A LD-ROM is a data storage format extension of the laserdisc

Laserdisc

LaserDisc was a home video format and the first commercial optical disc storage medium. Initially licensed, sold, and marketed as MCA DiscoVision in North America in 1978, the technology was previously referred to interally as Optical Videodisc System, Reflective Optical Videodisc, Laser Optical...

. A LD-ROM

Read-only memory

Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...

 could store sixty minutes of analog audio and video with 540 megabyte

Megabyte

The megabyte is a multiple of the unit byte for digital information storage or transmission with two different values depending on context: bytes generally for computer memory; and one million bytes generally for computer storage. The IEEE Standards Board has decided that "Mega will mean 1 000...

s of digital data where the digital audio

Digital audio

Digital audio is sound reproduction using pulse-code modulation and digital signals. Digital audio systems include analog-to-digital conversion , digital-to-analog conversion , digital storage, processing and transmission components...

 soundtrack would be.

This format was used mainly by the Pioneer

Pioneer Corporation

is a multinational corporation that specializes in digital entertainment products, based in Kawasaki, Kanagawa, Japan. The company was founded in 1938 in Tokyo as a radio and speaker repair shop...

 LaserActive

Pioneer LaserActive

The Pioneer LaserActive was a short-lived Laserdisc-based game console released by Pioneer in 1993. In addition to LaserActive games, separately sold add-on modules expanded the hardware to include compatibility with the Sega Mega Drive/Sega Genesis and PC Engine/TurboGrafx 16 game cartridges and...

 interactive laserdisc player/game console, which had several video games available for it in the LD-ROM format.

An earlier, but essentially identical, version of LD-ROM developed by Philips

Philips

Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

 called LV-ROM (LaserVision Read Only Memory, "LaserVision" being Philips' own brand name for the laserdisc technology), was used for the BBC Domesday Project

BBC Domesday Project

The BBC Domesday Project was a partnership between Acorn Computers Ltd, Philips, Logica and the BBC to mark the 900th anniversary of the original Domesday Book, an 11th century census of England...

 for the storage of analog video/audio and digital data on a laserdisc. The data area of the disc was read by a special Philips LV-ROM drive connected to a BBC Master

BBC Master

The BBC Master was a home computer released by Acorn Computers in early 1986. It was designed and built for the British Broadcasting Corporation and was the successor to the BBC Micro Model B. The Master 128 remained in production until 1993....

 computer, and then processed and overlaid by way of genlock

Genlock

Genlock is a common technique where the video output of one source, or a specific reference signal from a signal generator, is used to synchronize other television picture sources together. The aim in video and digital audio applications is to ensure the coincidence of signals in time at a...

by the computer as text & menus over the analog video from the disc.