# EmoReward: Self-Evolving Reward Calibration for Emotional Video Generation RL > Source: > Published: 2026-11-05 07:00:52+00:00 Group Relative Policy Optimization (GRPO) has advanced generative model post-training in verifiable domains such as code and mathematics, but evaluating video quality, especially emotional expression, often depends on subjective aesthetics and has no uniquely correct target. Existing approaches typi