Open-Sora: Democratizing Efficient Video Production for All

We design and implement Open-Sora, an initiative dedicated to efficiently producing high-quality video. We hope to make the model, tools and all details accessible to all. By embracing open-source principles, Open-Sora not only democratizes access to advanced video generation techniques, but also offers a streamlined and user-friendly platform that simplifies the complexities of video generation. With Open-Sora, our goal is to foster innovation, creativity, and inclusivity within the field of content creation.

[中文文档] [潞晨云部署视频教程]

📰 News

• [2024.06.17] 🔥 We released Open-Sora 1.2, which includes 3D-VAE, rectified flow, and score condition. The video quality is greatly improved. [checkpoints] [report]
• [2024.04.25] 🤗 We released the Gradio demo for Open-Sora on Hugging Face Spaces.
• [2024.04.25] We released Open-Sora 1.1, which supports 2s~15s, 144p to 720p, any aspect ratio text-to-image, text-to-video, image-to-video, video-to-video, infinite time generation. In addition, a full video processing pipeline is released. [checkpoints] [report]
• [2024.03.18] We released Open-Sora 1.0, a fully open-source project for video generation. Open-Sora 1.0 supports a full pipeline of video data preprocessing, training with acceleration, inference, and more. Our model can produce 2s 512x512 videos with only 3 days training. [checkpoints] [blog] [report]
• [2024.03.04] Open-Sora provides training with 46% cost reduction. [blog]

🎥 Latest Demo

🔥 You can experience Open-Sora on our 🤗 Gradio application on Hugging Face. More samples are available in our Gallery.

OpenSora 1.1 Demo

2s 240×426	2s 240×426

2s 426×240	4s 480×854

16s 320×320	16s 224×448	2s 426×240

OpenSora 1.0 Demo

2s 512×512	2s 512×512	2s 512×512
A serene night scene in a forested area. [...] The video is a time-lapse, capturing the transition from day to night, with the lake and forest serving as a constant backdrop.	A soaring drone footage captures the majestic beauty of a coastal cliff, [...] The water gently laps at the rock base and the greenery that clings to the top of the cliff.	The majestic beauty of a waterfall cascading down a cliff into a serene lake. [...] The camera angle provides a bird's eye view of the waterfall.
A bustling city street at night, filled with the glow of car headlights and the ambient light of streetlights. [...]	The vibrant beauty of a sunflower field. The sunflowers are arranged in neat rows, creating a sense of order and symmetry. [...]	A serene underwater scene featuring a sea turtle swimming through a coral reef. The turtle, with its greenish-brown shell [...]

Videos are downsampled to .gif for display. Click for original videos. Prompts are trimmed for display, see here for full prompts.

🔆 New Features/Updates

• 📍 Open-Sora 1.2 released. Model weights are available here. See our report 1.2 for more details.
• ✅ Support rectified flow scheduling.
• ✅ Trained our 3D-VAE for temporal dimension compression.
• 📍 Open-Sora 1.1 released. Model weights are available here. It is trained on 0s~15s, 144p to 720p, various aspect ratios videos. See our report 1.1 for more discussions.
• 🔧 Data processing pipeline v1.1 is released. An automatic processing pipeline from raw videos to (text, video clip) pairs is provided, including scene cutting \rightarrow filtering(aesthetic, optical flow, OCR, etc.) \rightarrow captioning \rightarrow managing. With this tool, you can easily build your video dataset.
• ✅ Improved ST-DiT architecture includes rope positional encoding, qk norm, longer text length, etc.
• ✅ Support training with any resolution, aspect ratio, and duration (including images).
• ✅ Support image and video conditioning and video editing, and thus support animating images, connecting videos, etc.
• 📍 Open-Sora 1.0 released. Model weights are available here. With only 400K video clips and 200 H800 days (compared with 152M samples in Stable Video Diffusion), we are able to generate 2s 512×512 videos. See our report 1.0 for more discussions.
• ✅ Three-stage training from an image diffusion model to a video diffusion model. We provide the weights for each stage.
• ✅ Support training acceleration including accelerated transformer, faster T5 and VAE, and sequence parallelism. Open-Sora improves 55% training speed when training on 64x512x512 videos. Details locates at acceleration.md.
• 🔧 Data preprocessing pipeline v1.0, including downloading, video cutting, and captioning tools. Our data collection plan can be found at datasets.md.

View more

• ✅ We find VQ-VAE from VideoGPT has a low quality and thus adopt a better VAE from Stability-AI. We also find patching in the time dimension deteriorates the quality. See our report for more discussions.
• ✅ We investigate different architectures including DiT, Latte, and our proposed STDiT. Our STDiT achieves a better trade-off between quality and speed. See our report for more discussions.
• ✅ Support clip and T5 text conditioning.
• ✅ By viewing images as one-frame videos, our project supports training DiT on both images and videos (e.g., ImageNet & UCF101). See commands.md for more instructions.
• ✅ Support inference with official weights from DiT, Latte, and PixArt.
• ✅ Refactor the codebase. See structure.md to learn the project structure and how to use the config files.

TODO list sorted by priority

View more

• Training Video-VAE and adapt our model to new VAE.
• Scaling model parameters and dataset size.
• Incoporate a better scheduler (rectified flow).
• Evaluation pipeline.
• Complete the data processing pipeline (including dense optical flow, aesthetics scores, text-image similarity, etc.). See the dataset for more information
• Support image and video conditioning.
• Support variable aspect ratios, resolutions, durations.

Contents

• Installation
• Model Weights
• Gradio Demo
• Inference
• Data Processing
• Training
• Evaluation
• Contribution
• Citation
• Acknowledgement

Other useful documents and links are listed below.

• Report: report 1.2, report 1.1, report 1.0, acceleration.md
• Repo structure: structure.md
• Config file explanation: config.md
• Useful commands: commands.md
• Data processing pipeline and dataset: datasets.md
• Each data processing tool's README: dataset conventions and management, scene cutting, scoring, caption
• Evaluation: eval
• Gallery: gallery

Installation

Install from Source

For CUDA 12.1, you can install the dependencies with the following commands. Otherwise, please refer to Installation for more instructions on different cuda version, and additional dependency for data preprocessing.

# create a virtual env and activate (conda as an example)
conda create -n opensora python=3.9
conda activate opensora

# install torch, torchvision and xformers
pip install -r requirements/requirements-cu121.txt

# download the repo
git clone https://github.com/hpcaitech/Open-Sora
cd Open-Sora

# the default installation is for inference only
pip install -v . # for development mode, `pip install -v -e .`


(Optional, recommended for fast speed, especially for training) To enable `layernorm_kernel` and `flash_attn`, you need to install `apex` and `flash-attn` with the following commands.

```bash
# install flash attention
# set enable_flash_attn=False in config to disable flash attention
pip install packaging ninja
pip install flash-attn --no-build-isolation

# install apex
# set enable_layernorm_kernel=False in config to disable apex
pip install -v --disable-pip-version-check --no-cache-dir --no-build-isolation --config-settings "--build-option=--cpp_ext" --config-settings "--build-option=--cuda_ext" git+https://github.com/NVIDIA/apex.git

Use Docker

Run the following command to build a docker image from Dockerfile provided.

docker build -t opensora ./docker

Run the following command to start the docker container in interactive mode.

docker run -ti --gpus all -v {MOUNT_DIR}:/data opensora

Model Weights

Open-Sora 1.2 Model Weights

Resolution	Model Size	Data	#iterations	Batch Size	URL
TBD

See our report 1.2 for more infomation.

Open-Sora 1.1 Model Weights

View more

Resolution	Model Size	Data	#iterations	Batch Size	URL
mainly 144p & 240p	700M	10M videos + 2M images	100k	dynamic	🔗
144p to 720p	700M	500K HQ videos + 1M images	4k	dynamic	🔗

See our report 1.1 for more infomation.

⚠️ LIMITATION: This version contains known issues which we are going to fix in the next version (as we save computation resource for the next release). In addition, the video generation may fail for long duration, and high resolution will have noisy results due to this problem.

Open-Sora 1.0 Model Weights

View more

| Resolution | Model Size | Data | #iterations | Batch Size | GPU days (H800) | URL | | ---------- | ---------- | ------ | ----------- | ---------- | --------------- | | 16×512×512 | 700M | 20K HQ | 20k | 2×64 | 35 | 🔗 | | 16×256×256 | 700M | 20K HQ | 24k | 8×64 | 45 | 🔗 | | 16×256×256 | 700M | 366K | 80k | 8×64 | 117 | 🔗 |

Training orders: 16x256x256 \rightarrow 16x256x256 HQ \rightarrow 16x512x512 HQ.

Our model's weight is partially initialized from PixArt-α. The number of parameters is 724M. More information about training can be found in our report. More about the dataset can be found in datasets.md. HQ means high quality.

⚠️ LIMITATION: Our model is trained on a limited budget. The quality and text alignment is relatively poor. The model performs badly, especially on generating human beings and cannot follow detailed instructions. We are working on improving the quality and text alignment.

Gradio Demo

🔥 You can experience Open-Sora on our 🤗 Gradio application on Hugging Face online.

Local Deployment

If you want to deploy gradio locally, we have also provided a Gradio application in this repository, you can use the following the command to start an interactive web application to experience video generation with Open-Sora.

pip install gradio spaces
python gradio/app.py

This will launch a Gradio application on your localhost. If you want to know more about the Gradio applicaiton, you can refer to the Gradio README.

To enable prompt enhancement and other language input (e.g., 中文输入), you need to set the OPENAI_API_KEY in the environment. Check OpenAI's documentation to get your API key.

export OPENAI_API_KEY=YOUR_API_KEY

Getting Started

In the Gradio application, the basic options are as follows:

The easiest way to generate a video is to input a text prompt and click the "Generate video" button (scroll down if you cannot find). The generated video will be displayed in the right panel. Checking the "Enhance prompt with GPT4o" will use GPT-4o to refine the prompt, while "Random Prompt" button will generate a random prompt by GPT-4o for you. Due to the OpenAI's API limit, the prompt refinement result has some randomness.

Then, you can choose the resolution, duration, and aspect ratio of the generated video. Different resolution and video length will affect the video generation speed. On a 80G H100 GPU, the generation speed and peak memory usage is:

	Image	2s	4s	8s	16s
360p	3s, 24G	18s, 27G	31s, 27G	62s, 28G	121s, 33G
480p	2s, 24G	29s, 31G	55s, 30G	108s, 32G	219s, 36G
720p	6s, 27G	68s, 41G	130s, 39G	260s, 45G	547s, 67G

Note that besides text to video, you can also use image to video generation. You can upload an image and then click the "Generate video" button to generate a video with the image as the first frame. Or you can fill in the text prompt and click the "Generate image" button to generate an image with the text prompt, and then click the "Generate video" button to generate a video with the image generated with the same model.

Then you can specify more options, including "Motion Strength", "Aesthetic" and "Camera Motion". If "Enable" not checked or the choice is "none", the information is not passed to the model. Otherwise, the model will generate videos with the specified motion strength, aesthetic score, and camera motion.

For the aesthetic score, we recommend using values higher than 6. For motion strength, a smaller value will lead to a smoother but less dynamic video, while a larger value will lead to a more dynamic but likely more blurry video. Thus, you can try without it and then adjust it according to the generated video. For the camera motion, sometimes the model cannot follow the instruction well, and we are working on improving it.

You can also adjust the "Sampling steps", this is directly related to the generation speed as it is the number of denoising. A number smaller than 30 usually leads to a poor generation results, while a number larger than 100 usually has no significant improvement. The "Seed" is used for reproducibility, you can set it to a fixed number to generate the same video. The "CFG Scale" controls how much the model follows the text prompt, a smaller value will lead to a more random video, while a larger value will lead to a more text-following video (7 is recommended).

For more advanced usage, you can refer to Gradio README.

Inference

Open-Sora 1.2 Command Line Inference

GPT-4o Prompt Refinement

We find that GPT-4o can refine the prompt and improve the quality of the generated video. With this feature, you can also use other language (e.g., Chinese) as the prompt. To enable this feature, you need prepare your openai api key in the environment:

export OPENAI_API_KEY=YOUR_API_KEY

Then you can inference with --llm-refine True to enable the GPT-4o prompt refinement.

Open-Sora 1.1 Command Line Inference

View more

Since Open-Sora 1.1 supports inference with dynamic input size, you can pass the input size as an argument.

# text to video
python scripts/inference.py configs/opensora-v1-1/inference/sample.py --prompt "A beautiful sunset over the city" --num-frames 32 --image-size 480 854

If your installation do not contain apex and flash-attn, you need to disable them in the config file, or via the folowing command.

python scripts/inference.py configs/opensora-v1-1/inference/sample.py --prompt "A beautiful sunset over the city" --num-frames 32 --image-size 480 854 --layernorm-kernel False --flash-attn False

See here for more instructions including text-to-image, image-to-video, video-to-video, and infinite time generation.

Open-Sora 1.0 Command Line Inference

View more

We have also provided an offline inference script. Run the following commands to generate samples, the required model weights will be automatically downloaded. To change sampling prompts, modify the txt file passed to --prompt-path. See here to customize the configuration.

# Sample 16x512x512 (20s/sample, 100 time steps, 24 GB memory)
torchrun --standalone --nproc_per_node 1 scripts/inference.py configs/opensora/inference/16x512x512.py --ckpt-path OpenSora-v1-HQ-16x512x512.pth --prompt-path ./assets/texts/t2v_samples.txt

# Sample 16x256x256 (5s/sample, 100 time steps, 22 GB memory)
torchrun --standalone --nproc_per_node 1 scripts/inference.py configs/opensora/inference/16x256x256.py --ckpt-path OpenSora-v1-HQ-16x256x256.pth --prompt-path ./assets/texts/t2v_samples.txt

# Sample 64x512x512 (40s/sample, 100 time steps)
torchrun --standalone --nproc_per_node 1 scripts/inference.py configs/opensora/inference/64x512x512.py --ckpt-path ./path/to/your/ckpt.pth --prompt-path ./assets/texts/t2v_samples.txt

# Sample 64x512x512 with sequence parallelism (30s/sample, 100 time steps)
# sequence parallelism is enabled automatically when nproc_per_node is larger than 1
torchrun --standalone --nproc_per_node 2 scripts/inference.py configs/opensora/inference/64x512x512.py --ckpt-path ./path/to/your/ckpt.pth --prompt-path ./assets/texts/t2v_samples.txt

The speed is tested on H800 GPUs. For inference with other models, see here for more instructions. To lower the memory usage, set a smaller vae.micro_batch_size in the config (slightly lower sampling speed).

Data Processing

High-quality data is crucial for training good generation models. To this end, we establish a complete pipeline for data processing, which could seamlessly convert raw videos to high-quality video-text pairs. The pipeline is shown below. For detailed information, please refer to data processing. Also check out the datasets we use.

Training

Open-Sora 1.2 Training

Open-Sora 1.1 Training

View more

Once you prepare the data in a csv file, run the following commands to launch training on a single node.

# one node
torchrun --standalone --nproc_per_node 8 scripts/train.py \
    configs/opensora-v1-1/train/stage1.py --data-path YOUR_CSV_PATH --ckpt-path YOUR_PRETRAINED_CKPT
# multiple nodes
colossalai run --nproc_per_node 8 --hostfile hostfile scripts/train.py \
    configs/opensora-v1-1/train/stage1.py --data-path YOUR_CSV_PATH --ckpt-path YOUR_PRETRAINED_CKPT

Open-Sora 1.0 Training

View more

Once you prepare the data in a csv file, run the following commands to launch training on a single node.

# 1 GPU, 16x256x256
torchrun --nnodes=1 --nproc_per_node=1 scripts/train.py configs/opensora/train/16x256x256.py --data-path YOUR_CSV_PATH
# 8 GPUs, 64x512x512
torchrun --nnodes=1 --nproc_per_node=8 scripts/train.py configs/opensora/train/64x512x512.py --data-path YOUR_CSV_PATH --ckpt-path YOUR_PRETRAINED_CKPT

To launch training on multiple nodes, prepare a hostfile according to ColossalAI, and run the following commands.

colossalai run --nproc_per_node 8 --hostfile hostfile scripts/train.py configs/opensora/train/64x512x512.py --data-path YOUR_CSV_PATH --ckpt-path YOUR_PRETRAINED_CKPT

For training other models and advanced usage, see here for more instructions.

Evaluation

VBench

VBench-i2v

See here for more instructions.

Contribution

Thanks goes to these wonderful contributors:

If you wish to contribute to this project, please refer to the Contribution Guideline.

Acknowledgement

Here we only list a few of the projects. For other works and datasets, please refer to our report.

• ColossalAI: A powerful large model parallel acceleration and optimization system.
• DiT: Scalable Diffusion Models with Transformers.
• OpenDiT: An acceleration for DiT training. We adopt valuable acceleration strategies for training progress from OpenDiT.
• PixArt: An open-source DiT-based text-to-image model.
• Latte: An attempt to efficiently train DiT for video.
• StabilityAI VAE: A powerful image VAE model.
• CLIP: A powerful text-image embedding model.
• T5: A powerful text encoder.
• LLaVA: A powerful image captioning model based on Mistral-7B and Yi-34B.
• PLLaVA: A powerful video captioning model.
• MiraData: A large-scale video dataset with long durations and structured caption.

We are grateful for their exceptional work and generous contribution to open source. Special thanks go to the authors of MiraData and Rectified Flow for their valuable advice and help. We wish to express gratitude towards AK for sharing this project on social media and Hugging Face for providing free GPU resources for our online Gradio demo.

Citation

@software{opensora,
  author = {Zangwei Zheng and Xiangyu Peng and Tianji Yang and Chenhui Shen and Shenggui Li and Hongxin Liu and Yukun Zhou and Tianyi Li and Yang You},
  title = {Open-Sora: Democratizing Efficient Video Production for All},
  month = {March},
  year = {2024},
  url = {https://github.com/hpcaitech/Open-Sora}
}

Star History