CLAUDE: DNN de-streak (subtract-avg), compute-window, and recurrent feed

- curt_subtract_avg (+ -SUBAVG filename tag): subtract the input per-pixel temporal
  mean before LoG. Removes the static treeline edge (and so its 8px tile-grid
  horizontal streak and the first-LReLU amplification of it); the moving target is
  not in the average, so it survives. Uses the whole sequence (not realtime; realtime
  would use a prior-run average).
- DNN compute-window: the timing ROI (curt_time_from/to) now gates the DNN inference
  loop (only in-window scenes are inferred), not just the saved output - fast iteration
  on a target's few seconds.
- DNN -> recurrent layer: feed the DNN field to runRecurrentLevel (per selected level,
  curt_recur_*). curt_dnn_recur_splat toggles feed-as-is vs bilinear splat of each
  pixel's velocity vector to its fractional (px+dx,py+dy) so neighbours reinforce in one
  sub-pixel bin (-SPLAT mark). curt_dnn_recur_scale (default 10) lifts the [0,1] field
  (peaks ~0.1) to the recurrent's tuned rs_min~1.0 scale. splatField() helper added.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/main/java/com/elphel/imagej/cuas/rt/CuasDetectRT.java

@@ -98,6 +98,7 @@ public class CuasDetectRT {
 					}
 					String fpixels_name = Path.of(fpixels_file).getFileName().toString();
 					base_name = fpixels_name.substring(0,fpixels_name.length() - fpixels_suffix.length()); // By Claude on 06/11/2026
+					if (clt_parameters.imp.curt_subtract_avg) base_name += "-SUBAVG"; // distinct output filenames for average-subtracted runs (don't overwrite) // By Claude on 06/14/2026
 					if (clt_parameters.imp.curt_synth_src) { // load the synthetic reference grid separately (NOT mixed here) // By Claude on 06/14/2026
 						// Real (loaded above) is the pyramid base. The synthetic file holds NORMALIZED
 						// (peak 1) clean targets / a velocity-reference grid: load + scale it, keep it
@@ -249,6 +250,30 @@ public class CuasDetectRT {
 		return ((w[0] == 0) && (w[1] == a.length)) ? a : java.util.Arrays.copyOfRange(a, w[0], w[1]);
 	}
 
+	/** Re-bin each ROI pixel's velocity vector to its fractional offset position (px+dx, py+dy) via // By Claude on 06/14/2026
+	 *  bilinear splat, so neighbours that both claim one sub-pixel target reinforce in the same bin.
+	 *  field[roi_pix][nsub][nvel]; off[roi_pix][{dx,dy,s}] (may be null). Returns a new field. */
+	private static double [][][] splatField(double [][][] field, double [][] off, Rectangle roi) {
+		int rw = roi.width, rh = roi.height, npix = field.length;
+		int nsub = field[0].length, nvel = field[0][0].length;
+		double [][][] out = new double [npix][nsub][nvel];
+		for (int p = 0; p < npix; p++) {
+			if ((off == null) || (off[p] == null)) continue;
+			double fx = (p % rw) + off[p][0], fy = (p / rw) + off[p][1];
+			int x0 = (int) Math.floor(fx), y0 = (int) Math.floor(fy);
+			double wx = fx - x0, wy = fy - y0;
+			for (int gy = 0; gy < 2; gy++) for (int gx = 0; gx < 2; gx++) {
+				int tx = x0 + gx, ty = y0 + gy;
+				if ((tx < 0) || (tx >= rw) || (ty < 0) || (ty >= rh)) continue;
+				double wgt = (gx == 0 ? 1.0 - wx : wx) * (gy == 0 ? 1.0 - wy : wy);
+				if (wgt <= 0) continue;
+				double [][] dst = out[ty * rw + tx], src = field[p];
+				for (int su = 0; su < nsub; su++) for (int v = 0; v < nvel; v++) dst[su][v] += wgt * src[su][v];
+			}
+		}
+		return out;
+	}
+
 	/** Level selector for the heavy per-level paths (3d3/conv5d, C5P-direct, DNN): // By Claude on 06/13/2026
 	 *  empty/null curt_c5_levels = all built levels, otherwise only the listed ones. */
 	private static boolean c5LevelSelected(int [] c5_levels, int nlev) { // By Claude on 06/13/2026
@@ -619,6 +644,14 @@ public class CuasDetectRT {
        		QuadCLTCPU.saveImagePlusInDirectory(imp_5d,getModelDirectory());
        	}
        	double [][] dpixels = getDPpixels();
+       	if (clt_parameters.imp.curt_subtract_avg && (dpixels != null) && (dpixels.length > 0)) { // de-streak: subtract the static background before LoG so the sharp treeline edge (and its tile-grid ringing) is gone; the moving target is not in the average // By Claude on 06/14/2026
+       		int npx = dpixels[0].length;
+       		double [] mean = new double [npx];
+       		for (double [] fr : dpixels) for (int p = 0; p < npx; p++) mean[p] += fr[p];
+       		for (int p = 0; p < npx; p++) mean[p] /= dpixels.length;
+       		for (double [] fr : dpixels) for (int p = 0; p < npx; p++) fr[p] -= mean[p];
+       		System.out.println(now()+" detectTargets(): subtracted temporal average over "+dpixels.length+" input frames (curt_subtract_avg - uses whole sequence; realtime would use a prior-run average)"); // By Claude on 06/14/2026
+       	}
        	double [][] dpixels_log = new double [dpixels.length][dpixels[0].length];
     	double []   kernel2d = cuasRTUtils.getKernel2d();
     	double alpha0 = 1.0 - clt_parameters.imp.curt_rleak0;
@@ -1202,6 +1235,28 @@ public class CuasDetectRT {
    						QuadCLTCPU.saveImagePlusInDirectory(ShowDoubleFloatArrays.showArraysHyperstack(
    								off_hyper, rwid, title_dnn+"-OFFSET", ts_dnn_w, new String[]{"dx","dy","s"}, false), getModelDirectory());
    					}
+   					// Feed the DNN field to the recurrent layer (Layer 2): as-is, or offset-splatted (px+dx,py+dy). // By Claude on 06/14/2026
+   					// Tune the recurrent blend with curt_recur_w (0.25/0.75) etc.; the field is [0,1]-scaled so rs_min may need lowering.
+   					if (run_recur && (num > 0)) {
+   						boolean splat = clt_parameters.imp.curt_dnn_recur_splat;
+   						double  rscale = clt_parameters.imp.curt_dnn_recur_scale;            // DNN field ~0.1 -> recurrent rs_min ~1.0 // By Claude on 06/14/2026
+   						double [][][][] dnn_feed = new double [num][][][];
+   						for (int j = 0; j < num; j++) {
+   							double [][][] f = splat ? splatField(dnn_roi[j], dnn_off[j], curt_save_select) : dnn_roi[j];
+   							if (rscale != 1.0) {
+   								double [][][] g = new double [f.length][][];
+   								for (int p = 0; p < f.length; p++) {
+   									g[p] = new double [f[p].length][];
+   									for (int su = 0; su < f[p].length; su++) { g[p][su] = f[p][su].clone(); for (int v = 0; v < g[p][su].length; v++) g[p][su][v] *= rscale; }
+   								}
+   								f = g;
+   							}
+   							dnn_feed[j] = f;
+   						}
+   						String rtitle = title_dnn + (splat ? "-SPLAT" : "");
+   						System.out.println(now()+" detectTargets(): DNN recurrent feed LEV"+nlev+(splat?" (offset-splat)":" (as-is)")+", scale "+rscale); // By Claude on 06/14/2026
+   						runRecurrentLevel(cuasRTUtils, dnn_feed, ts_dnn, curt_save_select, rtitle, false);
+   					}
    				}                                                                             // By Claude on 06/13/2026
    				dnn.close();                                                                  // By Claude on 06/13/2026
    			} catch (Exception e) {                                                           // By Claude on 06/13/2026