---

name: fiftyone-find-duplicates description: Find duplicate or near-duplicate images in FiftyOne datasets using brain similarity computation. Use when users want to deduplicate datasets, find similar images, cluster visually similar content, or remove redundant samples. Requires FiftyOne MCP server with @voxel51/brain plugin installed.

Find Duplicates in FiftyOne Datasets

Overview

Find and remove duplicate or near-duplicate images using FiftyOne's brain similarity operators. Uses deep learning embeddings to identify visually similar images.

Use this skill when:

• Removing duplicate images from datasets
• Finding near-duplicate images (similar but not identical)
• Clustering visually similar images
• Cleaning datasets before training

Prerequisites

• FiftyOne MCP server installed and running
• @voxel51/brain plugin installed and enabled
• Dataset with image samples loaded in FiftyOne

Key Directives

ALWAYS follow these rules:

1. Set context first

Copyset_context(dataset_name="my-dataset")

2. Launch FiftyOne App

Brain operators are delegated and require the app:

Copylaunch_app()

Wait 5-10 seconds for initialization.

3. Discover operators dynamically

Copy# List all brain operators
list_operators(builtin_only=False)

# Get schema for specific operator
get_operator_schema(operator_uri="@voxel51/brain/compute_similarity")

4. Compute embeddings before finding duplicates

Copyexecute_operator(
    operator_uri="@voxel51/brain/compute_similarity",
    params={"brain_key": "img_sim", "model": "mobilenet-v2-imagenet-torch"}
)

5. Close app when done

Copyclose_app()

Complete Workflow

Step 1: Setup

Copy# Set context
set_context(dataset_name="my-dataset")

# Launch app (required for brain operators)
launch_app()

Step 2: Verify Brain Plugin

Copy# Check if brain plugin is available
list_plugins(enabled=True)

# If not installed:
download_plugin(
    url_or_repo="voxel51/fiftyone-plugins",
    plugin_names=["@voxel51/brain"]
)
enable_plugin(plugin_name="@voxel51/brain")

Step 3: Discover Brain Operators

Copy# List all available operators
list_operators(builtin_only=False)

# Get schema for compute_similarity
get_operator_schema(operator_uri="@voxel51/brain/compute_similarity")

# Get schema for find_duplicates
get_operator_schema(operator_uri="@voxel51/brain/find_duplicates")

Step 4: Compute Similarity

Copy# Execute operator to compute embeddings
execute_operator(
    operator_uri="@voxel51/brain/compute_similarity",
    params={
        "brain_key": "img_duplicates",
        "model": "mobilenet-v2-imagenet-torch"
    }
)

Step 5: Find Near Duplicates

Copyexecute_operator(
    operator_uri="@voxel51/brain/find_near_duplicates",
    params={
        "similarity_index": "img_duplicates",
        "threshold": 0.3
    }
)

Threshold guidelines (distance-based, lower = more similar):

• 0.1 = Very similar (near-exact duplicates)
• 0.3 = Near duplicates (recommended default)
• 0.5 = Similar images
• 0.7 = Loosely similar

This operator creates two saved views automatically:

• near duplicates: all samples that are near duplicates
• representatives of near duplicates: one representative from each group

Step 6: View Duplicates in App

After finding duplicates, use set_view to display them in the FiftyOne App:

Option A: Filter by near_dup_id field

Copy# Show all samples that have a near_dup_id (all duplicates)
set_view(exists=["near_dup_id"])

Option B: Show specific duplicate group

Copy# Show samples with a specific duplicate group ID
set_view(filters={"near_dup_id": 1})

Option C: Load saved view (if available)

Copy# Load the automatically created saved view
set_view(view_name="near duplicates")

Option D: Clear filter to show all samples

Copyclear_view()

The find_near_duplicates operator adds a near_dup_id field to samples. Samples with the same ID are duplicates of each other.

Step 7: Delete Duplicates

Option A: Use deduplicate operator (keeps one representative per group)

Copyexecute_operator(
    operator_uri="@voxel51/brain/deduplicate_near_duplicates",
    params={}
)

Option B: Manual deletion from App UI

1. Use set_view(exists=["near_dup_id"]) to show duplicates
2. Review samples in the App at http://localhost:5151/
3. Select samples to delete
4. Use the delete action in the App

Step 8: Clean Up

Copyclose_app()

Available Tools

Session View Tools

Brain Operators for Duplicates

Use list_operators() to discover and get_operator_schema() to see parameters:

Common Use Cases

Use Case 1: Remove Exact Duplicates

For accidentally duplicated files (identical bytes):

Copyset_context(dataset_name="my-dataset")
launch_app()

execute_operator(
    operator_uri="@voxel51/brain/find_exact_duplicates",
    params={}
)

execute_operator(
    operator_uri="@voxel51/brain/deduplicate_exact_duplicates",
    params={}
)

close_app()

Use Case 2: Find and Review Near Duplicates

For visually similar but not identical images:

Copyset_context(dataset_name="my-dataset")
launch_app()

# Compute embeddings
execute_operator(
    operator_uri="@voxel51/brain/compute_similarity",
    params={"brain_key": "near_dups", "model": "mobilenet-v2-imagenet-torch"}
)

# Find duplicates
execute_operator(
    operator_uri="@voxel51/brain/find_near_duplicates",
    params={"similarity_index": "near_dups", "threshold": 0.3}
)

# View duplicates in the App
set_view(exists=["near_dup_id"])

# After review, deduplicate
execute_operator(
    operator_uri="@voxel51/brain/deduplicate_near_duplicates",
    params={}
)

# Clear view and close
clear_view()
close_app()

Use Case 3: Sort by Similarity

Find images similar to a specific sample:

Copyset_context(dataset_name="my-dataset")
launch_app()

execute_operator(
    operator_uri="@voxel51/brain/compute_similarity",
    params={"brain_key": "search"}
)

execute_operator(
    operator_uri="@voxel51/brain/sort_by_similarity",
    params={
        "brain_key": "search",
        "query_id": "sample_id_here",
        "k": 20
    }
)

close_app()

Troubleshooting

Error: "No executor available"

• Cause: Delegated operators require the App executor for UI triggers
• Solution: Direct user to App UI to view results and complete deletion manually
• Affected operators: find_near_duplicates, deduplicate_near_duplicates

Error: "Brain key not found"

• Cause: Embeddings not computed
• Solution: Run compute_similarity first with a brain_key

Error: "Operator not found"

• Cause: Brain plugin not installed
• Solution: Install with download_plugin() and enable_plugin()

Error: "Missing dependency" (e.g., torch, tensorflow)

• The MCP server detects missing dependencies automatically
• Response includes missing_package and install_command
• Example response:

  Copy{
    "error_type": "missing_dependency",
    "missing_package": "torch",
    "install_command": "pip install torch"
  }
  

• Offer to run the install command for the user
• After installation, restart MCP server and retry

Similarity computation is slow

• Use faster model: mobilenet-v2-imagenet-torch
• Use GPU if available
• Process large datasets in batches

Best Practices

1. Discover dynamically - Use list_operators() and get_operator_schema() to get current operator names and parameters
2. Start with default threshold (0.3) and adjust as needed
3. Review before deleting - Direct user to App to inspect duplicates
4. Store embeddings - Reuse for multiple operations via brain_key
5. Handle executor errors gracefully - Guide user to App UI when needed

Performance Notes

Embedding computation time:

• 1,000 images: ~1-2 minutes
• 10,000 images: ~10-15 minutes
• 100,000 images: ~1-2 hours

Memory requirements:

• ~2KB per image for embeddings
• ~4-8KB per image for similarity index

Resources

• FiftyOne Brain Documentation
• Brain Plugin Source

License

Copyright 2017-2025, Voxel51, Inc. Apache 2.0 License