It feels like a cassette revival comes along every few years, and with the latest iteration in full swing, we were both startled and amused to see that at least one inventor is re-exploring the idea of using audio cassettes for data storage. Behold: a home-built device called the “Digital-Analog Tape Picture Recorder” (yes, it needs a better name), which is basically a camera that records its images onto tape.
The image is captured with an ESP-32 CAM, which is a nifty little device in its own right, combining a 2-megapixel camera, a 32-bit processor, and an SD card slot in a system-on-a-chip package that retails for less than $20. The onboard camera makes these perfect for use in Internet of Things devices for security monitoring, home automation, etc., which is where they’re most often found.
This little device, however, does something different. As inventor Jordan Blanchard demonstrates in a YouTube video, the camera’s processor encodes the image as an analog signal, which is then recorded onto the tape in the attached cassette deck. The image is then decoded back into a digital signal by a Raspberry Pi and sent to the device’s built-in display. (Also worth noting: the code for encoding the image into an analog format was inspired by a method developed for sending images back from high-altitude weather balloons.)
Anyone old enough to remember actually using cassettes for storage—a demographic that, sadly, includes your correspondent—will probably raise their eyebrows at the idea of doing so, voluntarily, in the year 2026. For a start, both writing to and reading from cassette were painfully slow processes in the early ‘80s, and they feel positively prehistoric in the 21st century. The images are captured at 320×256, well below the camera’s maximum resolution, and it still takes a good couple of minutes for the device to encode, record, playback, and decode the image for display; it’s so slow, in fact, that you can watch the Raspberry Pi decoding each individual row of pixels if you want.
But complaining about the speed of a tape deck feels like missing the point—obviously, there are a gazillion other ways you could build a camera, and the use of a tape here is a deliberate choice made a) for fun and b) for artistic effect. On the latter point, the resultant images (above) look like they’ve stepped straight out of an indie horror game, full of analog distortion and creepy VHS-esque artifacts introduced in both recording and, especially, during playback. Blanchard’s description explains why: “Tape speed is never perfectly stable (and even worse with a cheap tape deck), [causing] frequency drift and sync dropouts.”
The obvious question here is whether you can also listen to the image, and the answer is “yes”. The device has an audio output, and at one point, Blanchard switches it on briefly to let us hear the signal. If you’re expecting a dial-up-modem-esque cacophony, you might be surprised to hear a gently undulating waveform that wobbles somewhere around F#5, or 1480 Hz. This made us wonder: can we use this to work out how fast the tape is transferring data?
Again, the answer is “yes”! According to this handy calculator, 1480 Hz means a data throughput of about 5.12 Kpbs. (For comparison, my awful wifi connection does 405 Mbps, making it about 81,000 times faster.) Anyway, back-of-the-envelope calculations aside, Blanchard’s device is a fascinating piece of old-meets-new technology AND a welcome reminder of why floppy disks felt like a goddamn revelation in the mid-1980s. It’s fun to play with cassettes, listen to them in your car, make mixtapes, etc.—but thank god we don’t have to rely on them for anything anymore.
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