Start-up ooVoo is hoping to take on everybody from Skype, the Internet telephony arm of eBay, to Cisco Systems with a new video conferencing offer for small businesses.

While Skype has the higher profile, New York-based ooVoo has quietly built up 7.5 million registered users in the last few years with a service that supports video chats between up to six people and up to six phone participants.

Now, the fledgling company is adding a desktop sharing option that will let business colleagues view each other’s computer screens and enable remote collaboration. It will also block advertising for business users who pay a monthly fee.

“We took what we had with the consumer and packaged it with a business plan,” said ooVoo CEO Philippe Schwartz who said that about 20 percent of the company’s current users were business customers even before its business-targeted plan.

Cisco’s development of a telepresence video conferencing system, which uses large screens and shows life-like images, has created renewed interest in video communications in recent years. But such systems cost thousands of dollars to install, at a time small businesses are looking to shave costs.

A few years ago, Cisco also bought firm WebEx, which lets people share documents and collaborate online.

Schwartz hopes to double ooVoo’s customer base this year and increase business users to as much as 40 percent of total customers as companies look to cut costs in a weak economy.