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Ghosts in the MP3 File

GhostBusters

I have been importing all of my CD collection for the second, and hopefully last, time. When I first cut my CD collection, technology was rather primitive and after a number of listening tests I decided to cut my collection at 192kbps VBR. It was a compromise between processing speed and portability. I first converted my CD collection almost ten years ago.

Today I am cutting the collection as lossless 16/44.1 CD quality. The size of the files and the processing overhead are no longer an issue and I would rather have the CDs at full resolution.

The Ghost in the MP3 is a test of what gets left out during an MP3 encoding process:

The MPEG-1 or MPEG-2 Layer III standard, more commonly referred to as MP3, has become a nearly ubiquitous digital audio file format. First published in 1993, this codec implements a lossy compression algorithm based on a perceptual model of human hearing. Listening tests, primarily designed by and for western-european men, and using the music they liked, were used to refine the encoder. These tests determined which sounds were perceptually important and which could be erased or altered, ostensibly without being noticed. What are these lost sounds? Are they sounds which human ears cannot hear in their original context due to universal perceptual limitations or are they simply encoding detritus? It is commonly accepted that MP3’s create audible artifacts such as pre-echo, but what does the music which this codec deletes sound like? In the work presented here, techniques are considered and developed to recover these lost sounds, the ghosts in the MP3, and reformulate these sounds as art…

“moDernisT” was created by salvaging the sounds and images lost to compression via the MP3 and MP4 codecs. The audio is comprised of lost mp3 compression material from the song “Tom’s Diner” famously used as one of the main controls in the listening tests to develop the MP3 encoding algorithm. Here we find the form of the song intact, but the details are just remnants of the original. The video is the MP4 ghost of a corresponding video created in collaboration with Takahiro Suzuki. Thus, both audio and video are the “ghosts” of their respective compression codecs.