Can I get an entry to Hongkong without Visa? Is it valid?

I will fly from Japan to Kolkata but have a halt in Hongkong for few hours. If from Hongkong to Kolkata, I postpone my ticket for 2 days and want to stay in Hongkong for 2 days, will Hongkong visa be required? If yes can I get it from Japan? Currently I have Indian Passport.