Reproducible low-level artifacts found in ChatGPT image generation

DickHorner · reddit · 2026-08-17

A user discovered reproducible, canvas-aligned texture artifacts while testing ChatGPT's image generation and iterative editing features.

Phenomenon:

Faint cloudy/mottled textures appear in smooth areas (backgrounds, skin) after multiple rounds of generative editing.
Repeated edits reinforce the texture, while some areas (faces) appear protected/stable.

Key Experiments:

Image Shifting: Shifting the image by 20px before altering changed the artifact intensity, suggesting it's tied to canvas coordinates, not random noise.
Black Image Test: Multiple independently generated "black" images showed significant correlation in non-zero pixels (correlation 0.848, Jaccard overlap 0.766), much higher than expected for random independent pixels.

This suggests an underlying spatial pattern or processing mechanism within the model causing non-random artifacts.

More from Multimodal