Ex-girlfriend can get video deposition of Sumner Redstone in upcoming trial-judge

May 2 (Reuters) - Media mogul Sumner Redstone can be deposed at home in a videotaped session ahead of a trial to resolve his ex-girlfriend's lawsuit over his mental competence, a California judge ruled tentatively on Monday.

Lawyers for Redstone's former companion, Manuela Herzer, had requested that the 92-year-old billionaire be called as a witness in the trial, which starts on Friday.

Los Angeles Superior Court Judge David Cowan said, however, that the playing of the video at trial would not be open to the public.

Herzer claims Redstone, the controlling shareholder of media companies Viacom Inc and CBS Corp, was not mentally competent last October when he replaced her as his designated health care agent.

Viacom and CBS shareholders have closely followed the lawsuit for what it could reveal about Redstone's condition.

(Reporting by Lisa Richwine; Editing by Bill Rigby)