In the rapidly evolving world of artificial intelligence, video generation has emerged as a frontier of innovation, with models like OpenAI’s Sora pushing the boundaries of what’s possible. However, while Sora represents a significant leap forward, its limited availability has left many creators and researchers eager for a more accessible alternative. Meet with Open-Sora, an open-source project developed by the Colossal-AI team, aiming to democratize advanced video generation techniques and empower content creators worldwide.

What is OpenAI’s Sora?

OpenAI, a renowned U.S.-based AI research organization, has been at the forefront of AI advancements with groundbreaking models like GPT-3 and DALL-E. Their latest creation, Sora, is a text-to-video model capable of generating high-quality videos based on textual descriptions, extending existing videos, and creating videos from still images. Sora represents a significant milestone in AI-generated video, showcasing the potential for transforming various industries, from entertainment to advertising.

sora architecture

The need for an open-source alternative

Despite the excitement surrounding Sora, the model is not yet available to the public, leaving many creators and researchers without access to this powerful technology.

This is where Open-Sora comes in, offering an open-source alternative that replicates Sora’s architecture while reducing training costs and increasing accessibility.

open sora diagram


Democratizing AI-Generated Video Developed by the Colossal-AI team, Open-Sora aims to make advanced video generation techniques accessible to all by providing a user-friendly platform that simplifies the complexities of video production. By embracing open-source principles, Open-Sora encourages innovation, creativity, and collaboration within the AI community, fostering an environment where developers and creators can build upon each other’s work and push the boundaries of what’s possible.

Key features and advancements

Cost reduction and efficiency

One of the most impressive aspects of Open-Sora is its ability to reduce training costs by 46% compared to Sora. This cost reduction is achieved through various optimization techniques, such as sequence parallelism and hybrid parallelism, which result in a 40% performance improvement over the baseline solution. Additionally, Open-Sora can train 30% longer sequences, up to 819K+ patches, while maintaining faster training speeds.

open sora optimizations

Dynamic resolution and model structures

Open-Sora supports dynamic resolution, allowing users to train videos of any resolution without the need for scaling. It also supports multiple model structures, such as adaLN-zero, cross attention, and in-context conditioning (token concat), as well as various video compression methods, including original video, VQVAE (video native model), and SD-VAE (image native model).

Comprehensive training pipeline

Open-Sora 1.0, released in March 2024, includes the full text-to-video model training process, data processing, training specifics, and model checkpoints. The provided checkpoints can produce 2-second, 512×512 resolution videos with only 3 days of training, a remarkable feat considering OpenAI’s Sora required 152 million samples for training.


open sora performance benchmark

Performance benchmark with DiT-XL/2 model on a H800 SXM 8*80GB GPU server

With a sequence length of 600,000, Open-Sora’s approach provides an improvement in performance and cost savings of over 40% compared to the standard solution.

open sora benchmark longer context

Potential applications and impact

The potential applications of AI-generated video are vast, spanning various industries such as movies, animation, games, and advertising. Open-Sora aims to promote the implementation of AI technology in these fields by providing an accessible and cost-effective solution, empowering content creators with more convenient and efficient tools.

As the development of Open-Sora continues, the Colossal-AI team invites the open-source community to contribute to the project, helping to enhance and surpass the capabilities of OpenAI’s Sora. Through collaboration and shared knowledge, Open-Sora has the potential to revolutionize the video generation landscape, making it more accessible, affordable, and reliable for all.


Open-Sora represents a significant step forward in the democratization of AI-generated video. By providing an open-source alternative to OpenAI’s Sora, the Colossal-AI team has not only reduced training costs but also expanded the possibilities for content creators worldwide. As the project continues to grow and evolve, it is poised to transform the way we create and consume video content, ushering in a new era of AI-powered creativity.

The future of AI-generated video is bright, and with projects like Open-Sora leading the way, we can expect to see even more impressive advancements in the years to come. As more creators and researchers gain access to these powerful tools, the potential for innovation and collaboration grows exponentially, promising a future where the boundaries between human creativity and artificial intelligence become increasingly blurred.

Categorized in:

Computer Vision, Deep Learning,

Last Update: 19/03/2024