Serialize a Model

For larger models, it is advisable to use a serialized asset, which typically comes with the file extension .sentis.

Create a Serialized Asset

Once you've imported the ONNX file into your asset folder, you can click on it. In the Inspector window, click Serialize to StreamingAssets. This will create a serialized version of your model and save it in the StreamingAssets folder.

Loading a Serialized Asset

The code to load a serialized model is much the same. For example, if your model is called mymodel.sentis, the corresponding code is:

Model model = ModelLoader.Load(Application.streamingAssetsPath + "/mymodel.sentis");

Advantages of using Serialized Models

Some advantages of using a serialized model are:

• Saves disk space in your project
• Faster loading times
• Validated to work in Unity
• Easier to share

Serialization layout

A .sentis file is serialized using FlatBuffers as follows

             ┌───────────────────────────────────┐
             │Flatbuffer-serialized              |
             | model desription                  │
             │                                   │
          ┌─ ├───────────────────────────────────┤
          │  │ Weight chunk data                 |
          │  │                                   │
          │  │                                   │
Weights  ─┤  ├───────────────────────────────────┤
          │  │ Weight chunk data                 │
          │  │                                   │
          │  │                                   │
          │  ├───────────────────────────────────┤
          │  │...                                │
          └─ └───────────────────────────────────┘

Refer to Sentis/Runtime/Core/Serialization/program.fbs for more info