升编辑速度。实验证明，本方法的重建质量与现有方法相当，可在约5秒内完成512像素分辨率、50步采样步数的反演，速度比空文本反演快30倍以上。该方法通过减少计算时间，还允许在扩散模型中采用更多采样步数，在计算时间适度增加的情况下提升重建质量。