Two recordable DVD technologies will be on offer later this year in an echo of the old Betamax-VHS battle for VCR market share.

First to launch will be a 4.7GB version of the DVD-RAM technology supported by Hitachi, Toshiba and Panasonic. Current DVD-RAM drives store only 2.6GB per side. Panasonic, a consumer arm of Matsushita, showed a 4.7GB LF-D201E DVD-RAM drive which is due to ship this month. But its recordings cannot be read by all DVD Video and DVD-ROM players.

Seinosuke Karaku, head of Matsushita Europe, said it was hoped that future drives will read the format as standard. DVD-RAM has the advantage of being first to the market and current 2.6GB drives cost only £299.

A rival DVD+RW technology, backed by Hewlett-Packard, Philips, Sony, Mitsubishi, Ricoh and Yamaha, claims to be compatible with existing DVD players and DVD-ROM drives; also its discs do not use protective cartridges like those of its rival.

First-generation 3GB +RW drives never reached the market, but 4.7GB versions will start to ship late this year, a CeBIT press conference was told.

Philips and Ricoh both demonstrated DVD+RW recordings playing on different makes of player, both standalone and on a PC. The Philips drive will ship late this year for around £,250, said Robert van Eijk, vice president of strategic alliances.

Anti-piracy measures have been a major issue in DVD development. Eijk said DVD packed enough protective measures to discourage casual illegal copying, but perhaps not the professional pirate. "No fence is high enough for that," he said.