Changeset 13351 for trunk/psphot/src/pmFootprint.c

Timestamp:

May 11, 2007, 7:42:38 AM (19 years ago)

Author:

rhl

Message:

Implement and use pmGrowFootprintArray

File:

• trunk/psphot/src/pmFootprint.c (modified) (2 diffs)

trunk/psphot/src/pmFootprint.c

@@ -863 +863 @@
 /************************************************************************************************************/
 /*
+ * Grow a psArray of pmFootprints isotropically by r pixels, returning a new psArray of new pmFootprints
+ */
+psArray *pmGrowFootprintArray(const psArray *footprints, // footprints to grow
+                              int r) {  // how much to grow each footprint
+    assert (footprints->n == 0 || pmIsFootprint(footprints->data[0]));
+
+    if (footprints->n == 0) {           // we don't know the size of the footprint's region
+        return psArrayAlloc(0);
+    }
+    /*
+     * We'll insert the footprints into an image, then convolve with a disk,
+     * then extract a footprint from the result --- this is magically what we want.
+     */
+    psImage *idImage = pmSetFootprintArrayIDs(footprints, true);
+    if (r <= 0) {
+        r = 1;                          // r == 1 => no grow
+    }
+    psKernel *circle = psKernelAlloc(-r, r, -r, r);
+    assert (circle->image->numRows == 2*r + 1 && circle->image->numCols == circle->image->numRows);
+    for (int i = 0; i <= r; i++) {
+        for (int j = 0; j <= r; j++) {
+            if (i*i + j*j <= r*r) {
+                circle->kernel[i][j] = 
+                    circle->kernel[i][-j] = 
+                    circle->kernel[-i][j] = 
+                    circle->kernel[-i][-j] = 1;
+            }
+        }
+    }
+
+    psImage *grownIdImage = psImageConvolveDirect(idImage, circle);
+    psFree(circle);     
+
+    psArray *grown = pmFindFootprints(grownIdImage, 0.5, 1);
+    assert (grown != NULL);
+    psFree(idImage); psFree(grownIdImage);
+    /*
+     * Now assign the peaks appropriately.  We could do this more efficiently
+     * using idImage (which we just freed), but this is easy and probably fast enough
+     */
+    const psArray *peaks = pmFootprintArrayToPeaks(footprints);
+    pmPeaksAssignToFootprints(grown, peaks);
+    psFree((psArray *)peaks);
+
+    return grown;
+    
+}
+
+/************************************************************************************************************/
+/*
  * Merge together two psArrays of pmFootprints neither of which is damaged.
  *
@@ -911 +961 @@
     /*
      * Now assign the peaks appropriately.  We could do this more efficiently
-     * using idImage (which we just freed), but this is easy any probably fast enough
+     * using idImage (which we just freed), but this is easy and probably fast enough
      */
     const psArray *peaks;