  Generative AI models have shown impressive ability to produce images with
text prompts, which could benefit creativity in visual art creation and
self-expression. However, it is unclear how precisely the generated images
express contexts and emotions from the input texts. We explored the emotional
expressiveness of AI-generated images and developed RePrompt, an automatic
method to refine text prompts toward precise expression of the generated
images. Inspired by crowdsourced editing strategies, we curated intuitive text
features, such as the number and concreteness of nouns, and trained a proxy
model to analyze the feature effects on the AI-generated image. With model
explanations of the proxy model, we curated a rubric to adjust text prompts to
optimize image generation for precise emotion expression. We conducted
simulation and user studies, which showed that RePrompt significantly improves
the emotional expressiveness of AI-generated images, especially for negative
emotions.
