08-26-2020, 04:54 PM
update: It works!
For any interested in trying this themselves, this is my new process: Import settings in GIMP 2.10 should be "Gray 16-bit Little Endian", and the image's horizontal resolution should be a multiple of 20 (I don't understand why, but it works best this way). Normally, audacity will read the bmp backwards, but it will read the rows of the image forwards, which leads to some interesting distortion; if you wish, you can avoid this by flipping the image vertically before exporting it. The raw import setting for Audacity should be "Unsigned 8-bit PCM", and I haven't been able to detect any difference between Big or Little Endian in that stage of the process. The resulting wav file will be several times slower, but you can fix that easily by speeding it up.
Many thanks, Ofnuts!
For any interested in trying this themselves, this is my new process: Import settings in GIMP 2.10 should be "Gray 16-bit Little Endian", and the image's horizontal resolution should be a multiple of 20 (I don't understand why, but it works best this way). Normally, audacity will read the bmp backwards, but it will read the rows of the image forwards, which leads to some interesting distortion; if you wish, you can avoid this by flipping the image vertically before exporting it. The raw import setting for Audacity should be "Unsigned 8-bit PCM", and I haven't been able to detect any difference between Big or Little Endian in that stage of the process. The resulting wav file will be several times slower, but you can fix that easily by speeding it up.
Many thanks, Ofnuts!