predictor.classify_image failed with error "Invalid iteration"

Samike 21 Reputation points

I've created and trained an image classification model using Azure Custom Vision (Cognitive Services) and published the model with API. Now, I've written a simple code in Python which takes an image from my local file and calls the API. However, I'm still getting this error even though the Iteration surely exists: Invalid iteration

My code:

PROJECT_ID = "my project id"
prediction_key = "my prediction key"

prediction_credentials = ApiKeyCredentials(in_headers={"Prediction-key": prediction_key})
predictor = CustomVisionPredictionClient(ENDPOINT, prediction_credentials)

image_location = "/tmp/123.jpg"
publish_iteration_name = "Iteration2"

with open(image_location, "rb") as image_contents:
    results = predictor.classify_image(
        PROJECT_ID, publish_iteration_name,
Azure Cognitive Services
Azure Cognitive Services
A group of Azure artificial intelligence services and cognitive APIs that help build intelligent apps.
1,154 questions
Azure Custom Vision
Azure Custom Vision
An Azure artificial intelligence service and end-to-end platform for applying computer vision to specific domains.
142 questions
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Accepted answer
  1. GiftA-MSFT 11,111 Reputation points

    The classificationType shows null, meaning that you created an object detection model. Please follow this example instead to test your model. It should be predictor.detect_image() instead of predictor.classify_image(). Hope this helps!

    # Open the sample image and get back the prediction results.  
    with open(base_image_location + "images/Test/test_od_image.jpg", mode="rb") as test_data:  
        results = predictor.detect_image(, publish_iteration_name, test_data)  
    1 person found this answer helpful.

1 additional answer

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  1. GiftA-MSFT 11,111 Reputation points

    Hi, the error has to do with the publish name. Ensure that you are entering a valid publish name that you specified when publishing the model. You can retrieve the publish name using the GetIterations API. If you're following this example, the publish name would be publish_iteration_name = "classifyModel". Hope this helps.