Library of Congress to use image tool for sound restoration
- By Aliya Sternstein
- Feb 13, 2006
Library of Congress officials are hoping that an experimental image workstation will speed the digitization and preservation of 78 rpm shellac and acetate records.
Scientists at the Lawrence Berkeley National Laboratory developed the system, Image, Reconstruct, Erase, Noise, Etc. (IRENE) to help preservationists restore at-risk recordings and improve audio quality. IRENE will generate high-resolution digital maps of the grooved surface of recordings, allowing preservationists to remove debris and extraneous sounds that contribute to the deterioration of recordings.
“Once we put the record in the form of an image, we can retouch the image and repair the damaged portion,” said Carl Haber, a senior scientist at Lawrence Berkeley National Laboratory who is leading the development of the technology. This aspect of the technology is a form of restoration software, the kind a photo lab would use in retouching a model’s looks for a cover shot.
The system is called IRENE as a nod to the first music record that the Berkeley lab team scanned – The Weavers’ “Goodnight Irene,” Haber said.
Library officials want to see if IRENE can rapidly convert 78 rpm shellac and acetate discs this spring at the agency’s National Audio-Visual Conservation Center in Culpeper, Va.
This month officials began transporting 80,000 45-rpm vinyl records — the Library’s whole 45 rpm collection — for storage at an underground, Cold War-era facility at the center, a former Federal Reserve building, said Gene DeAnna, head of the Library’s recorded sound section. The Library is retrofitting the 1960s facility that was built as living quarters for staff and vaults for huge sums of cash. “The idea was to have enough money to jump-start the economy after an atomic attack,” DeAnna said.
By early 2007, Library officials expect to begin digitally preserving the audiovisual collections in an adjacent conservation building. The order for digitizing the collections depends on the fragility of the format and researcher requests.
The center will store the Library’s audio artifacts and digital doppelgangers so that researchers can quickly retrieve and play them via a secure internal network. The recordings have copyright protections that prohibit Internet broadcasts.
Once the materials are safely in place, the center’s employees will be able to pull a record and deliver it to the audio preservation lab in the conservation building. Technical specialists will then digitize the audio as a high-resolution copy for preservation and a lower-resolution copy for Library users.
The conversion process can be lengthy. For example, the batch of recordings slated to be shipped this month contains oldies music from the ’50s, ’60s and early ’70s in single record format that technicians must individually play back and reformat. So when a researcher requests a song, the employee must first play the recording on a turntable connected to a computer and then send the file to the Library.
For compact discs, high-speed duplication is impossible. Cassette tapes copied at high speeds have lower sound quality, making high-speed duplication unacceptable for preservation. And the digitize-on-demand process means researchers may need to wait a day for their requests.
However, IRENE’s capacity to eventually reconstruct 78 rpm records with imaging could revolutionize sound preservation practices. “You can put a broken record together by reassembling the pieces,” Haber said.
The Berkeley lab team has made marked advances with the technology. During early tests a couple years ago, it took 40 minutes to scan one second of audio. Now, it is possible to scan one second of audio in a few seconds.
The sound restoration project is the result of a two-year grant from the National Endowment for the Humanities that began last spring. Haber and the team were awarded funding to construct and test an imaging machine for the Library’s recorded sound section and preservation directorate. The Berkeley lab team has already put the pieces of the machine together and demonstrated that the technology works. Now, the challenge is to write software that is intuitive enough for Library technicians with basic training to master.
The goal is that “they would load a disc on the machine and the machine would automatically set up the parameters of the measurements and scan the data pretty much automatically,” Haber said.
However, at least one private record collector is against the Library’s massive digitization plan. Paul Mawhinney has accumulated a collection of more than 3 million recordings for his Pittsburgh-based Recordrama Sound Archives. He said the Library is overlooking a significant drawback to digital preservation.
“I think that the actual collection in vinyl is actually far superior to digital format,” he said. “Nobody knows how long [digital] is going to last.”
Library officials scoffed at the notion of storing recordings in vinyl. They said they would continue to rely on the advice of professional audio archivists, who say that the best means of preserving audio is to convert it into a high-resolution digital file and then manage the file safely in a repository system.
“Vinyl certainly is stable but if you play it, it’s an invasive process,” DeAnna said. “Dropping a needle on a record is an invasive process. No one sees recording to vinyl as a preservation process. What happens when there aren’t any turntables to play it?”