"Opus IV" is a digital reinterpretation of the 1925 homonymous film by Walter Ruttmann.
The video file is the original film by Ruttmann (on the Public Domain) downloaded from archive.org/details/LichtspielOpusIV The sound was generated from the video frames. Even it could be considered a sonification work, or even a generative work, the audio files and the image files are exactly the same, you hear what you see. The process of creation consisted on saving all the 7.755 frames from the original film first as .raw and then as .aiff.
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