Changeset 42717

Timestamp:

Aug 14, 2024, 5:06:43 PM (2 years ago)

Author:

hgao

Message:

more robust normalization of the xReduced vector

File:

• branches/2dbias/psModules/src/detrend/pmOverscan.c (modified) (2 diffs)

branches/2dbias/psModules/src/detrend/pmOverscan.c

@@ -441 +441 @@
                 if (yscan->col0 >= xscan->col0 && yscan->col0 + yscan->numCols <= xscan->col0 + xscan->numCols)
                 {
-                        // define where to normalize the xReduced vector
-                        int j0 = yscan->col0 - xscan->col0 + (int)(yscan->numCols / 2) - 1;
+                        // define how to normalize the xReduced vector
+                        // slice the part overlapping withe yoverscan from xReduced
+                        long startIndex = yscan->col0 - xscan->col0;
+                        long normSize = xReduced->n - startIndex; // Calculate the size of the new vector
+                        // Allocate the new vector
+                        psVector *normVector = psVectorAlloc(normSize, PS_TYPE_F32);
+                        // Copy the data from xReduced starting from startIndex to the end
+                        for (long i = startIndex; i < xReduced->n; i++)
+                        {
+                                normVector->data.F32[i - startIndex] = xReduced->data.F32[i];
+                        }
+                        // Now normVector holds the sliced data; then, compute its robust mean
+                        psStatsOptions statistic = PS_STAT_CLIPPED_MEAN;
+                        psStats *stats = psStatsAlloc(statistic);
+                        if (!psVectorStats(stats, normVector, NULL, NULL, 0))
+                        {
+                                psError(PS_ERR_UNKNOWN, false, "failure to measure clipped mean as normalization of xReduced");
+                                psFree(stats);
+                                psFree(normVector);
+                                return NULL;
+                        }
+                        float xReducedNormalized = psStatsGetValue(stats, statistic);
+                        psFree(stats);
+                        psFree(normVector);
                         // XXX apply the 2D bias correction here
                         int yDiff = yscan->row0 - image->row0; // y offset between the science and the yoverscan region
@@ -452 +474 @@
                                         int iy = i + yDiff;
                                         int jx = j + xDiff;
-                                        image->data.F32[i][j] -= yReduced->data.F32[iy] - xReduced->data.F32[j0] + xReduced->data.F32[jx];
+                                        image->data.F32[i][j] -= yReduced->data.F32[iy] - xReducedNormalized + xReduced->data.F32[jx];
                                 }
                         }