Google图片搜索:如何构建反向图片搜索网址？

Question

如何通过java编程将图像转换为"某些字符串"以将其作为参数传递给谷歌图像搜索.实际上我做了一些base64转换的图像,但它不同于谷歌在其图像搜索引擎中做的.我做了这样的转换(java 7):

import javax.xml.bind.DatatypeConverter;
...
            Path p = Paths.get("my_photo.JPG");
            try(InputStream in = Files.newInputStream(p); 
                    PrintWriter write = new PrintWriter("base64.txt");
               ) {
                byte [] bytes = new byte[in.available()];
                in.read(bytes);
                String base64 = DatatypeConverter.printBase64Binary(bytes);
                write.println(base64);

            } catch(IOException ex) {
                ex.printStackTrace();
            }

这个简单程序的输出与url中google的字符串不同.我谈到了之后的那个字符串tbs=sbi:AMhZZ...

Answer 1

这是我对图像搜索工作原理的最佳猜测:

URL中的数据不是图像的编码形式.数据是用于模糊匹配的图像指纹.

您应该注意到,当您上传图像进行搜索时,这是一个两步过程.第一步是通过网址上传图片http://images.google.com/searchbyimage/upload.Google服务器会返回指纹.然后将浏览器重定向到具有基于指纹的查询字符串的搜索页面.

除非Google发布用于生成指纹的算法,否则您将无法从应用程序中生成搜索查询字符串.在此之前,您可以让您的应用程序将图像发布到上载URI.您应该能够解析响应并构造查询字符串.

编辑

这些是我上传文件时发送到服务器的键和值.

image_url       =
btnG            = Search
encoded_image   = // the binary image content goes here
image_content   =
filename        =
hl              = en
bih             = 507
biw             = 1920

"bih"和"biw"看起来像尺寸,但不会对上传的文件产生任何影响.

使用此信息需要您自担风险.它是一个无证的api,可以改变和破坏你的应用程序.

Answer 2

Using google's image search.

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;

import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.DefaultHttpClient;

public class HttpFileUpload {
  public static void main(String args[]){
    try {
      HttpClient client = new DefaultHttpClient();
      String url="https://www.google.co.in/searchbyimage/upload";
      String imageFile="c:\\temp\\shirt.jpg";
      HttpPost post = new HttpPost(url);

      MultipartEntity entity = new MultipartEntity();
      entity.addPart("encoded_image", new FileBody(new File(imageFile)));
      entity.addPart("image_url",new StringBody(""));
      entity.addPart("image_content",new StringBody(""));
      entity.addPart("filename",new StringBody(""));
      entity.addPart("h1",new StringBody("en"));
      entity.addPart("bih",new StringBody("179"));
      entity.addPart("biw",new StringBody("1600"));

      post.setEntity(entity);
      HttpResponse response = client.execute(post);
      BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));         

      String line = "";
      while ((line = rd.readLine()) != null) {
        if (line.indexOf("HREF")>0)
      System.out.println(line.substring(8));
      }

    }catch (ClientProtocolException cpx){
      cpx.printStackTrace();
    }catch (IOException ioex){
      ioex.printStackTrace();
    }
 }
}