Delete target image

EasyAR provides two ways to handle recognition images that are no longer needed: permanent deletion and temporary deactivation. To ensure the stability of the production environment, please carefully read the following instructions.

Through the EasyAR web management center

Steps: Log in to the EasyAR developer center -> Cloud recognition management -> Select the corresponding image library -> Click Manage to enter the image library management interface.
Deletion methods:
- Batch deletion: Check the target images in the list, click Delete, and confirm.
- Single deletion: Click to enter the details page of the target image, then click the Delete button on the page.

Deletion operation guide

Warning

Deletion is irreversible. Once confirmed, all feature data and associated information of the image will be permanently lost. It is recommended to verify the process in a test image library first. Direct destructive testing in the production environment is strictly prohibited.

Best practices: deactivating target images

In most business scenarios, if you are unsure whether an image will be used again in the future, it is recommended to use deactivation instead of deletion.

Features: Deactivated target images remain in the database list but do not participate in the cloud recognition search process. However, they occupy recognition quota.
Deactivation method: Check the recognition images in the management interface and click Deactivate.

Deactivation operation guide

API deactivation: By calling the Update target image API, set the active attribute to 0.

Using the API to delete target images

Automated cleanup of recognition images can be achieved through the REST API.

Preparation

Before starting, read the Delete target image API documentation and prepare the following resources:

CRS AppId
API Key / Secret or Token
Server-end URL (port 443)
TargetId: The unique ID of the target image to be deleted. If the TargetId does not exist, the API will return statusCode: 404 (Target not found).

Please replace the placeholder with actual parameters and run the curl script

Your-Server-side-URL → Actual API Host
Your-Token → Actual API Key Authorization Token
Your-CRS-AppId → Your appId
Your-todo-TargetId → Target ID to be deleted

curl -X DELETE "https://<Your-Server-side-URL>/target/<Your-todo-TargetId>?appId=<Your-CRS-AppId>" \
  -H "Content-Type: application/json" \
  -H "Authorization: <Your-Token>"

Download Java sample code

Java Samples Download

Import project via Maven

Step 1. Open the relevant code file RemoveTarget.java

Step 2. Modify global variables, replacing authentication parameters from your manifest

CRS AppId
API Key / API Secret
TARGET_MGMT_URL → Server-end URL
TARGET_ID → TargetId of the target to be deleted

public class RemoveTarget {

    private static final String TARGET_MGMT_URL = "https://cn1.crs.easyar.com";
    private static final String CRS_APPID       = "--here is your CRS AppId--";
    private static final String API_KEY         = "--here is your API Key--";
    private static final String API_SECRET      = "--here is your API Secret--";
    private static final String TARGET_ID       = "my_targetid";
    /* TO_DEL_IDs lists all the targetIds to be removed
     * must be separated by ","
     */
    private static final String TO_DEL_IDs = "targetId1,targetId2,targetId3";

    public String remove(Auth auth, String targetId) throws IOException {
        okhttp3.Request request = new okhttp3.Request.Builder()
                .url(auth.getCloudURL()+"/target/"+targetId+"?"+ Common.toParam(
                        Auth.signParam(new JSONObject(), auth.getAppId(), auth.getApiKey(), auth.getApiSecret())
                ))
                .delete()
                .build();
        return new OkHttpClient.Builder().build().newCall(request).execute().body().string();
    }

    public String removeMultiTargets(Auth auth, String targetIds) throws IOException {
        JSONObject params = new JSONObject().put("targetId", targetIds);
        Auth.signParam(params, auth.getAppId(), auth.getApiKey(), auth.getApiSecret());
        RequestBody requestBody = FormBody.create(MediaType.parse("application/json; charset=utf-8")
                , params.toString());
        okhttp3.Request request = new okhttp3.Request.Builder()
                .url(auth.getCloudURL() + "/targets")
                .delete(requestBody)
                .build();
        return new OkHttpClient.Builder().build().newCall(request).execute().body().string();
    }
    public static void main(String[] args) throws IOException{
        Auth accessInfo  =  new Auth(CRS_APPID, API_KEY, API_SECRET, TARGET_MGMT_URL);
        System.out.println(new RemoveTarget().remove(accessInfo, TARGET_ID));
        System.out.println(new RemoveTarget().removeMultiTargets(accessInfo, TO_DEL_IDs));
    }
}

Step 3. Run Main

Download NodeJS sample code

NodeJS Samples Download

Step 1. Configure key file keys.json

CRS AppId
API Key / API Secret
to-delete-targetId

{
  "appId": "--here is your appId for CRS App Instance for SDK 4--",
  "apiKey": "--here is your api key which is create from website and which has crs permission--",
  "apiSecret": "--here is your api secret which is create from website--"
}

Step 2. Run, specify the key file and server-end URL

node bin/deleteTarget <to-delete-targetId> -t <Server-end-URL> -c keys.json

var argv = require('yargs')
    .usage('Usage: $0 [targetId] -t [host] -c [keys]')
    .demand(1)
    .default('t', 'http://localhost:8888').alias('t', 'host')
    .default('c', 'keys.json').alias('c', 'keys')
    .help('h').alias('h', 'help')
    .epilog('copyright 2015, sightp.com')
    .argv;

var fs = require('fs');

var targetId = argv._[0];
var host = argv.host;
var keys = JSON.parse(fs.readFileSync(argv.keys));

var farmer = require('../farmer')(host, keys.appKey, keys.appSecret);

farmer.deleteTarget(targetId)
.then(function(resp) {
    console.log(resp.result.targetId);
})
.fail(function(err) {
    console.log(err);
});

The deleteTarget function calls the cloud service interface, sample code is in farmer.js

function deleteTarget(targetId) {
    return Q.promise(function(resolve, reject) {
        request.del(host + '/target/' + targetId)
        .query(signParams())
        .end(done(resolve, reject));
    });
}

Download PHP sample code

PHP Samples Download

Step 1. Open the entry code demo.php

Step 2. Modify global variables, replace the authentication parameters in your preparation list

CRS AppId
API Key / API Secret
Server-end URL
toDeleteTargetId

<?php
include 'EasyARClientSdkCRS.php';
$apiKey = 'API Key';
$apiSecret = 'API Secret';
$crsAppId = 'CRS AppId'
$crsCloudUrl = 'https://cn1-crs.easyar.com';
$toDeleteTargetId = 'to-delete-targetId';

$sdk = new EasyARClientSdkCRS($apiKey, $apiSecret, $crsAppId, $crsCloudUrl);

$rs = $sdk->delete($toDeleteTargetId);
if ($rs->statusCode == 0) {
  print_r($rs->result);
} else {
  print_r($rs);
}

Step 3. Run php demo.php

Create the relevant code file delete_target.py, modify the global variables, and then run

pip install requests
python delete_target.py

import time
import hashlib
import requests

# --- Global variable configuration ---
API_KEY = "YOUR_API_KEY"
API_SECRET = "YOUR_API_SECRET"
APP_ID = "YOUR_APP_ID"
HOST = "https://crs-cn1.easyar.com" 
TARGET_ID = "TARGET_ID"

def main():
    timestamp = str(int(time.time() * 1000))
    
    params = {
        'apiKey': API_KEY,
        'appId': APP_ID,
        'timestamp': timestamp
    }

    sorted_keys = sorted(params.keys())
    sign_str = "".join([f"{k}{params[k]}" for k in sorted_keys]) + API_SECRET
    signature = hashlib.sha256(sign_str.encode('utf-8')).hexdigest()

    url = f"{HOST}/target/{TARGET_ID}"
    final_params = {**params, 'signature': signature}

    print(f"Requesting DELETE {url}...")
    response = requests.delete(url, params=final_params)
    print(f"Response: {response.text}")

if __name__ == "__main__":
    main()

Create a new related code file main.go, modify global variables, then run

go run main.go

main.go:

package main

import (
  "crypto/sha256"
  "fmt"
  "io"
  "net/http"
  "sort"
  "strconv"
  "time"
)

var (
  ApiKey    = "YOUR_API_KEY"
  ApiSecret = "YOUR_API_SECRET"
  AppId     = "YOUR_APP_ID"
  Host      = "https://crs-cn1.easyar.com"
  TargetId  = "TARGET_ID"
)

func main() {
  ts := strconv.FormatInt(time.Now().UnixNano()/1e6, 10)
  params := map[string]string{
    "apiKey":    ApiKey,
    "appId":     AppId,
    "timestamp": ts,
  }

  keys := make([]string, 0, len(params))
  for k := range params { keys = append(keys, k) }
  sort.Strings(keys)

  builder := ""
  for _, k := range keys { builder += k + params[k] }
  builder += ApiSecret
  signature := fmt.Sprintf("%x", sha256.Sum256([]byte(builder)))

  url := fmt.Sprintf("%s/target/%s?apiKey=%s&appId=%s&timestamp=%s&signature=%s", 
    Host, TargetId, ApiKey, AppId, ts, signature)
  
  req, _ := http.NewRequest("DELETE", url, nil)
  resp, _ := http.DefaultClient.Do(req)
  defer resp.Body.Close()
  body, _ := io.ReadAll(resp.Body)
  fmt.Printf("Response: %s\n", string(body))
}

Add dependencies in cargo.toml.

Execute cargo run.

use sha2::{Sha256, Digest};
use std::collections::BTreeMap;
use std::time::{SystemTime, UNIX_EPOCH};

const API_KEY: &str = "YOUR_API_KEY";
const API_SECRET: &str = "YOUR_API_SECRET";
const APP_ID: &str = "YOUR_APP_ID";
const HOST: &str = "https://crs-cn1.easyar.com";
const TARGET_ID: &str = "YOUR_TARGET_ID";

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let ts = SystemTime::now().duration_since(UNIX_EPOCH)?.as_millis().to_string();

    let mut params = BTreeMap::new();
    params.insert("apiKey", API_KEY);
    params.insert("appId", APP_ID);
    params.insert("timestamp", &ts);

    let mut sign_str = String::new();
    for (k, v) in &params {
        sign_str.push_str(k);
        sign_str.push_str(v);
    }
    sign_str.push_str(API_SECRET);
    
    let mut hasher = Sha256::new();
    hasher.update(sign_str.as_bytes());
    let signature = hex::encode(hasher.finalize());

    let url = format!("{}/target/{}?apiKey={}&appId={}&timestamp={}&signature={}", 
                      HOST, TARGET_ID, API_KEY, APP_ID, ts, signature);
    
    let res = reqwest::Client::new().delete(url).send().await?;
    println!("Response: {}", res.text().await?);
    Ok(())
}

Create .net console project.

dotnet new console
dotnet run

using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Net.Http;

class Program {
    static string API_KEY = "API_KEY";
    static string API_SECRET = "API_SECRET";
    static string APP_ID = "APP_ID";
    static string HOST = "https://crs-cn1.easyar.com";
    static string TARGET_ID = "TARGET_ID";

    static async System.Threading.Tasks.Task Main() {
        string timestamp = DateTimeOffset.Now.ToUnixTimeMilliseconds().ToString();

        var dict = new SortedDictionary<string, string> {
            { "apiKey", API_KEY },
            { "appId", APP_ID },
            { "timestamp", timestamp }
        };

        StringBuilder sb = new StringBuilder();
        foreach (var kv in dict) sb.Append(kv.Key).Append(kv.Value);
        sb.Append(API_SECRET);
        
        string signature = Sha256(sb.ToString());

        using var client = new HttpClient();
        string query = string.Join("&", dict.Select(x => $"{x.Key}={x.Value}")) + $"&signature={signature}";
        string url = $"{HOST}/target/{TARGET_ID}?{query}";
        
        var response = await client.DeleteAsync(url);
        Console.WriteLine($"Result: {await response.Content.ReadAsStringAsync()}");
    }

    static string Sha256(string str) {
        byte[] bytes = SHA256.HashData(Encoding.UTF8.GetBytes(str));
        return BitConverter.ToString(bytes).Replace("-", "").ToLower();
    }
}

Runtime environment
- Unity 2020 LTS or later
- Scripting Backend: Mono or IL2CPP
- API Compatibility Level: .NET Standard 2.1 (recommended)

Step 1: Prepare image files

Create directories in the Unity project:

Assets/
└── Scripts/
     └── DeleteImageTarget.cs

Follow the Assets directory name
- Copy the sample code DeleteImageTarget.cs below

using System.Collections;
using UnityEngine;
using UnityEngine.Networking;

public class DeleteImageTarget : MonoBehaviour
{
    [Header("Config")]
    public string targetId = "Your targetId";
    public string apiBaseUrl = "https://Your-Server-end-URL";
    public string authorizationToken = "YOUR API KEY AUTH TOKEN"; 
    public string crsAppId = "CRS-AppId"; 

    private void Start()
    {
        StartCoroutine(DeleteTarget());
    }

    private IEnumerator DeleteTarget()
    {
     
        string url =
            $"{apiBaseUrl}/target/{targetId}?appId={crsAppId}";

        UnityWebRequest request = UnityWebRequest.Delete(url);
        request.downloadHandler = new DownloadHandlerBuffer();

        request.SetRequestHeader("Content-Type", "application/json");
        request.SetRequestHeader("Authorization", authorizationToken);

        yield return request.SendWebRequest();

        if (request.result == UnityWebRequest.Result.Success)
        {
            Debug.Log("Delete target success:");
            Debug.Log(request.downloadHandler.text);
        }
        else
        {
            Debug.LogError("Delete target failed:");
            Debug.LogError(request.error);
            Debug.LogError(request.downloadHandler.text);
        }
    }
}

In the Unity Editor:
- Create an empty GameObject
- Name it DeleteTarget
- Drag the DeleteImageTarget script onto the object

Step 3: Configure parameters (Inspector)

Modify in the Inspector panel:
- Api Url
- Authorization Token
- Crs App Id
- Target Id: The targetId of the image target to be deleted
Only these items need modification before running. Fill in the parameters prepared in the checklist.

Step 4: Run

Click Play
Check results in the Console:
- Success: Returns JSON (including targetId)
- Failure: HTTP/error message