Conditional diffusion models have exhibited superior performance in high-fidelity text-guided visual generation and editing. Nevertheless, prevailing text-guided visual diffusion models primarily focus on incorporating text-visual relationships exclusively into the reverse process, often disregarding their relevance in the forward process. This inconsistency between forward and reverse processes may limit the precise conveyance of textual semantics in visual synthesis results. To address this issue, we propose a novel and general contextualized diffusion model (ContextDiff) by incorporating the cross-modal context encompassing interactions and alignments between text condition and visual sample into forward and reverse processes. We propagate this context to all timesteps in the two processes to adapt their trajectories, thereby facilitating cross-modal conditional modeling. We generalize our contextualized diffusion to both DDPMs and DDIMs with theoretical derivations, and demonstrate the effectiveness of our model in evaluations with two challenging tasks: text-to-image generation, and text-to-video editing. In each task, our ContextDiff achieves new state-of-the-art performance, significantly enhancing the semantic alignment between text condition and generated samples, as evidenced by quantitative and qualitative evaluations. Our code is available at https://github.com/YangLing0818/ContextDiff

我们提出了一种新颖而通用的上下文扩散模型(ContextDiff)，通过将文本条件与视觉样本之间的交互和对齐引入前向和后向过程中，将上下文传播到这两个过程的所有时间步，从而促进跨模态条件建模，在文本到图像生成和文本到视频编辑的两个挑战性任务中，我们的ContextDiff实现了新的最先进性能，通过定量和定性评估明显增强了文本条件与生成样本之间的语义对齐。

跨模态语境扩散模型的文本导向视觉生成与编辑