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2 posts tagged with recording by rongorongo.
Displaying 1 through 2 of 2.

Electrical fluctuations as a watermark for audio and video recordings

Audio recordings usually include a low-level background noise caused by electrical equipment. The hum contains small frequency fluctuations which are propagated consistently over entire power grids. By storing the pattern of grid-wide fluctuations in a database forensics experts are able to use the hum as a watermark. This can determine when the recording was made, where it was made and whether it was recorded in a single edit. [more inside]
posted by rongorongo on Dec 12, 2012 - 43 comments

The Man Who Invented Stereo

In a single 1931 document, electrical engineer Alan Blumlein patented stereo records, stereo movie sountracks and surround sound. His equipment was used to make some of the first stereo recordings at EMI's Abbey Road studios - several decades before the technology came into popular use. Blumlein went on to pioneer 405 line TV (the first wholly electronic format which won out over John Logie Baird's rival system) and to produce the equipment that made the first outside TV broadcast possible. At the outbreak of World War 2 he was a key architect of the secret H2S radar project. Unfortunately he was killed in a plane crash while testing the technology and the whole incident was kept secret. Hence he remains an obscure figure despite his achievements. A recent BBC Radio 4 program contains a lot of the archive stereo footage and tells his story.
posted by rongorongo on Aug 7, 2008 - 5 comments

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