has anyone benchmarked qoa to see roughly how many instructions per sample it needs? all i see here is that it's more than adpcm and less than mp3, but those differ by orders of magnitude
like, can you reasonably qoa-compress real-time 16ksps audio on a 16 megahertz atmega328?
hmm, https://phoboslab.org/log/2023/04/qoa-specification has some benchmark results, let's see... seems like he encoded 9807 seconds of 44.1ksps stereo in 25.8 seconds and decoded it in 3.00 seconds on an i7-6700k running singlethreaded. what does that imply for other machines?
it seems to be integer code (because reproducibility between the predictor in encoding and decoding is important, and a significant part of it is 16-bit. https://ark.intel.com/content/www/xl/es/ark/products/88195/i... says it's a 4.2 gigahertz skylake. agner says skylake can do 4–6 ipc (well, μops/cycle) https://www.agner.org/optimize/blog/read.php?i=628, coincidentally testing on an i7-6700k himself, but let's assume it's 3 ipc, because it's usually hard to reach even that level of ilp in useful code
so that's about 380 μops per sample if i'm doing my math right; that might be on the order of 400 32-bit integer instructions per sample on an in-order processor. if (handwaving wildly now!) that's 600 8-bit instructions, the atmega328 should be able to encode somewhere in the range of 16–32 kilosamples per second
so, quite plausibly
for decoding the same math gives 43 μops per sample rather than 380
i'm very interested to hear anyone else's benchmarks or calculations