CogVideoX is Zhipu AI’s open-weight text-to-video model, built with Tsinghua University’s KEG lab and released in August 2024 as a successor to the original CogVideo project. It ships in 2B and 5B parameter variants using a 3D causal VAE for spatial and temporal compression alongside an expert adaptive LayerNorm transformer, and it supports text-to-video, image-to-video, and video continuation from a single frame or prompt. The 5B model generates clips up to 10 seconds long at up to 768p resolution and 16 frames per second, and Zhipu later shipped a CogVideoX-1.5 update in November 2024 with longer, higher-resolution output. Weights are released under Apache 2.0 and hosted on Hugging Face, and Zhipu also serves the models through its own API, so CogVideoX works both as a self-hosted open model and as a hosted service, similar to how Stability AI and Runway position their video generators.