Programador Novato

Ahora que hemos configurado el API de Google Visión vamos a Convertir de imágenes a texto con Java y usaremos como IDE a NetBeans siguiendo estos pasos:

Configuramos el proyecto en NetBeans

Creamos un nuevo proyecto de tipo Java whit Maven y hacemos click en siguiente

Colocamos un nombre y click en Finish

Abrimos pom.xml y desde https://cloud.google.com/vision/docs/detect-labels-image-client-libraries#client-libraries-usage-java agregamos e código

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.google.cloud</groupId>
      <artifactId>libraries-bom</artifactId>
      <version>26.1.3</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>
  <dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-vision</artifactId>
  </dependency>
</dependencies>

Agregamos un Java Main Class en Netbeans

Colocamos un nombre y daos click en finish

En la raiz del proyecto de Netbeans descargamos la imagen de esta url https://raw.githubusercontent.com/GoogleCloudPlatform/python-docs-samples/main/vision/snippets/quickstart/resources/wakeupcat.jpg

Importamos las dependencias de Google visión:

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.Feature.Type;
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.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

Agregamos la función detectText

    public static String detectText(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.TEXT_DETECTION).build();
        AnnotateImageRequest request
                = AnnotateImageRequest.newBuilder().addFeatures(feat).setImage(img).build();
        requests.add(request);
        String texto = "";
        // 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 null;
                }

                // For full list of available annotations, see http://g.co/cloud/vision/docs
                texto = res.getTextAnnotationsList().get(0).getDescription();
            }
        }
        return texto;
    }

En el método main llamamos al método detectText y mostramos el texto de la imagen

    public static void main(String[] args) {
        try {
            String texto= detectText("C:\\Users\\eucm2\\OneDrive\\Documentos\\NetBeansProjects\\OCR-JAVA\\wakeupcat.jpg");
            System.out.println(texto);
        } catch (IOException ex) {
            Logger.getLogger(NewMain.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

Corremos el proyecto en la consola se nos muestra el texto de la imagen

Codigo completo para convertir de imágenes a texto con Java

/*
Convertir de imágenes a texto con Java
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package com.mycompany.ocr.java;

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.Feature.Type;
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.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author eucm2
 */
public class NewMain {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        try {
            String texto= detectText("C:\\Users\\eucm2\\OneDrive\\Documentos\\NetBeansProjects\\OCR-JAVA\\wakeupcat.jpg");
            System.out.println(texto);
        } catch (IOException ex) {
            Logger.getLogger(NewMain.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
    
    public static String detectText(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.TEXT_DETECTION).build();
        AnnotateImageRequest request
                = AnnotateImageRequest.newBuilder().addFeatures(feat).setImage(img).build();
        requests.add(request);
        String texto = "";
        // 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 null;
                }

                // For full list of available annotations, see http://g.co/cloud/vision/docs
                texto = res.getTextAnnotationsList().get(0).getDescription();
            }
        }
        return texto;
    }

    
}