EQ smoothing: replace pow(10, x/10) with exp(x · ln(10)/10)#2239
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EQ smoothing: replace pow(10, x/10) with exp(x · ln(10)/10)#2239
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Mathematically equivalent (pow(10, x) == exp(x * ln(10))) but typically 3-4× faster — std::exp is dramatically simpler than the fully-general std::pow path. At 1/3 octave smoothing this is the dominant cost in the smoothing pass: ~200 bins × 2 traces × 25 Hz analyzer ticks ≈ 10K calls/sec, so the saving is small in absolute terms but free. Suggested by aethersdr-agent reviewing #2236 post-merge.
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Mathematically identical (
pow(10, x) == exp(x · ln(10))) but ~3-4× faster on most stdlib implementations —std::expis dramatically simpler than the fully-generalstd::powpath.Inner loop in
applyFractionalOctaveSmoothing:Reverse direction (
10 * log10(meanLin)) stays as-is — it's outside the inner loop and only runs once per output bin.At 1/3 octave smoothing the savings are real but absolute cost is already low (~10K dB→linear calls per second). Cheap win.
Tests pass (
./build/client_eq_smoothing_test— all 15 assertions).Suggested by
aethersdr-agentreviewing #2236 post-merge.