Blinkx launches ad service based on viewers' habits

* Introducing behavioural targeting on its site

* Will let users opt out, should boost ad rates

LONDON, April 27 (Reuters) - Online video search engine Blinkx Plc (BLNX.L) has launched a new version of its platform to offer more relevant marketing by matching an advert to a user based on their previous viewing habits.

Blinkx, which is based in San Francisco and London and says it is the world's largest and most advanced video search engine, currently runs a platform which matches adverts with video based on the video subject matter.

The new system will build a detailed profile of the individual user's habits, and from this, it will serve ads to users that fit with their interests. The first brand Blinkx expects to work with is Toyota.

Blinkx Chief Executive Suranga Chandratillake said its new technology would allow it to understand its audience even further, which would give a better performance for the advertiser.

"Targeting is extremely valuable," he told Reuters. "What we saw, particularly during a recession, is that if you can target viewers then advertisers can justify higher spend.

"Targeting in general can be very powerful in keeping the (ad rate) pricing high."

Blinkx said its platform would monitor activity only on the Blinkx site, and would not store any personal details and search habits. All users on the site will also be able to opt out of the behavioural targeting aspect. (Reporting by Kate Holton; Editing by Paul Sandle)