SAN FRANCISCO (AP) - Netflix's Internet video service is adding more marquee attractions as it braces for a new competitive threat from cable-TV provider Comcast Corp.
    
As part of an effort to offer more exclusive material, Netflix locked up the right to show "The Artist" and other movies from The Weinstein Co. before the films are released to leading pay-TV channels such as

Showtime and HBO.
    
Just a few hours after Tuesday's announcement about that multiyear deal, Comcast unveiled plans to undercut Netflix with a less expensive version of a service that will stream old TV series and movies to devices with

high-speed Internet connections.
    
The Comcast service, called Xfinity Streampix, will be available this week to the company's subscribers.

It will cost $5 per month, below Netflix's $8 monthly price for its Internet-streaming service.

Some Comcast customers who pay for multiple services, including high-speed Internet access and phone, will get Streampix at no additional cost.
    
Although it appears Netflix's library is more extensive, Streampix could be good enough for some households looking to supplement their cable-TV service with a package that has on-demand video on computers

and mobile devices.
     
Comcast, which is based in Philadelphia, will join two other large companies, Amazon.com Inc. and Wal-Mart Stores Inc., already offering video streaming services. 

By countering Netflix, Comcast hopes to hold on to customers, many of whom have been canceling their cable subscriptions to save money.

Some of those former subscribers have been able to get their entertainment fixes from Netflix, whose Internet streaming service began this year with 21.7 million U.S. subscribers.