Dear Sir,
As I understand that you need to crawl the image from the site by extracting the Request and simulate it in Java.
I have done many site scraping, crawling before. Here is my Google site scraping project:
https://www.freelancer.com/projects/Linux/Crawl-google-play-for-developer/
With my strong experience for web scraping, crawling. I will help you complete this project.
Please tell me if there is anything that prevent you from award me this project.
It is my pleasure to help you.
Thank you very much.