FlowCred:用于联合文本到视频后训练的分层信用分配与功能协调
FlowCred: Hierarchical Credit Assignment and Functional Coordination for Joint Text-to-Video Post-Training
AI总结:
FlowCred是用于联合文本到视频后训练的两级框架,通过分层信用分配与功能协调解决联合训练的歧义,在多个T2V基准上提升性能且不增加预算,效果获多维度验证。
摘要:
提示优化和生成器后训练是改进文本到视频(T2V)生成的两种互补方式,近期系统越来越多地联合训练这两个模块。但从同一终端奖励优化提示策略和视频生成器会产生两个歧义:提示质量与随机生成相混淆,且两个模块可能实现重叠的局部改进。我们提出FlowCred,一种用于联合T2V后训练的两级框架。首先,分层信用分配使用匹配的提示-种子展开网格,在共享随机性下分离提示级信用与提示条件生成器残差。其次,功能协调在实际生成轨迹的状态下探测替代当前策略提示,为提示优化提供生成器感知证据,同时选择性衰减已被条件变化支持的生成器更新。在多个T2V基准上,FlowCred始终改进匹配的联合训练基线。在LTX-2.5上,FlowCred将严格匹配的联合训练对照在T2V-CompBench上的表现从61.47提升至64.46,在StoryEval上从55.58提升至58.08,且未增加解码视频或奖励模型调用预算。因子分析和已实现更新分析显示提示塑造与生成器路由的互补贡献,人工评估及跨骨干、更新器族的迁移提供进一步支持证据。
英文摘要:
Prompt optimization and generator post-training are two complementary ways to improve text-to-video (T2V) generation, and recent systems increasingly train both modules jointly. However, optimizing a prompt policy and a video generator from the same terminal reward creates two ambiguities: prompt quality is confounded with stochastic generation, and the two modules may realize overlapping local improvements. We introduce FlowCred, a two-level framework for joint T2V post-training. First, hierarchical credit assignment uses matched prompt-seed rollout grids to separate prompt-level credit from prompt-conditioned generator residuals under shared randomness. Second, functional coordination probes alternative current-policy prompts at states from actual generation trajectories, providing generator-aware evidence for prompt optimization while selectively attenuating generator updates already supported by conditioning changes. Across multiple T2V benchmarks, FlowCred consistently improves matched joint-training baselines. On LTX-2.5, FlowCred improves a strictly matched joint-training control from 61.47 to 64.46 on T2V-CompBench and from 55.58 to 58.08 on StoryEval, without increasing decoded-video or reward-model-call budgets. Factorial and realized-update analyses show complementary contributions from prompt shaping and generator routing, while human evaluation and transfer across backbones and updater families provide further supporting evidence.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。