Detect logos in a local image file.

Perform logo detection on a locally stored image file.

Explore further

For detailed documentation that includes this code sample, see the following:

Code sample

Go

To learn how to install and use the client library for Vision API Product Search, see Vision API Product Search client libraries. For more information, see the Vision API Product Search Go API reference documentation.

To authenticate to Vision API Product Search, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 


// detectLogos gets logos from the Vision API for an image at the given file path.
func detectLogos(w io.Writer, file string) error {
	ctx := context.Background()

	client, err := vision.NewImageAnnotatorClient(ctx)
	if err != nil {
		return err
	}

	fileBytes, err := os.ReadFile(file)
	if err != nil {
		return err
	}

	image := &visionpb.Image{
		Content: fileBytes,
	}

	feature := &visionpb.Feature{
		Type:       visionpb.Feature_LOGO_DETECTION,
		MaxResults: 10,
	}

	request := &visionpb.BatchAnnotateImagesRequest{
		Requests: []*visionpb.AnnotateImageRequest{
			{
				Image:    image,
				Features: []*visionpb.Feature{feature},
			},
		},
	}

	response, err := client.BatchAnnotateImages(ctx, request)
	if err != nil {
		return err
	}

	for _, resp := range response.Responses {
		if resp.Error != nil {
			fmt.Fprintf(w, "Error: %v\n", resp.Error)
			continue
		}
		if len(resp.LogoAnnotations) == 0 {
			fmt.Fprintln(w, "No logos found.")
		} else {
			fmt.Fprintln(w, "Logos:")
			for _, annotation := range resp.LogoAnnotations {
				fmt.Fprintln(w, annotation.Description)
			}
		}
	}

	return nil
}

Java

To learn how to install and use the client library for Vision API Product Search, see Vision API Product Search client libraries. For more information, see the Vision API Product Search Java API reference documentation.

To authenticate to Vision API Product Search, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 


import com.google.cloud.vision.v1.AnnotateImageRequest;
import com.google.cloud.vision.v1.AnnotateImageResponse;
import com.google.cloud.vision.v1.BatchAnnotateImagesResponse;
import com.google.cloud.vision.v1.EntityAnnotation;
import com.google.cloud.vision.v1.Feature;
import com.google.cloud.vision.v1.Image;
import com.google.cloud.vision.v1.ImageAnnotatorClient;
import com.google.protobuf.ByteString;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class DetectLogos {
  public static void detectLogos() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String filePath = "path/to/your/image/file.jpg";
    detectLogos(filePath);
  }

  // Detects logos in the specified local image.

  public static void detectLogos(String filePath) throws IOException {
    List<AnnotateImageRequest> requests = new ArrayList<>();

    ByteString imgBytes = ByteString.readFrom(new FileInputStream(filePath));

    Image img = Image.newBuilder().setContent(imgBytes).build();
    Feature feat = Feature.newBuilder().setType(Feature.Type.LOGO_DETECTION).build();
    AnnotateImageRequest request =
        AnnotateImageRequest.newBuilder().addFeatures(feat).setImage(img).build();
    requests.add(request);

    // 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 (ImageAnnotatorClient client = ImageAnnotatorClient.create()) {
      BatchAnnotateImagesResponse response = client.batchAnnotateImages(requests);
      List<AnnotateImageResponse> responses = response.getResponsesList();

      for (AnnotateImageResponse res : responses) {
        if (res.hasError()) {
          System.out.format("Error: %s%n", res.getError().getMessage());
          return;
        }

        // For full list of available annotations, see http://g.co/cloud/vision/docs
        for (EntityAnnotation annotation : res.getLogoAnnotationsList()) {
          System.out.println(annotation.getDescription());
        }
      }
    }
  }
}

Node.js

To learn how to install and use the client library for Vision API Product Search, see Vision API Product Search client libraries. For more information, see the Vision API Product Search Node.js API reference documentation.

To authenticate to Vision API Product Search, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

const vision = require('@google-cloud/vision');
const fs = require('fs');

// Creates a client
const client = new vision.ImageAnnotatorClient();

/**
 * TODO(developer): Uncomment the following line before running the sample.
 */
// const fileName = 'Local image file, e.g. /path/to/image.png';

const imageBuffer = fs.readFileSync(fileName);
const base64Image = imageBuffer.toString('base64');

const request = {
  requests: [
    {
      image: {
        content: base64Image,
      },
      features: [
        {
          type: 'LOGO_DETECTION',
        },
      ],
    },
  ],
};

// Performs logo detection on the local file
const [response] = await client.batchAnnotateImages(request);

response.responses.forEach(res => {
  if (res.logoAnnotations) {
    console.log('Logos:');
    res.logoAnnotations.forEach(logo => console.log(logo));
  }

  if (res.error) {
    console.error(` - Error: ${res.error.message}`);
  }
});

PHP

To learn how to install and use the client library for Vision API Product Search, see Vision API Product Search client libraries.

To authenticate to Vision API Product Search, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

namespace Google\Cloud\Samples\Vision;

use Google\Cloud\Vision\V1\Client\ImageAnnotatorClient;

/**
 * @param string $path Path to the image, e.g. "path/to/your/image.jpg"
 */
function detect_logo(string $path)
{
    $imageAnnotator = new ImageAnnotatorClient();

    # annotate the image
    $image = file_get_contents($path);
    $response = $imageAnnotator->logoDetection($image);
    $logos = $response->getLogoAnnotations();

    printf('%d logos found:' . PHP_EOL, count($logos));
    foreach ($logos as $logo) {
        print($logo->getDescription() . PHP_EOL);
    }

    $imageAnnotator->close();
}

Python

To learn how to install and use the client library for Vision API Product Search, see Vision API Product Search client libraries. For more information, see the Vision API Product Search Python API reference documentation.

To authenticate to Vision API Product Search, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

def detect_logos(path):
    """Detects logos in the file."""
    from google.cloud import vision

    client = vision.ImageAnnotatorClient()

    with open(path, "rb") as image_file:
        content = image_file.read()

    image = vision.Image(content=content)

    request = {
        "image": image,
        "features": [{"type_": vision.Feature.Type.LOGO_DETECTION}],
    }

    response = client.annotate_image(request=request)
    logos = response.logo_annotations
    print("Logos:")

    for logo in logos:
        print(logo.description)

    if response.error.message:
        raise Exception(
            "{}\nFor more info on error messages, check: "
            "https://cloud.google.com/apis/design/errors".format(response.error.message)
        )

What's next

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