java - 如何使用 JAVA 将本地镜像而不是 URL 发送到 Microsoft 计算机视觉 API

Question

问题是如何加载图像文件并将其作为对象传递给 Microsoft Computer Vision API，Microsoft 网站中的所有示例代码都是从 url 读取图像。

// This sample uses the Apache HTTP client library(org.apache.httpcomponents:httpclient:4.2.4)
// and the org.json library (org.json:json:20170516).
package com.mparnisari.test;

import java.awt.image.BufferedImage;
import java.io.File;
import java.net.URI;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

import javax.imageio.ImageIO;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.FileEntity;
import org.apache.http.entity.StringEntity;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.json.JSONObject;


public class Main
{    
    public static final String subscriptionKey = "MY-KEY-HERE";

    public static final String uriBase = 
        "https://westcentralus.api.cognitive.microsoft.com/vision/v1.0/analyze";

    public static void main(String[] args)
    {
        HttpClient httpclient = new DefaultHttpClient();

        try
        {
            URIBuilder builder = new URIBuilder(uriBase);

            builder.setParameter("visualFeatures", "Categories,Description,Color");
            builder.setParameter("language", "en");

            URI uri = builder.build();
            HttpPost request = new HttpPost(uri);

            request.setHeader("Content-Type", "application/json");
            request.setHeader("Ocp-Apim-Subscription-Key", subscriptionKey);

            // Request body.
            BufferedImage image = null;
            File f = null;
            f = new File("C:\\Coffee.jpg"); //image file path
            image = ImageIO.read(f);

            File file = new File("C:\\Coffee.jpg");

            FileEntity reqEntityF = 
                new FileEntity(file, ContentType.APPLICATION_OCTET_STREAM);

            request.setEntity(reqEntityF);

            HttpResponse response = httpclient.execute(request);
            HttpEntity entity = response.getEntity();

            if (entity != null)
            {
                // Format and display the JSON response.
                String jsonString = EntityUtils.toString(entity);
                JSONObject json = new JSONObject(jsonString);
                System.out.println("REST Response:\n");
                System.out.println(json.toString(2));
            }
        }
        catch (Exception e)
        {
            System.out.println(e.getMessage());
        }
    }
}

输出为:

REST Response:

{
  "code": "BadArgument",
  "requestId": "7ecf2198-1b7f-44d0-9cc2-e05e28791281",
  "message": "JSON format error."
}

如 stackoverflow 指南中的其他帖子所述，使用 FileEntity 上传图像。但它不起作用。

我认为这部分应该以某种方式重构以读取图像而不是 URL。

// Execute the REST API call and get the response entity.
HttpResponse response = httpclient.execute(request);
HttpEntity entity = response.getEntity();

让我知道解决此问题的最佳解决方案是什么，因为如果可以将图像从本地传递到 API，那么使用 for 循环来分析图像集会很棒。

Answer 1

正如@Jon所说，您需要更改content-type header 。

// Request headers.
request.setHeader("Content-Type", "application/octet-stream");

// Request body.
File file = new File(imagePath);
FileEntity reqEntity = new FileEntity(file);
request.setEntity(reqEntity);