fixed max for strictly negative data, fixes #1234

SyneRBI · Feb 19, 2024 · a323b88 · a323b88
1 parent f17f050
commit a323b88
Show file tree

Hide file tree

Showing 4 changed files with 23 additions and 10 deletions.
diff --git a/src/Registration/cReg/NiftiImageData.cpp b/src/Registration/cReg/NiftiImageData.cpp
@@ -1762,8 +1762,9 @@ void NiftiImageData<dataType>::sum(void* ptr) const
 template<class dataType>
 void NiftiImageData<dataType>::max(void* ptr) const
 {
-    float s = 0.0;
-    for (unsigned i = 0; i < this->_nifti_image->nvox; ++i) {
+    unsigned i = 0;
+    float s = _data[i++];
+    for (; i < this->_nifti_image->nvox; ++i) {
         float si = _data[i];
         if (si > s)
             s = si;

diff --git a/src/xGadgetron/cGadgetron/gadgetron_data_containers.cpp b/src/xGadgetron/cGadgetron/gadgetron_data_containers.cpp
@@ -566,12 +566,15 @@ MRAcquisitionData::max(const ISMRMRD::Acquisition& acq_a)
 {
     const complex_float_t* pa;
     complex_float_t z = 0;
+    bool init = true;
     for (pa = acq_a.data_begin(); pa != acq_a.data_end(); pa++) {
         complex_float_t zi = *pa;
         float r = std::real(z);
         float ri = std::real(zi);
-        if (ri > r)
+        if (init || ri > r) {
             z = zi;
+            init = false;
+        }
     }
     return z;
 }
@@ -626,6 +629,7 @@ MRAcquisitionData::max(void* ptr) const
     int n = number();
     complex_float_t z = 0;
     ISMRMRD::Acquisition a;
+    bool init = true;
     for (int i = 0; i < n;) {
         if (!get_acquisition(i, a)) {
             i++;
@@ -634,8 +638,10 @@ MRAcquisitionData::max(void* ptr) const
         complex_float_t zi = MRAcquisitionData::max(a);
         float r = std::real(z);
         float ri = std::real(zi);
-        if (ri > r)
+        if (init || ri > r) {
             z = zi;
+            init = false;
+        }
         i++;
     }
     complex_float_t* ptr_z = static_cast<complex_float_t*>(ptr);
@@ -1459,7 +1465,7 @@ GadgetronImageData::max(void* ptr) const
         complex_float_t zi = wi.max();
         float r = std::real(z);
         float ri = std::real(zi);
-        if (ri > r)
+        if (i == 0 || ri > r)
             z = zi;
     }
     complex_float_t* ptr_z = static_cast<complex_float_t*>(ptr);

diff --git a/src/xGadgetron/cGadgetron/include/sirf/Gadgetron/gadgetron_image_wrap.h b/src/xGadgetron/cGadgetron/include/sirf/Gadgetron/gadgetron_image_wrap.h
@@ -970,7 +970,7 @@ namespace sirf {
 				complex_float_t si = (complex_float_t)*i;
 				float r = std::real(*s);
 				float ri = std::real(si);
-				if (ri > r)
+				if (ii == 0 || ri > r)
 					*s = si;
 			}
 		}

diff --git a/src/xSTIR/cSTIR/stir_data_containers.cpp b/src/xSTIR/cSTIR/stir_data_containers.cpp
@@ -82,13 +82,19 @@ STIRAcquisitionData::max(void* ptr) const
 {
 	int n = get_max_segment_num();
 	float t = 0;
+	bool init = true;
         TOF_LOOP
 	for (int s = 0; s <= n; ++s)
 	{
 		SegmentBySinogram<float> seg = get_segment_by_sinogram(s TOF_ARG);
 		SegmentBySinogram<float>::full_iterator seg_iter;
 		for (seg_iter = seg.begin_all(); seg_iter != seg.end_all();)
-			t = std::max(t, *seg_iter++);
+			if (init) {
+				t = *seg_iter++;
+				init = false;
+			}
+			else
+				t = std::max(t, *seg_iter++);
 		if (s != 0) {
 			seg = get_segment_by_sinogram(-s TOF_ARG);
 			for (seg_iter = seg.begin_all(); seg_iter != seg.end_all();)
@@ -482,9 +488,9 @@ STIRImageData::max(void* ptr) const
 #else
 	typename Array<3, float>::const_full_iterator iter;
 #endif
-
-	float s = 0.0;
-	for (iter = data().begin_all(); iter != data().end_all(); iter++)
+	iter = data().begin_all();
+	float s = *iter++;
+	for (; iter != data().end_all(); iter++)
 		s = std::max(s, *iter);
 	float* ptr_s = static_cast<float*>(ptr);
 	*ptr_s = (float)s;