testing image indexing

modules/python/bindings/include/core/arrays.hpp

@@ -96,7 +96,7 @@ void define_get_item_2d_array(PyClass &pyClass)
   pyClass.def("__getitem__", [](const Class &self, std::pair<int, int> pair) -> Item {
     int i = pair.first, j = pair.second;
     const int rows = (int)self.getRows(), cols = (int)self.getCols();
-    if (abs(i) > rows || abs(j) > cols) {
+    if (i >= rows || j >= cols || i < -rows || j < -cols) {
       std::stringstream ss;
       ss << "Invalid indexing into a 2D array: got indices " << shape_to_string({ i, j })
         << " but array has dimensions " << shape_to_string({ rows, cols });
@@ -112,7 +112,7 @@ void define_get_item_2d_array(PyClass &pyClass)
   });
   pyClass.def("__getitem__", [](const Class &self, int i) -> np_array_cf<Item> {
     const int rows = (int)self.getRows();
-    if (abs(i) > rows) {
+    if (i >= rows || i < -rows) {
       std::stringstream ss;
       ss << "Invalid indexing into a 2D array: got row index " << shape_to_string({ i })
         << " but array has " << rows << " rows";

modules/python/bindings/include/core/images.hpp

@@ -57,7 +57,7 @@ void define_get_item_2d_image(py::class_<vpImage<T>> &pyClass)
   pyClass.def("__getitem__", [](const vpImage<T> &self, std::pair<int, int> pair) -> T {
     int i = pair.first, j = pair.second;
     const int rows = (int)self.getHeight(), cols = (int)self.getRows();
-    if (abs(i) > rows || abs(j) > cols) {
+    if (i >= rows || j >= cols || i < -rows || j < -cols) {
       std::stringstream ss;
       ss << "Invalid indexing into a 2D image: got indices " << shape_to_string({ i, j })
         << " but image has dimensions " << shape_to_string({ rows, cols });
@@ -73,7 +73,7 @@ void define_get_item_2d_image(py::class_<vpImage<T>> &pyClass)
   });
   pyClass.def("__getitem__", [](const vpImage<T> &self, int i) -> np_array_cf<NpRep> {
     const int rows = (int)self.getRows();
-    if (abs(i) > rows) {
+    if (i >= rows || i < -rows) {
       std::stringstream ss;
       ss << "Invalid indexing into a 2D image: got row index " << shape_to_string({ i })
         << " but array has " << rows << " rows";

modules/python/test/test_numpy_image.py

@@ -0,0 +1,116 @@
+#############################################################################
+#
+# ViSP, open source Visual Servoing Platform software.
+# Copyright (C) 2005 - 2023 by Inria. All rights reserved.
+#
+# This software is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# See the file LICENSE.txt at the root directory of this source
+# distribution for additional information about the GNU GPL.
+#
+# For using ViSP with software that can not be combined with the GNU
+# GPL, please contact Inria about acquiring a ViSP Professional
+# Edition License.
+#
+# See https://visp.inria.fr for more information.
+#
+# This software was developed at:
+# Inria Rennes - Bretagne Atlantique
+# Campus Universitaire de Beaulieu
+# 35042 Rennes Cedex
+# France
+#
+# If you have questions regarding the use of this file, please contact
+# Inria at [email protected]
+#
+# This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+# WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Description:
+# ViSP Python bindings test
+#
+#############################################################################
+
+from typing import Any, List, Dict
+from visp.core import ImageGray, ImageRGBA, ImageRGBf, RGBa, RGBf
+
+import numpy as np
+import pytest
+
+def get_data_dicts() -> List[Dict[str, Any]]:
+  h, w = 20, 20
+  return [
+    {
+      'instance': ImageGray(h, w, 0),
+      'base_value': 0,
+      'value': 255,
+      'np_value': 255,
+      'shape': (h, w),
+      'dtype': np.uint8
+    },
+    {
+      'instance': ImageRGBA(h, w, RGBa(0, 50, 75, 255)),
+      'base_value': RGBa(0, 50, 75, 255),
+      'value': RGBa(255, 128, 0, 100),
+      'np_value': np.asarray([255, 128, 0, 100], dtype=np.uint8),
+      'shape': (h, w, 4),
+      'dtype': np.uint8
+    },
+    {
+      'instance': ImageRGBf(h, w, RGBf(0.0, 0.0, 0.0)),
+      'base_value': RGBf(0.0, 0.0, 0.0),
+      'value': RGBf(255, 0, 0),
+      'np_value': np.asarray([255, 0, 0], dtype=np.float32),
+      'shape': (h, w, 3),
+      'dtype': np.float32
+
+    },
+
+  ]
+
+
+def test_np_array_shape_type():
+  '''
+  Tests buffer definition, shape and dtype
+  '''
+  for test_dict in get_data_dicts():
+    np_array = np.array(test_dict['instance'], copy=False)
+    assert np_array.shape == test_dict['shape']
+    assert np_array.dtype == test_dict['dtype']
+
+def test_np_array_shape_type_numpy_fn():
+  '''
+  Tests converting to a numpy array by calling our defined function
+  '''
+  for test_dict in get_data_dicts():
+    np_array = test_dict['instance'].numpy()
+    assert np_array.shape == test_dict['shape']
+    assert np_array.dtype == test_dict['dtype']
+
+def test_np_array_replace_value():
+  '''
+  Tests 2D pixel indexing and correspondance between visp pixel reps and numpy reps
+  '''
+  for test_dict in get_data_dicts():
+    vp_image = test_dict['instance']
+    np_array = np.array(vp_image, copy=False)
+    np_array[::2, ::2] = test_dict['np_value']
+    for i in range(vp_image.getHeight()):
+      for j in range(vp_image.getWidth()):
+        if i % 2 == 0 and j % 2 == 0:
+          assert vp_image[i, j] == test_dict['value']
+          assert vp_image[-i, -j] == test_dict['value']
+        else:
+          assert vp_image[i, j] == test_dict['base_value']
+          assert vp_image[-i, -j] == test_dict['base_value']
+
+    with pytest.raises(RuntimeError):
+      vp_image[vp_image.getHeight()]
+    with pytest.raises(RuntimeError):
+      vp_image[0, vp_image.getWidth()]
+    with pytest.raises(RuntimeError):
+      vp_image[-vp_image.getHeight() - 1]
+    with pytest.raises(RuntimeError):
+      vp_image[0, -vp_image.getWidth() - 1]