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Semantic Search

Semantic Search in Frigate allows you to find tracked objects within your review items using either the image itself, a user-defined text description, or an automatically generated one. This feature works by creating embeddings — numerical vector representations — for both the images and text descriptions of your tracked objects. By comparing these embeddings, Frigate assesses their similarities to deliver relevant search results.

Frigate uses models from Jina AI to create and save embeddings to Frigate's database. All of this runs locally.

Semantic Search is accessed via the Explore view in the Frigate UI.

Minimum System Requirements​

Semantic Search works by running a large AI model locally on your system. Small or underpowered systems like a Raspberry Pi will not run Semantic Search reliably or at all.

A minimum of 8GB of RAM is required to use Semantic Search. A GPU is not strictly required but will provide a significant performance increase over CPU-only systems.

For best performance, 16GB or more of RAM and a dedicated GPU are recommended.

Configuration​

Semantic Search is disabled by default, and must be enabled in your config file or in the UI's Enrichments Settings page before it can be used. Semantic Search is a global configuration setting.

semantic_search:
  enabled: True
  reindex: False
tip

The embeddings database can be re-indexed from the existing tracked objects in your database by pressing the "Reindex" button in the Enrichments Settings in the UI or by adding reindex: True to your semantic_search configuration and restarting Frigate. Depending on the number of tracked objects you have, it can take a long while to complete and may max out your CPU while indexing.

If you are enabling Semantic Search for the first time, be advised that Frigate does not automatically index older tracked objects. You will need to reindex as described above.

Jina AI CLIP (version 1)​

The V1 model from Jina has a vision model which is able to embed both images and text into the same vector space, which allows image -> image and text -> image similarity searches. Frigate uses this model on tracked objects to encode the thumbnail image and store it in the database. When searching for tracked objects via text in the search box, Frigate will perform a text -> image similarity search against this embedding. When clicking "Find Similar" in the tracked object detail pane, Frigate will perform an image -> image similarity search to retrieve the closest matching thumbnails.

The V1 text model is used to embed tracked object descriptions and perform searches against them. Descriptions can be created, viewed, and modified on the Explore page when clicking on thumbnail of a tracked object. See the object description docs for more information on how to automatically generate tracked object descriptions.

Differently weighted versions of the Jina models are available and can be selected by setting the model_size config option as small or large:

semantic_search:
  enabled: True
  model: "jinav1"
  model_size: small
  • Configuring the large model employs the full Jina model and will automatically run on the GPU if applicable.
  • Configuring the small model employs a quantized version of the Jina model that uses less RAM and runs on CPU with a very negligible difference in embedding quality.

Jina AI CLIP (version 2)​

Frigate also supports the V2 model from Jina, which introduces multilingual support (89 languages). In contrast, the V1 model only supports English.

V2 offers only a 3% performance improvement over V1 in both text-image and text-text retrieval tasks, an upgrade that is unlikely to yield noticeable real-world benefits. Additionally, V2 has significantly higher RAM and GPU requirements, leading to increased inference time and memory usage. If you plan to use V2, ensure your system has ample RAM and a discrete GPU. CPU inference (with the small model) using V2 is not recommended.

To use the V2 model, update the model parameter in your config:

semantic_search:
  enabled: True
  model: "jinav2"
  model_size: large

For most users, especially native English speakers, the V1 model remains the recommended choice.

note

Switching between V1 and V2 requires reindexing your embeddings. The embeddings from V1 and V2 are incompatible, and failing to reindex will result in incorrect search results.

GPU Acceleration​

The CLIP models are downloaded in ONNX format, and the large model can be accelerated using GPU / NPU hardware, when available. This depends on the Docker build that is used. You can also target a specific device in a multi-GPU installation.

semantic_search:
  enabled: True
  model_size: large
  # Optional, if using the 'large' model in a multi-GPU installation
  device: 0
info

If the correct build is used for your GPU / NPU and the large model is configured, then the GPU / NPU will be detected and used automatically. Specify the device option to target a specific GPU in a multi-GPU system (see onnxruntime's provider options). If you do not specify a device, the first available GPU will be used.

See the Hardware Accelerated Enrichments documentation.

Usage and Best Practices​

  1. Semantic Search is used in conjunction with the other filters available on the Explore page. Use a combination of traditional filtering and Semantic Search for the best results.
  2. Use the thumbnail search type when searching for particular objects in the scene. Use the description search type when attempting to discern the intent of your object.
  3. Because of how the AI models Frigate uses have been trained, the comparison between text and image embedding distances generally means that with multi-modal (thumbnail and description) searches, results matching description will appear first, even if a thumbnail embedding may be a better match. Play with the "Search Type" setting to help find what you are looking for. Note that if you are generating descriptions for specific objects or zones only, this may cause search results to prioritize the objects with descriptions even if the the ones without them are more relevant.
  4. Make your search language and tone closely match exactly what you're looking for. If you are using thumbnail search, phrase your query as an image caption. Searching for "red car" may not work as well as "red sedan driving down a residential street on a sunny day".
  5. Semantic search on thumbnails tends to return better results when matching large subjects that take up most of the frame. Small things like "cat" tend to not work well.
  6. Experiment! Find a tracked object you want to test and start typing keywords and phrases to see what works for you.

Triggers​

Triggers utilize Semantic Search to automate actions when a tracked object matches a specified image or description. Triggers can be configured so that Frigate executes a specific actions when a tracked object's image or description matches a predefined image or text, based on a similarity threshold. Triggers are managed per camera and can be configured via the Frigate UI in the Settings page under the Triggers tab.

note

Semantic Search must be enabled to use Triggers.

Configuration​

Triggers are defined within the semantic_search configuration for each camera in your Frigate configuration file or through the UI. Each trigger consists of a friendly_name, a type (either thumbnail or description), a data field (the reference image event ID or text), a threshold for similarity matching, and a list of actions to perform when the trigger fires.

Triggers are best configured through the Frigate UI.

Managing Triggers in the UI​

  1. Navigate to the Settings page and select the Triggers tab.
  2. Choose a camera from the dropdown menu to view or manage its triggers.
  3. Click Add Trigger to create a new trigger or use the pencil icon to edit an existing one.
  4. In the Create Trigger dialog:
    • Enter a Name for the trigger (e.g., "red_car_alert").
    • Enter a descriptive Friendly Name for the trigger (e.g., "Red car on the driveway camera").
    • Select the Type (Thumbnail or Description).
    • For Thumbnail, select an image to trigger this action when a similar thumbnail image is detected, based on the threshold.
    • For Description, enter text to trigger this action when a similar tracked object description is detected.
    • Set the Threshold for similarity matching.
    • Select Actions to perform when the trigger fires.
  5. Save the trigger to update the configuration and store the embedding in the database.

When a trigger fires, the UI highlights the trigger with a blue outline for 3 seconds for easy identification.

Usage and Best Practices​

  1. Thumbnail Triggers: Select a representative image (event ID) from the Explore page that closely matches the object you want to detect. For best results, choose images where the object is prominent and fills most of the frame.
  2. Description Triggers: Write concise, specific text descriptions (e.g., "Person in a red jacket") that align with the tracked object’s description. Avoid vague terms to improve matching accuracy.
  3. Threshold Tuning: Adjust the threshold to balance sensitivity and specificity. A higher threshold (e.g., 0.8) requires closer matches, reducing false positives but potentially missing similar objects. A lower threshold (e.g., 0.6) is more inclusive but may trigger more often.
  4. Using Explore: Use the context menu or right-click / long-press on a tracked object in the Grid View in Explore to quickly add a trigger based on the tracked object's thumbnail.
  5. Editing triggers: For the best experience, triggers should be edited via the UI. However, Frigate will ensure triggers edited in the config will be synced with triggers created and edited in the UI.

Notes​

  • Triggers rely on the same Jina AI CLIP models (V1 or V2) used for semantic search. Ensure semantic_search is enabled and properly configured.
  • Reindexing embeddings (via the UI or reindex: True) does not affect trigger configurations but may update the embeddings used for matching.
  • For optimal performance, use a system with sufficient RAM (8GB minimum, 16GB recommended) and a GPU for large model configurations, as described in the Semantic Search requirements.

FAQ​

Why can't I create a trigger on thumbnails for some text, like "person with a blue shirt" and have it trigger when a person with a blue shirt is detected?​

TL;DR: Text-to-image triggers aren’t supported because CLIP can confuse similar images and give inconsistent scores, making automation unreliable. The same word–image pair can give different scores and the score ranges can be too close together to set a clear cutoff.

Text-to-image triggers are not supported due to fundamental limitations of CLIP-based similarity search. While CLIP works well for exploratory, manual queries, it is unreliable for automated triggers based on a threshold. Issues include embedding drift (the same text–image pair can yield different cosine distances over time), lack of true semantic grounding (visually similar but incorrect matches), and unstable thresholding (distance distributions are dataset-dependent and often too tightly clustered to separate relevant from irrelevant results). Instead, it is recommended to set up a workflow with thumbnail triggers: first use text search to manually select 3–5 representative reference tracked objects, then configure thumbnail triggers based on that visual similarity. This provides robust automation without the semantic ambiguity of text to image matching.