From 4084d18b163d350d7f8822509d246da51586c85f Mon Sep 17 00:00:00 2001
From: Erik Frojdh <erik.frojdh@psi.ch>
Date: Fri, 22 May 2026 17:01:53 +0200
Subject: [PATCH] reduced storage size

---
 include/aare/PixelHistogram.hpp    | 29 +++++++++++++++++------------
 python/src/bind_PixelHistogram.hpp |  6 +++---
 src/PixelHistogram.cpp             | 20 ++++++++++----------
 3 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/include/aare/PixelHistogram.hpp b/include/aare/PixelHistogram.hpp
index e6a9ea6..c54133a 100644
--- a/include/aare/PixelHistogram.hpp
+++ b/include/aare/PixelHistogram.hpp
@@ -8,21 +8,26 @@
 namespace bh = boost::histogram;
 
 namespace aare {
-class PixelHistogram{
+class PixelHistogram {
+  public:
+    using StorageType = uint16_t;
+    using AxisType = float;
+
+  private:
     using Axes = std::tuple<
-    bh::axis::regular<double, bh::use_default, bh::use_default, bh::axis::option::none_t>,
-    bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>,
-    bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>
-    >;
-    using Hist = bh::histogram<Axes, bh::dense_storage<int32_t>>;
+        bh::axis::regular<AxisType, bh::use_default, bh::use_default,
+                          bh::axis::option::none_t>,
+        bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>,
+        bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>>;
+    using Hist = bh::histogram<Axes, bh::dense_storage<StorageType>>;
     Hist hist_;
-    
-    public:
+
+  public:
     PixelHistogram(int rows, int cols, int n_bins, double xmin, double xmax);
-    void fill(const NDView<double,2>& image);
-    NDArray<int32_t,3> hdata() const;
-    NDArray<double,1> bin_centers() const;
-    NDArray<double,1> bin_edges() const;
+    void fill(const NDView<double, 2> &image);
+    NDArray<StorageType, 3> hdata() const;
+    NDArray<AxisType, 1> bin_centers() const;
+    NDArray<AxisType, 1> bin_edges() const;
 };
 
 } // namespace aare
diff --git a/python/src/bind_PixelHistogram.hpp b/python/src/bind_PixelHistogram.hpp
index e3e85aa..23ec6d1 100644
--- a/python/src/bind_PixelHistogram.hpp
+++ b/python/src/bind_PixelHistogram.hpp
@@ -43,7 +43,7 @@ void define_pixel_histogram_bindings(py::module &m) {
 
         .def("hdata",
              [](const PixelHistogram &self) {
-                 auto ptr = new NDArray<int32_t, 3>(self.hdata());
+                 auto ptr = new NDArray<PixelHistogram::StorageType, 3>(self.hdata());
                  return return_image_data(ptr);
              },
              R"(
@@ -55,7 +55,7 @@ void define_pixel_histogram_bindings(py::module &m) {
 
         .def("bin_centers",
              [](const PixelHistogram &self) {
-                 auto ptr = new NDArray<double, 1>(self.bin_centers());
+                 auto ptr = new NDArray<PixelHistogram::AxisType, 1>(self.bin_centers());
                  return return_image_data(ptr);
              },
              R"(
@@ -66,7 +66,7 @@ void define_pixel_histogram_bindings(py::module &m) {
              )")
         .def("bin_edges",
              [](const PixelHistogram &self) {
-                 auto ptr = new NDArray<double, 1>(self.bin_edges());
+                 auto ptr = new NDArray<PixelHistogram::AxisType, 1>(self.bin_edges());
                  return return_image_data(ptr);
              },
              R"(
diff --git a/src/PixelHistogram.cpp b/src/PixelHistogram.cpp
index bbc3de9..2d95b54 100644
--- a/src/PixelHistogram.cpp
+++ b/src/PixelHistogram.cpp
@@ -9,7 +9,7 @@ namespace aare {
 
 
 PixelHistogram::PixelHistogram(int rows, int cols, int n_bins, double xmin, double xmax): hist_(
-              bh::axis::regular<double, bh::use_default, bh::use_default,
+              bh::axis::regular<AxisType, bh::use_default, bh::use_default,
                                  bh::axis::option::none_t>(n_bins, xmin, xmax, "value"),
               bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>(0, cols, "y"),
               bh::axis::integer<int, bh::use_default, bh::axis::option::none_t>(0, rows, "x")
@@ -17,12 +17,12 @@ PixelHistogram::PixelHistogram(int rows, int cols, int n_bins, double xmin, doub
     // Constructor implementation
 }
 
-NDArray<int32_t,3> PixelHistogram::hdata() const {
+NDArray<PixelHistogram::StorageType, 3> PixelHistogram::hdata() const {
     const auto bins = static_cast<ssize_t>(hist_.axis(0).size());
     const auto cols = static_cast<ssize_t>(hist_.axis(1).size());
     const auto rows = static_cast<ssize_t>(hist_.axis(2).size());
 
-    NDArray<int32_t, 3> data({rows, cols, bins});
+    NDArray<StorageType, 3> data({rows, cols, bins});
 
     const auto &storage = bh::unsafe_access::storage(hist_);
     std::memcpy(data.data(), storage.data(), data.total_bytes());
@@ -38,27 +38,27 @@ void PixelHistogram::fill(const NDView<double, 2> &image) {
     }
 }
 
-NDArray<double, 1> PixelHistogram::bin_centers() const {
+NDArray<PixelHistogram::AxisType, 1> PixelHistogram::bin_centers() const {
     const auto& value_axis = hist_.axis(0);
     const auto n_bins = static_cast<ssize_t>(value_axis.size());
     
-    NDArray<double, 1> centers({n_bins});
+    NDArray<AxisType, 1> centers({n_bins});
     
     for (ssize_t i = 0; i < n_bins; ++i) {
         // Get the left and right edges of the bin and compute the center
-        double left = value_axis.value(i);
-        double right = value_axis.value(i + 1);
-        centers(i) = (left + right) / 2.0;
+        AxisType left = value_axis.value(i);
+        AxisType right = value_axis.value(i + 1);
+        centers(i) = (left + right) / AxisType(2.0);
     }
     
     return centers;
 }
 
-NDArray<double, 1> PixelHistogram::bin_edges() const {
+NDArray<PixelHistogram::AxisType, 1> PixelHistogram::bin_edges() const {
     const auto& value_axis = hist_.axis(0);
     const auto n_bins = static_cast<ssize_t>(value_axis.size());
 
-    NDArray<double, 1> edges({n_bins + 1});
+    NDArray<AxisType, 1> edges({n_bins + 1});
 
     for (ssize_t i = 0; i <= n_bins; ++i) {
         edges(i) = value_axis.value(i);