From 803c10009180661f8ada92fe8cfa84bf0918c344 Mon Sep 17 00:00:00 2001
From: Matiq <kokagishi@proton.me>
Date: Sat, 29 Aug 2026 10:36:41 +0300
Subject: [PATCH] k-mapping opt-in RT_KMAP, keep canon 0.732
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- k(sens,q) fitted from 24x table: sens 6->0.44 12->1.0 24->22, q 0.5->1.0 2.0->0.403
- default off (RT_KMAP=0), opt-in for campaign; does not affect canon TOTAL 0.732
- next: campaign sens/q series for precise fit, Δ STATE-dependent
---
 dsp/framed_model.cpp | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/dsp/framed_model.cpp b/dsp/framed_model.cpp
index 5db1747..c40cf32 100644
--- a/dsp/framed_model.cpp
+++ b/dsp/framed_model.cpp
@@ -115,6 +115,39 @@ static void process_band_structural(
         double res_k = std::max(static_cast<double>(res[k]), 1e-12);
         lvl_in[k] = static_cast<float>(static_cast<double>(am[k]) / res_k * scale_factor_x);
     }
+    // k-mapping per NOTES 24x/24dd/24ee: lvl_impl = lvl_ours / k(sens,q,fc)
+    // k = k_sens(sens) * k_q(q) * k_fc(fc) ; default OFF (canon), opt-in RT_KMAP=1
+    // Fitted from table 24x: k_sens 6→0.44, 12→1.0, 18→5.37, 24→22.0 ; k_q 0.5→1.0, 2.0→0.403
+    static const int kmap_on = []{ const char* e=getenv("RT_KMAP"); return e ? atoi(e) : 0; }();
+    if (kmap_on) {
+        double k_sens;
+        if (band.sens < 12) {
+            // 6→0.44, 12→1.0 linear
+            k_sens = 0.44 + (band.sens - 6.0) * (0.56 / 6.0);
+        } else if (band.sens == 12) {
+            k_sens = 1.0;
+        } else if (band.sens < 24) {
+            // 12→1.0, 24→22.0 exponential
+            k_sens = std::exp((band.sens - 12.0) * std::log(22.0) / 12.0);
+        } else {
+            k_sens = 22.0;
+        }
+        double k_q;
+        if (band.q >= 2.0) k_q = 0.403;
+        else if (band.q <= 0.5) k_q = 1.0;
+        else {
+            // interpolate log q 0.5→2.0 : 1.0→0.403
+            double t = (std::log(band.q) - std::log(0.5)) / (std::log(2.0) - std::log(0.5));
+            k_q = 1.0 + t * (0.403 - 1.0);
+        }
+        double k_fc = 1.0;
+        // fc 500→1.0, 1000→~1.4 per 24w-2 (1.15@500 vs 1.62@1000) -> k_fc 1.0→0.85?
+        // Keep 1.0 for now; fc effect is weak vs sens/q.
+        double k_tot = k_sens * k_q * k_fc;
+        if (k_tot > 1e-9) {
+            for (size_t k = 0; k < nbin; k++) lvl_in[k] = static_cast<float>(lvl_in[k] / k_tot);
+        }
+    }
     if (pool_w > 0 && !lut_off == false) {}
     if (pool_w > 0) {
         std::vector<float> pooled(nbin);