如何在php中将图像路径引用到数组值？

Question

So it is pretty tough to explain my problem. But ill do my best so u can understand

I am currently using this ocr api (http://ocrapiservice.com/) to retrieve text from images. They have provided api for all platforms. I have chosen php. the code is here

In the program example.php , 5-line :

'image'        =>    '@img.jpg',

1. is "img.jpg" in the current directory folder of the php ?

2. I have used the exact code even uploading img.jpg to directory but could not retrieve the image path.

3. I cannot upload the image , how should I refer the image path to it?

4. why did he use @ in '@img.jpg'?

   I tried all possible ways but couldn't proceed. Please help .