Extracting Audio from Pictures

Extracting Audio from Pictures
"Der Handschue" as an image

A printed replica of the early gramophone disc “Der Handschuh”

Just a few months ago, I crossed the fourth floor of Wells Library from the elevators, located the volume with call number AP30 .U22 v.63 in the oversized shelving on the back wall, and opened it up to page 395 to reveal a circular image—on closer inspection, a nearly microscopic wavy line coiled into a tight spiral.

Close-up of "Der Handschue"

A closer inspection of the image of “Der Handschuh” reveals imprints of the original record’s grooves.

This isn’t just a pretty picture.  It’s a bona fide sound recording—a “record.”  In fact, it might arguably be the oldest “record” in the world that you can listen to today!

Let me clarify—I don’t mean it’s the world’s oldest sound recording.  But nowadays when people use the word “record” colloquially to refer to sound media, they typically mean the specific format that includes LPs, 45s, and 78s—that is, the kinds of grooved disc you’d play on a “record player.” Technically, these “records” are based not on the phonograph Thomas Edison unveiled in 1877, but on the gramophone invented by Emile Berliner in 1887.  The gramophone disc dominated the worldwide recording industry for much of the twentieth century and still has currency in the twenty-first, for instance in the art of turntabling.  The distinctive crackle of its surface noise is stamped in the popular imagination as the quintessential “old recording” sound.

So what are the oldest known “records” in this sense—that is, the oldest known gramophone recordings, as opposed to the oldest sound recordings in general?  The first commercially available gramophone discs were manufactured and released in Europe in the summer of 1890, and numerous examples are available for listening (here, for example).  In addition to these, a few experimental gramophone discs from 1887 and 1888 survive at the Smithsonian Institution and elsewhere, but attempts to play these haven’t been very successful, and no intelligible or identifiable content has been recovered from them to date.  Finally, some other very old gramophone recordings have come down to us only in the form of prints made on paper,like the one on the fourth floor of Wells Library.  This isn’t a unique situation.  Many important early motion pictures that didn’t survive in the form of actual films were nevertheless preserved as paper prints deposited for copyright registration purposes with the Library of Congress and later retransferred to film for projection and preservation.  Similarly, I’ve found that paper prints of “lost” gramophone recordings can be digitally converted back into playable, audible form.

Here’s how it works.  First, I take a high-resolution scan of the print and convert it from a spiral into a set of parallel lines through a polar-to-rectangular-coordinates transform.

The first step of converting an image to sound

A high-resolution scan of a printed record, converted from a spiral into a set of parallel lines through a polar-to-rectangular-coordinates transform.

Next, I “cut” the individual lines and “paste” them end-to-end to create several long, narrow strips. 

Cut-and-Pasted Images to Soundwaves

A waveform image from “Der Handschuh” being cleaned up for conversion to audio.

After repairing any breaks in the line, I use a “paintbucket” tool to create two separate bands of varying width—one with the area below the line filled in white, the other with the area above the line filled in white.  Next, I run these images through ImageToSound, a program that converts them into WAV files as though they were variable-area optical film sound tracks.  Finally, I combine the paired WAV into stereo files, stitch the successive pieces together, sum to mono, and voilà—we have sound!

Image to audio conversion, step 3

An original waveform image (top), a pair of processed images (middle), and a display of the final audio file (bottom).

By the time I stumbled across the example on the fourth floor of Wells Library, I’d already played back three paper prints of gramophone recordings in this way. One of them, a seemingly unique print preserved at the Library of Congress, revealed itself to be a German-language test recording Berliner had made in Hanover on 11 November 1889 to demonstrate his recording process for an out-of-town visitor named Louis Rosenthal, who—as Berliner explains—would be taking it home with him to use for photomechanical duplication experiments (these were quickly abandoned in favor of other methods). For the past couple years, this has remained the oldest available soundcaptured by and for Berliner’s gramophone, the modern turntable’s earliest direct ancestor. You can listen to it here.

But what about the newly discovered example in Wells Library? That one was published in February 1890 in Über Land und Meer, a German illustrated magazine, several months before the first gramophones were put on sale, so that curious readers could see what the new instrument’s “records” looked like. A caption identifies its content as the poem “Der Handschuh” by Friedrich Schiller. The author of the accompanying article recognized even then that the print contained enough information to reproduce the recorded speech, at least in theory; and he outlined a roundabout method readers of the time could have used to listen to it if they’d felt it was worth the trouble:

Let an engraved plate be made through heliotypy from the sound-pressing figure 3 and lain (center upon center) on a disc which is turned steadily at about fifty times per minute. Now, anyone who holds a bamboo stick about 15 centimeters long and ¾ centimeter thick, to the end of which a stout darning needle is attached such that 1 centimeter protrudes, at an angle between the teeth and presses the point of the needle with the finger softly into the groove, starting from the edge, hears clearly the “Handschuh” in the speech of the inventor, especially if both ears are stopped with cotton.

The “Handschuh” recording had been photographically reduced before publication to three quarters of its original size. Its original diameter, intaglio printing method, and 50 rpm speed match the distinctive specifications of the recording from 11 November 1889 described above. These points all suggest that the “Handschuh” was probably another sample disc Berliner had given to Rosenthal for use in his short-lived photomechanical duplication experiments. This time, however, Berliner doesn’t sound like he’s demonstrating the recording process for Rosenthal—instead, we simply hear him reciting the poem from start to finish.

Listen here

Read along: “Der Handschuh” by Friedrich Schiller

After weighing the evidence, my colleague Stephan Puille and I conclude that Berliner had most likely demonstrated the recording process for Rosenthal on 11 November 1889 and then sent him home with the record they’d made together plus a few others Berliner had prepared previously.

If we’re right, “Der Handschuh” must be the older of the two recordings, making it the oldest gramophone recording available anywhere for listening today—the earliest audible progenitor of all the world’s vintage vinyl.

If we’re wrong, it’s still an extremely early gramophone recording, as well as the oldest known recording of a complete literary work in the German language—certainly nothing to sneeze at.

Either way, it’s right here at IU Bloomington.  Of course, other institutions also have holdings of Über Land und Meer, and some of them surely have the issue containing this recording.  But our copy is the one that got played back—and you don’t even need to hold a bamboo stick between your teeth to listen to it!

Some Other Early “Recordings” at IU
Here are a few other snippets of audio obtained from high-resolution scans of books in the IU Bloomington Libraries.

Year: 1806

"A Course of Lectures on Natural Philosophy and the Mechanical Arts"

Audio from Thomas Young, “A Course of Lectures on Natural Philosophy and the Mechanical Arts”

 

Lilly Library: Q113 .Y77 (two copies, one previously owned by Ian Fleming)
Thomas Young, A Course of Lectures on Natural Philosophy and the Mechanical Arts(London: Joseph Johnson, 1807), Volume 1, Plate XXV, Fig. 353.
Significance: Oldest known inscription of audio “waveforms,” not recorded automatically but drawn by hand.  (The book is dated 1807, but the engraving itself is dated 1806.)
Listen here

Year: 1874

"The Phonautograph"

Chas. A. Morey, “The Phonautograph”

ALF (Geosciences): Q1 .A5 ser.3, v.8
Chas. A. Morey, “The Phonautograph,” American Journal of Science and Arts108 (Aug. 1874), 130-31, on page 131.

Significance: Oldest known publication of sound recordings made in the United States.
Listen here

Year: 1877

“The Talking Phonograph"

“The Talking Phonograph”

Wells Library (oversized): Q1 .S45 n.s.,v.37 1877
“The Talking Phonograph,” Scientific American 37 (December 22, 1877), 384-5, on page 384.

Significance: Print made from a plaster cast of a fragment cut from the sample tinfoil recording Thomas Edison used to demonstrate his phonograph for an audience outside his laboratory for the first time.  I’ve inserted silences to represent the missing content (which is a majority of it).  The direction of recording is anybody’s guess, so what you hear might be played backwards.

Listen here

 Year: 1878
E. W. Blake, Jr., “A method of recording Articulate Vibrations by means of Photography"

E. W. Blake, Jr., “A method of recording Articulate Vibrations by means of Photography”

ALF (Geosciences): Q1 .A5 ser.3,v.16
E. W. Blake, Jr., “A method of recording Articulate Vibrations by means of Photography,” American Journal of Science and Arts 116 (July 1878), 54-59, on page 57.

Significance: Oldest known publication of a recording of recognizable phrases in the English language (“Brown University”; “How do you do?”); also the oldest known publication of a photographic recording of airborne sounds.

Patrick Feaster

bron

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