Mirai:自回归视觉生成需要前瞻
Mirai: Autoregressive Visual Generation Needs Foresight
把「未来词元」的监督信号(显式多步未来表征或匹配的双向表征)注入自回归训练,无需改架构、无额外推理开销,可直接套用到 LlamaGen、VAR 类图像生成模型的训练流程中以加速收敛并降低 FID。
原文依据 Mirai can speed up LlamaGen-B's convergence by up to 10xand reduce the generation FID from 5.34 to 4.34
摘要译文
由模型翻译 · 术语统一 · 请对照原文核对关键结论自回归(AR)视觉生成器将图像建模为离散词元序列,并以下一词元似然进行训练。这种严格的因果监督仅用紧邻的下一个词元来优化每一步,削弱了全局一致性并拖慢收敛。我们追问:源自后续词元的训练信号,即前瞻,能否帮助自回归视觉生成?我们沿注入层级、前瞻布局与前瞻来源三个轴开展了一系列受控诊断实验,揭示出一个关键洞见:将前瞻对齐到自回归模型在二维图像网格上的内部表征,可改善因果建模。我们以 Mirai(日语意为「未来」)来形式化这一洞见,它是一个通用框架,在不改变架构、不增加额外推理开销的前提下将未来信息注入自回归训练:Mirai-E 使用来自单向表征多个未来位置的显式前瞻,而 Mirai-I 则利用来自匹配的双向表征的隐式前瞻。大量实验表明,Mirai 显著加速收敛并提升生成质量。例如,在 ImageNet 类别条件图像生成基准上,Mirai 可将 LlamaGen-B 的收敛速度提升至多 10 倍,并将生成弗雷歇初始距离从 5.34 降至 4.34。我们的研究强调,视觉自回归模型需要前瞻。
英文原文摘要 1371 字符
Autoregressive (AR) visual generators model images as sequences of discrete tokens and are trained with next token likelihood. This strict causality supervision optimizes each step only by its immediate next token, which diminishes global coherence and slows convergence. We ask whether foresight, training signals that originate from later tokens, can help AR visual generation. We conduct a series of controlled diagnostics along the injection level, foresight layout, and foresight source axes, unveiling a key insight: aligning foresight to AR models' internal representation on the 2D image grids improves causality modeling.We formulate this insight with Mirai (meaning "future" in Japanese), a general framework that injects future information into AR training with no architecture change and no extra inference overhead: Mirai-E uses explicit foresight from multiple future positions of unidirectional representations, whereas Mirai-I leverages implicit foresight from matched bidirectional representations.Extensive experiments show that Mirai significantly accelerates convergence and improves generation quality. For instance, Mirai can speed up LlamaGen-B's convergence by up to 10xand reduce the generation FID from 5.34 to 4.34 on the ImageNet class-condition image generation benchmark.Our study highlights that visual autoregressive models need foresight.