Diffusion models (DMs) have been successfully applied to real image editing. These models typically invert images into latent noise vectors during the inversion process, and then edit them during the inference process. However, DMs often rely on the local linearization assumption, which assumes that the noise injected during the inversion process approximates the noise removed during the inference process. While DMs efficiently generate images under this assumption, it also accumulates errors during the diffusion process due to the assumption, ultimately negatively impacting the quality of real image reconstruction and editing. To address this issue, we propose a novel ERDDCI (Exact Reversible Diffusion via Dual-Chain Inversion). ERDDCI uses the new Dual-Chain Inversion (DCI) for joint inference to derive an exact reversible diffusion process. Using DCI, our method avoids the cumbersome optimization process in existing inversion approaches and achieves high-quality image editing. Additionally, to accommodate image operations under high guidance scales, we introduce a dynamic control strategy that enables more refined image reconstruction and editing. Our experiments demonstrate that ERDDCI significantly outperforms state-of-the-art methods in a 50-step diffusion process. It achieves rapid and precise image reconstruction with SSIM of 0.999 and LPIPS of 0.001, and delivers competitive results in image editing. The source code is available at: https://github.com/daii-y/ERDDCI.

The Reflow operation aims to straighten the inference trajectories of the rectified flow during training by constructing deterministic couplings between noises and images, thereby improving the quality of generated images in single-step or few-step generation. However, we identify critical limitations in Reflow, particularly its inability to rapidly generate high-quality images due to a distribution gap between images in its constructed deterministic couplings and real images. To address these shortcomings, we propose a novel alternative called Straighten Viscous Rectified Flow via Noise Optimization (VRFNO), which is a joint training framework integrating an encoder and a neural velocity field. VRFNO introduces two key innovations: (1) a historical velocity term that enhances trajectory distinction, enabling the model to more accurately predict the velocity of the current trajectory, and (2) the noise optimization through reparameterization to form optimized couplings with real images which are then utilized for training, effectively mitigating errors caused by Reflow's limitations. Comprehensive experiments on synthetic data and real datasets with varying resolutions show that VRFNO significantly mitigates the limitations of Reflow, achieving state-of-the-art performance in both one-step and few-step generation tasks.

With the rapid progress of diffusion-based Text-to-Image Generation (TIG), Text-to-Image Editing (TIE) has become increasingly important for enabling controllable visual content creation. A core challenge in TIE is generating text-guided edits while preserving the spatial structure of the original image. Recent methods attempt to address this by leveraging self-attention maps from diffusion models, as these encode rich spatial information. However, we identify two key limitations: (1) not all self-attention maps contribute meaningfully to spatial structure, and (2) over-reliance on them can suppress desired editing effects. To address this, we propose the Spatial Information Score (SIS), a novel metric that quantifies the spatial structure encoded in each self-attention map. Leveraging SIS, we develop Selective Self-Attention-based Image Manipulation (SSAIM), which selectively utilizes self-attention maps with effective spatial structure (high SIS) to preserve the structural of the original image and reduce excessive reliance on self-attention maps with ineffective spatial structure (low SIS) to enhance editing performance in TIE tasks. Extensive experiments across diverse TIE tasks demonstrate that SSAIM significantly improves both structural fidelity and editing quality.