Obtenir une prédiction pour la classification d'images

Récupère une prédiction pour la classification d'images à l'aide de la méthode predict.

Exemple de code

Java

Avant d'essayer cet exemple, suivez les instructions de configuration pour Java décrites dans le guide de démarrage rapide de Vertex AI à l'aide des bibliothèques clientes. Pour en savoir plus, consultez la documentation de référence de l'API Vertex AI Java.

Pour vous authentifier auprès de Vertex AI, configurez le service Identifiants par défaut de l'application. Pour en savoir plus, consultez Configurer l'authentification pour un environnement de développement local.


import com.google.cloud.aiplatform.util.ValueConverter;
import com.google.cloud.aiplatform.v1.EndpointName;
import com.google.cloud.aiplatform.v1.PredictResponse;
import com.google.cloud.aiplatform.v1.PredictionServiceClient;
import com.google.cloud.aiplatform.v1.PredictionServiceSettings;
import com.google.cloud.aiplatform.v1.schema.predict.instance.ImageClassificationPredictionInstance;
import com.google.cloud.aiplatform.v1.schema.predict.params.ImageClassificationPredictionParams;
import com.google.cloud.aiplatform.v1.schema.predict.prediction.ClassificationPredictionResult;
import com.google.protobuf.Value;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Base64;
import java.util.List;

public class PredictImageClassificationSample {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String project = "YOUR_PROJECT_ID";
    String fileName = "YOUR_IMAGE_FILE_PATH";
    String endpointId = "YOUR_ENDPOINT_ID";
    predictImageClassification(project, fileName, endpointId);
  }

  static void predictImageClassification(String project, String fileName, String endpointId)
      throws IOException {
    PredictionServiceSettings settings =
        PredictionServiceSettings.newBuilder()
            .setEndpoint("us-central1-aiplatform.googleapis.com:443")
            .build();

    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests. After completing all of your requests, call
    // the "close" method on the client to safely clean up any remaining background resources.
    try (PredictionServiceClient predictionServiceClient =
        PredictionServiceClient.create(settings)) {
      String location = "us-central1";
      EndpointName endpointName = EndpointName.of(project, location, endpointId);

      byte[] contents = Base64.getEncoder().encode(Files.readAllBytes(Paths.get(fileName)));
      String content = new String(contents, StandardCharsets.UTF_8);

      ImageClassificationPredictionInstance predictionInstance =
          ImageClassificationPredictionInstance.newBuilder().setContent(content).build();

      List<Value> instances = new ArrayList<>();
      instances.add(ValueConverter.toValue(predictionInstance));

      ImageClassificationPredictionParams predictionParams =
          ImageClassificationPredictionParams.newBuilder()
              .setConfidenceThreshold((float) 0.5)
              .setMaxPredictions(5)
              .build();

      PredictResponse predictResponse =
          predictionServiceClient.predict(
              endpointName, instances, ValueConverter.toValue(predictionParams));
      System.out.println("Predict Image Classification Response");
      System.out.format("\tDeployed Model Id: %s\n", predictResponse.getDeployedModelId());

      System.out.println("Predictions");
      for (Value prediction : predictResponse.getPredictionsList()) {

        ClassificationPredictionResult.Builder resultBuilder =
            ClassificationPredictionResult.newBuilder();
        // Display names and confidences values correspond to
        // IDs in the ID list.
        ClassificationPredictionResult result =
            (ClassificationPredictionResult) ValueConverter.fromValue(resultBuilder, prediction);
        int counter = 0;
        for (Long id : result.getIdsList()) {
          System.out.printf("Label ID: %d\n", id);
          System.out.printf("Label: %s\n", result.getDisplayNames(counter));
          System.out.printf("Confidence: %.4f\n", result.getConfidences(counter));
          counter++;
        }
      }
    }
  }
}

Node.js

Avant d'essayer cet exemple, suivez les instructions de configuration pour Node.js décrites dans le guide de démarrage rapide de Vertex AI à l'aide des bibliothèques clientes. Pour en savoir plus, consultez la documentation de référence de l'API Vertex AI Node.js.

/**
 * TODO(developer): Uncomment these variables before running the sample.\
 * (Not necessary if passing values as arguments)
 */

// const filename = "YOUR_PREDICTION_FILE_NAME";
// const endpointId = "YOUR_ENDPOINT_ID";
// const project = 'YOUR_PROJECT_ID';
// const location = 'YOUR_PROJECT_LOCATION';
const aiplatform = require('@google-cloud/aiplatform');
const {instance, params, prediction} =
  aiplatform.protos.google.cloud.aiplatform.v1.schema.predict;

// Imports the Google Cloud Prediction Service Client library
const {PredictionServiceClient} = aiplatform.v1;

// Specifies the location of the api endpoint
const clientOptions = {
  apiEndpoint: 'us-central1-aiplatform.googleapis.com',
};

// Instantiates a client
const predictionServiceClient = new PredictionServiceClient(clientOptions);

async function predictImageClassification() {
  // Configure the endpoint resource
  const endpoint = `projects/${project}/locations/${location}/endpoints/${endpointId}`;

  const parametersObj = new params.ImageClassificationPredictionParams({
    confidenceThreshold: 0.5,
    maxPredictions: 5,
  });
  const parameters = parametersObj.toValue();

  const fs = require('fs');
  const image = fs.readFileSync(filename, 'base64');
  const instanceObj = new instance.ImageClassificationPredictionInstance({
    content: image,
  });
  const instanceValue = instanceObj.toValue();

  const instances = [instanceValue];
  const request = {
    endpoint,
    instances,
    parameters,
  };

  // Predict request
  const [response] = await predictionServiceClient.predict(request);

  console.log('Predict image classification response');
  console.log(`\tDeployed model id : ${response.deployedModelId}`);
  const predictions = response.predictions;
  console.log('\tPredictions :');
  for (const predictionValue of predictions) {
    const predictionResultObj =
      prediction.ClassificationPredictionResult.fromValue(predictionValue);
    for (const [i, label] of predictionResultObj.displayNames.entries()) {
      console.log(`\tDisplay name: ${label}`);
      console.log(`\tConfidences: ${predictionResultObj.confidences[i]}`);
      console.log(`\tIDs: ${predictionResultObj.ids[i]}\n\n`);
    }
  }
}
predictImageClassification();

Python

Avant d'essayer cet exemple, suivez les instructions de configuration pour Python décrites dans le guide de démarrage rapide de Vertex AI à l'aide des bibliothèques clientes. Pour en savoir plus, consultez la documentation de référence de l'API Vertex AI Python.

import base64

from google.cloud import aiplatform
from google.cloud.aiplatform.gapic.schema import predict


def predict_image_classification_sample(
    project: str,
    endpoint_id: str,
    filename: str,
    location: str = "us-central1",
    api_endpoint: str = "us-central1-aiplatform.googleapis.com",
):
    # The AI Platform services require regional API endpoints.
    client_options = {"api_endpoint": api_endpoint}
    # Initialize client that will be used to create and send requests.
    # This client only needs to be created once, and can be reused for multiple requests.
    client = aiplatform.gapic.PredictionServiceClient(client_options=client_options)
    with open(filename, "rb") as f:
        file_content = f.read()

    # The format of each instance should conform to the deployed model's prediction input schema.
    encoded_content = base64.b64encode(file_content).decode("utf-8")
    instance = predict.instance.ImageClassificationPredictionInstance(
        content=encoded_content,
    ).to_value()
    instances = [instance]
    # See gs://google-cloud-aiplatform/schema/predict/params/image_classification_1.0.0.yaml for the format of the parameters.
    parameters = predict.params.ImageClassificationPredictionParams(
        confidence_threshold=0.5,
        max_predictions=5,
    ).to_value()
    endpoint = client.endpoint_path(
        project=project, location=location, endpoint=endpoint_id
    )
    response = client.predict(
        endpoint=endpoint, instances=instances, parameters=parameters
    )
    print("response")
    print(" deployed_model_id:", response.deployed_model_id)
    # See gs://google-cloud-aiplatform/schema/predict/prediction/image_classification_1.0.0.yaml for the format of the predictions.
    predictions = response.predictions
    for prediction in predictions:
        print(" prediction:", dict(prediction))

Étapes suivantes

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