TestFrameInterpolatorBilinear.h

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/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
 
#ifndef META_OCEAN_TEST_TESTCV_TEST_FRAME_INTERPOLATOR_BILINEAR_H
#define META_OCEAN_TEST_TESTCV_TEST_FRAME_INTERPOLATOR_BILINEAR_H
 
#include "ocean/test/testcv/TestCV.h"
 
#include "ocean/base/Frame.h"
#include "ocean/base/Worker.h"
 
#include "ocean/cv/PixelPosition.h"
 
#include "ocean/math/Lookup2.h"
#include "ocean/math/SquareMatrix3.h"
#include "ocean/math/Vector2.h"
 
#include "ocean/test/TestSelector.h"
 
namespace Ocean
{
 
namespace Test
{
 
namespace TestCV
{
 
/**
 * This class implements a bilinear frame interpolation test.
 * @ingroup testcv
 */
class OCEAN_TEST_CV_EXPORT TestFrameInterpolatorBilinear
{
    public:
 
        /**
         * Tests all bilinear interpolation filter functions.
         * @param width The width of the source frame in pixel
         * @param height The height of the source frame in pixel
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @param selector The test selector to control which tests to run
         * @return True, if succeeded
         */
        static bool test(const unsigned int width, const unsigned int height, const double testDuration, Worker& worker, const TestSelector& selector = TestSelector());
 
        /**
         * Tests the pixel interpolation function for frames with 8 bit per channel.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testInterpolatePixel8BitPerChannel(const double testDuration);
 
        /**
         * Tests the pixel interpolation function for frames with 8 bit per channel.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param pixelCenter The pixel center to be used
         * @return True, if succeeded
         * @tparam TScalar The data type of the scalar to be used, either 'float' or 'double'
         */
        template <typename TScalar>
        static bool testInterpolatePixel8BitPerChannel(const CV::PixelCenter pixelCenter, const double testDuration);
 
        /**
         * Tests the pixel interpolation function for frames with arbitrary data type.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testInterpolatePixel(const double testDuration);
 
        /**
         * Tests the pixel interpolation function for frames arbitrary data type.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param pixelCenter The pixel center to be used
         * @return True, if succeeded
         * @tparam TSource The data type of the source to be used
         * @tparam TTarget The data type of the target to be used
         * @tparam TScalar The data type of the scalar to be used, either 'float' or 'double'
         */
        template <typename TSource, typename TTarget, typename TScalar>
        static bool testInterpolatePixel(const CV::PixelCenter pixelCenter, const double testDuration);
 
        /**
         * Tests the affine transformation function using a constant color for unknown image content.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testAffine(const double testDuration, Worker& worker);
 
        /**
         * Tests the homography transformation function supporting arbitrary pixel formats using a constant color for unknown image content.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool testHomography(const double testDuration, Worker& worker);
 
        /**
         * Tests the homography transformation function defining a binary mask for known and unknown image content.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testHomographyMask(const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear resize function for extreme image resolutions.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testResizeExtremeResolutions(const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear resize function.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testResize(const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear resize function supporting arbitrary data types.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., `uint8_t`, 'float', 'double', ...
         */
        template <typename T>
        static bool testResize(const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear scale function with scale factors which are not derived from the frame dimensions.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testScale(const double testDuration, Worker& worker);
 
        /**
         * Tests the frame transformation function applying a lookup table.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testLookup(const double testDuration, Worker& worker);
 
        /**
         * Tests the frame transformation function applying a lookup table.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., `uint8_t`, 'float', 'double', ...
         */
        template <typename T>
        static bool testLookup(const double testDuration, Worker& worker);
 
        /**
         * Tests the frame mask transformation function applying a lookup table.
         * @param width The width of the test frame in pixel, with range [1, infinity)
         * @param height The height of the test frame in pixel, with range [1, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testLookupMask(const unsigned int width, const unsigned int height, const double testDuration, Worker& worker);
 
        /**
         * Tests the frame rotate function.
         * @param width The width of the test frame in pixel, with range [1, infinity)
         * @param height The height of the test frame in pixel, with range [1, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testRotateFrame(const unsigned int width, const unsigned int height, const double testDuration, Worker& worker);
 
        /**
         * Tests the intensity sum of an image patch with sub-pixel location in a 1-channel frame using an integral image.
         * @param width The width of the frame in pixel, with range [64, infinity)
         * @param height The height of the frame in pixel, with range [64, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testPatchIntensitySum1Channel(const unsigned int width, const unsigned int height, const double testDuration);
 
        /**
         * Tests the function for affine transformations (with constant color for unknown image content) for a given frame dimension and channel number.
         * @param width The width of the frame in pixel, with range [1, infinity)
         * @param height The height of the frame in pixel, with range [1, infinity)
         * @param channels The number of frame channels, with range [1, 4]
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testAffine(const unsigned int width, const unsigned int height, const unsigned int channels, const double testDuration, Worker& worker);
 
        /**
         * Tests the homography transformation function (with constant color for unknown image content) for arbitrary data types and for a given frame dimension and channel number.
         * @param width The width of the frame in pixel, with range [1, infinity)
         * @param height The height of the frame in pixel, with range [1, infinity)
         * @param channels The number of frame channels, with range [1, 4]
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool testHomography(const unsigned int width, const unsigned int height, const unsigned int channels, const double testDuration, Worker& worker);
 
        /**
         * Tests the homography transformation function (with binary mask defining known and unknown image content) for a given frame dimension and channel number.
         * @param width The width of the frame in pixel, with range [1, infinity)
         * @param height The height of the frame in pixel, with range [1, infinity)
         * @param channels The number of frame channels, with range [1, 4]
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testHomographyMask(const unsigned int width, const unsigned int height, const unsigned int channels, const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear resize function for a given frame dimension and channel number.
         * @param sourceWidth Width of the source frame in pixel
         * @param sourceHeight Height of the source frame in pixel
         * @param sourceChannels Number of the data channels of the source frame, with range [1, 4]
         * @param targetWidth Width of the target frame in pixel
         * @param targetHeight Height of the target frame in pixel
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testResize(const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int sourceChannels, const unsigned int targetWidth, const unsigned int targetHeight, const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear resize function for arbitrary data types and for a given frame dimension and channel number.
         * @param sourceWidth Width of the source frame in pixel
         * @param sourceHeight Height of the source frame in pixel
         * @param sourceChannels Number of the data channels of the source frame
         * @param targetWidth Width of the target frame in pixel
         * @param targetHeight Height of the target frame in pixel
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool testResize(const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int sourceChannels, const unsigned int targetWidth, const unsigned int targetHeight, const double testDuration, Worker& worker);
 
        /**
         * Tests the bilinear scale function for a given frame dimension, channel number, and pair of scale factors.
         * @param sourceWidth Width of the source frame in pixel
         * @param sourceHeight Height of the source frame in pixel
         * @param channels Number of the data channels of the source frame, with range [1, 4]
         * @param targetWidth Width of the target frame in pixel
         * @param targetHeight Height of the target frame in pixel
         * @param xSource_s_xTarget The horizontal scale factor converting a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param ySource_s_yTarget The vertical scale factor converting a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testScale(const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int channels, const unsigned int targetWidth, const unsigned int targetHeight, const double xSource_s_xTarget, const double ySource_s_yTarget, const double testDuration, Worker& worker);
 
        /**
         * Tests the special case resize function for image resolutions from 400x400 to 256x256.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testSpecialCasesResize400x400To256x256_8BitPerChannel(const double testDuration);
 
        /**
         * Tests the special case resize function for image resolutions from 400x400 to 224x224.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testSpecialCasesResize400x400To224x224_8BitPerChannel(const double testDuration);
 
        /**
         * Tests the frame transformation function applying a lookup table.
         * @param width The width of the test frame in pixel, with range [20, infinity)
         * @param height The height of the test frame in pixel, with range [20, infinity)
         * @param channels The number of frame channels, with range [1, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool testLookup(const unsigned int width, const unsigned int height, const unsigned int channels, const double testDuration, Worker& worker);
 
        /**
         * Tests the function to re-sample a camera image.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         */
        static bool testResampleCameraImage(const double testDuration, Worker& worker);
 
        /**
         * Tests the function to re-sample a camera image.
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @param worker The worker object to distribute the CPU load
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool testResampleCameraImage(const double testDuration, Worker& worker);
 
        /**
         * Validates the bilinear frame resize function.
         * @param source The source frame that has been resized, must be valid
         * @param sourceWidth The width of the source frame in pixel, with range [1, infinity)
         * @param sourceHeight The height of the source frame in pixel, with range [1, infinity)
         * @param channels Number of the data channels of the source (and target) frame, with range [1, 4]
         * @param target The resized target frame to be verified, must be valid
         * @param targetWidth The width of the target frame in pixel, with range [1, infinity)
         * @param targetHeight The height of the target frame in pixel, with range [1, infinity)
         * @param xTargetToSource The horizontal scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param yTargetToSource The vertical scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param sourcePaddingElements Optional padding at the end of each source row in elements, with range [0, infinity)
         * @param targetPaddingElements Optional padding at the end of each target row in elements, with range [0, infinity)
         * @param averageAbsErrorToInteger Optional resulting average absolute error between the converted result and the ground truth integer result (rounded result), with range [0, 256)
         * @param maximalAbsErrorToInteger Optional resulting maximal absolute error between the converted result and the ground truth integer result (rounded result), with range [0, 256)
         * @param groundTruth Optional resulting ground truth data (the resized image content determined with floating point accuracy), nullptr otherwise
         */
        static void validateScaleFrame(const unsigned char* source, const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int channels, const unsigned char* target, const unsigned int targetWidth, const unsigned int targetHeight, const double xTargetToSource, const double yTargetToSource, const unsigned int sourcePaddingElements, const unsigned int targetPaddingElements, double* averageAbsErrorToInteger, unsigned int* maximalAbsErrorToInteger, unsigned char* groundTruth = nullptr);
 
        /**
         * Validates the bilinear frame resize function for arbitrary data types.
         * @param source The source frame that has been resized, must be valid
         * @param sourceWidth The width of the source frame in pixel, with range [1, infinity)
         * @param sourceHeight The height of the source frame in pixel, with range [1, infinity)
         * @param channels Number of the data channels of the source (and target) frame, with range [1, 4]
         * @param target The resized target frame to be verified, must be valid
         * @param targetWidth The width of the target frame in pixel, with range [1, infinity)
         * @param targetHeight The height of the target frame in pixel, with range [1, infinity)
         * @param xSource_s_xTarget The horizontal scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param ySource_s_yTarget The vertical scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param sourcePaddingElements Optional padding at the end of each source row in elements, with range [0, infinity)
         * @param targetPaddingElements Optional padding at the end of each target row in elements, with range [0, infinity)
         * @param averageAbsError Optional resulting average absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param maximalAbsError Optional resulting maximal absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param groundTruth Optional resulting ground truth data (the resized image content determined with floating point accuracy), nullptr otherwise
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static void validateScaleFrame(const T* source, const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int channels, const T* target, const unsigned int targetWidth, const unsigned int targetHeight, const double xSource_s_xTarget, const double ySource_s_yTarget, const unsigned int sourcePaddingElements, const unsigned int targetPaddingElements, double* averageAbsError, double* maximalAbsError, T* groundTruth = nullptr);
 
        /**
         * Validates the homography interpolation function for (almost) arbitrary pixel formats (using a constant background color for unknown image content).
         * @param input The input frame which has been used for the interpolation, must be valid
         * @param output The output frame holding the interpolated image information of the input frame, must be valid
         * @param input_H_output The homography that has been used to interpolate/warp the frame, transforming points int he output frame to points in the input frame, must not be singular
         * @param backgroundColor The background color for all pixels for which no valid source pixel exists, one for each frame channel, must be valid
         * @param interpolatedFrameOrigin The origin of the interpolated frame defining the global position of the interpolated frame's pixel coordinate (0, 0), with range (-infinity, infinity)x(-infinity, infinity)
         * @param averageAbsError Optional resulting average absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param maximalAbsError Optional resulting maximal absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param groundTruth Optional resulting ground truth frame (the resized image content determined with floating point accuracy), nullptr if not of interest
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static void validateHomography(const Frame& input, const Frame& output, const SquareMatrix3& input_H_output, const T* backgroundColor, const CV::PixelPositionI& interpolatedFrameOrigin, double* averageAbsError, double* maximalAbsError, Frame* groundTruth = nullptr);
 
    protected:
 
        /**
         * Tests the intensity sum of an image patch with sub-pixel location in a 1-channel frame using an integral image.
         * @param width The width of the frame, in pixel, with range [patchWidth + 1u, infinity)
         * @param height The height of the frame, in pixel, with range [patchHeight + 1u, infinity)
         * @param patchWidth Width of the patch, in pixel, with range [1, infinity)
         * @param patchHeight Height of the patch, in pixel, with range [1, infinity)
         * @param testDuration Number of seconds for each test, with range (0, infinity)
         * @return True, if succeeded
         */
        static bool testPatchIntensitySum1Channel(const unsigned int width, const unsigned int height, const unsigned int patchWidth, const unsigned int patchHeight, const double testDuration);
 
        /**
         * Validates a pixel interpolation result for frame with 8 bit per channel.
         * @param frame The frame in pixel the pixel interpolation was applied, must be valid
         * @param position The position for which the interpolated pixel will be determined, with ranges [0, frame.width() - 1]x[0, frame.height() - 1] for PC_TOP_LEFT, [0, frame.width()]x[0, frame.height()] for PC_CENTER
         * @param pixelCenter The pixel center to be used during interpolation
         * @param interpolationResult The interpolation result to be verified, one for each frame channel
         * @param threshold The maximal distance between interpolated result and ground-truth result so that the result is valid, with range [0, 255)
         * @return True, if the interpolation is correct
         * @tparam TScalar The data type of a scalar, either 'float' or 'double'
         */
        template <typename TScalar>
        static bool validateInterpolatePixel8BitPerChannel(const Frame& frame, const VectorT2<TScalar>& position, const CV::PixelCenter pixelCenter, const uint8_t* const interpolationResult, const TScalar threshold);
 
        /**
         * Validates a pixel interpolation result for frame with arbitrary data type.
         * @param frame The frame in pixel the pixel interpolation was applied, must be valid
         * @param position The position for which the interpolated pixel will be determined, with ranges [0, frame.width() - 1]x[0, frame.height() - 1] for PC_TOP_LEFT, [0, frame.width()]x[0, frame.height()] for PC_CENTER
         * @param pixelCenter The pixel center to be used during interpolation
         * @param interpolationResult The interpolation result to be verified, one for each frame channel
         * @param threshold The maximal distance between interpolated result and ground-truth result so that the result is valid, with range [0, 255)
         * @return True, if the interpolation is correct
         * @tparam TSource The data type of the source to be used
         * @tparam TTarget The data type of the target to be used
         * @tparam TScalar The data type of a scalar, either 'float' or 'double'
         */
        template <typename TSource, typename TTarget, typename TScalar>
        static bool validateInterpolatePixel(const Frame& frame, const VectorT2<TScalar>& position, const CV::PixelCenter pixelCenter, const TTarget* const interpolationResult, const TScalar threshold);
 
        /**
         * Validation function for the bilinear interpolation of 2D homogeneous image transformations (+ constant background color for unknown image content).
         * @param source The frame which will be interpolated based on the homography, must be valid
         * @param validationTarget The interpolated frame that will be validated, must the same pixel format and origin as 'source' and must be valid
         * @param source_H_target The 2D homogeneous image transformation that has been used to interpolate/warp the frame, transforming points defined in the interpolatedFrame to the source frame, i.e. pointFrame = transformation * pointInterpolatedFrame, must not be singular
         * @param backgroundColor The background color for all pixels for which no valid source pixel exists, one for each frame channel, must be valid
         * @param interpolatedFrameOrigin The origin of the interpolated frame defining the global position of the interpolated frame's pixel coordinate (0, 0), with range (-infinity, infinity)x(-infinity, infinity)
         * @return True, if the interpolation is correct
         */
        static bool validateTransformation8BitPerChannel(const Frame& source, const Frame& validationTarget, const SquareMatrix3& source_H_target, const uint8_t* backgroundColor, const CV::PixelPositionI& interpolatedFrameOrigin);
 
        /**
         * Validates the homography interpolation function (using a binary mask to define known and unknown image content).
         * @param frame The frame which will be interpolated based on the homography, must be valid
         * @param interpolatedFrame The interpolated/warped frame to be validated, width same pixel format and pixel origin as 'frame, must be valid
         * @param interpolatedMask The binary mask corresponding to the interpolated/warped frame specifying known and unknown image content, a mask value of 0xFF defined known image content, 0x00 defines unknown image content, with same pixel origin and frame resolution as 'interpolatedFrame'
         * @param input_H_output The homography that has been used to interpolate/warp the frame, transforming points in the output frame to points in the input frame, must not be singular
         * @param interpolatedFrameOrigin The origin of the interpolated frame defining the global position of the interpolated frame's pixel coordinate (0, 0), with range (-infinity, infinity)x(-infinity, infinity)
         * @return True, if the interpolation is correct
         */
        static bool validateHomographyMask8BitPerChannel(const Frame& frame, const Frame& interpolatedFrame, const Frame& interpolatedMask, const SquareMatrix3& input_H_output, const CV::PixelPositionI& interpolatedFrameOrigin);
 
        /**
         * Validates the frame transformation function applying a lookup table.
         * @param sourceFrame The source frame which has been transformed, must be valid
         * @param targetFrame The target frame which holds the transformed input frame, must be valid
         * @param lookupTable The lookup table which has been used for the transformation, must be valid
         * @param offset True, to interpret the lookup values as offset values; False, to interpret the lookup values as absolute locations
         * @param backgroundColor The background color to be used, must be valid
         * @return True, if succeeded
         * @tparam T The data type of each pixel channel, e.g., 'float', 'double', 'int', ...
         */
        template <typename T>
        static bool validateLookup(const Frame& sourceFrame, const Frame& targetFrame, const LookupCorner2<Vector2>& lookupTable, const bool offset, const T* backgroundColor);
 
        /**
         * Validates the frame mask transformation function applying a lookup table.
         * @param sourceFrame The source frame which has been transformed, must be valid
         * @param targetFrame The target frame which holds the transformed input frame, must be valid
         * @param targetMask The mask associated with the target frame, must be valid
         * @param lookupTable The lookup table which has been used for the transformation, must be valid
         * @param offset True, to interpret the lookup values as offset values; False, to interpret the lookup values as absolute locations
         * @return True, if succeeded
         */
        static bool validateLookupMask(const Frame& sourceFrame, const Frame& targetFrame, const Frame& targetMask, const LookupCorner2<Vector2>& lookupTable, const bool offset);
 
        /**
         * Validates the rotation of a frame using a bilinear interpolation.
         * @param source The source frame to be rotated, must be valid
         * @param target The target frame which will receive the rotated image, with same frame type as the source frame, must be valid
         * @param anchorX Position of the rotation anchor in the horizontal direction, with range (-infinity, infinity)
         * @param anchorY Position of the rotation anchor in the vertical direction, with range (-infinity, infinity)
         * @param angle The counter clockwise rotation angle in radian, with range [0, 2PI)
         */
        static bool validateRotatedFrame(const Frame& source, const Frame& target, const Scalar anchorX, const Scalar anchorY, const Scalar angle);
 
        /**
         * Validate the intensity sum of an image patch with sub-pixel location in a 1-channel frame.
         * @param yFrame The frame in which the intensity sum is determined, with pixel format FORMAT_Y8, must be valid
         * @param patchWidth The width of the patch, in pixel, with range [1, infinity)
         * @param patchHeight The height of the patch, in pixel, with range [1, infinity)
         * @param center The center of the image patch to be used
         * @param pixelCenter The pixel center to be used
         * @param intensity The intensity sum to verify
         * @return True, if succeeded
         */
        static bool validatePatchIntensitySum1Channel(const Frame& yFrame, const unsigned int patchWidth, const unsigned int patchHeight, const Vector2& center, const CV::PixelCenter pixelCenter, const Scalar intensity);
 
        /**
         * Validate the bilinear extraction of frame patches
         * @param source Pointer to the data of the source frame, must be valid
         * @param validationTarget Pointer to the data of the target frame that will validated, must be valid
         * @param sourceWidth Width of the source frame in pixels, range: [targetWidth, infinity)
         * @param sourceHeight Height of the source frame in pixels, range: [targetWidth, infinity)
         * @param x Horizontal center position of the patch, range: [targetWidth/2, sourceWidth - targetWidth/2)
         * @param y Vertical center position of the patch, range: [targetHeight/2, sourceHeight - targetHeight/2)
         * @param validationTargetWidth Width of the target frame, range: all odd values in range [1, sourceWidth]
         * @param validationTargetHeight Height of the target frame, range: all odd values in range [1, sourceHeight]
         * @param sourcePaddingElements Optional number of padding elements of the source frame
         * @param validationTargetPaddingElements Optional number of padding elements of the target frame
         * @return True if the validation was successful, otherwise false.
         * @tparam tChannels Number of data channels of the given source frame, range: [1, infinity)
         */
        template <uint32_t tChannels>
        static bool validatePatchFrame8BitPerChannel(const uint8_t* const source, const uint8_t* const validationTarget, const uint32_t sourceWidth, const uint32_t sourceHeight, const Scalar x, const Scalar y, const uint32_t validationTargetWidth, const uint32_t validationTargetHeight, const uint32_t sourcePaddingElements, const uint32_t validationTargetPaddingElements);
 
        /**
         * Validates the bilinear frame resize function for uint8_t data types using 7-bit integer precision.
         * This function first interpolates two rows and stores the interpolated result as uint8_t values, followed by an interpolation within the row.
         * @param source The source frame that has been resized, must be valid
         * @param sourceWidth The width of the source frame in pixel, with range [1, infinity)
         * @param sourceHeight The height of the source frame in pixel, with range [1, infinity)
         * @param channels Number of the data channels of the source (and target) frame, with range [1, 4]
         * @param target The resized target frame to be verified, must be valid
         * @param targetWidth The width of the target frame in pixel, with range [1, infinity)
         * @param targetHeight The height of the target frame in pixel, with range [1, infinity)
         * @param xSource_s_xTarget The horizontal scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param ySource_s_yTarget The vertical scale factor transforming a location in the target frame to a location in the source frame, with range (0, infinity)
         * @param sourcePaddingElements Optional padding at the end of each source row in elements, with range [0, infinity)
         * @param targetPaddingElements Optional padding at the end of each target row in elements, with range [0, infinity)
         * @param averageAbsError Optional resulting average absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param maximalAbsError Optional resulting maximal absolute error between the converted result and the ground truth result, with range (-infinity, infinity)
         * @param groundTruth Optional resulting ground truth data (the resized image content determined with floating point accuracy), nullptr otherwise
         */
        static void validateScaleFramePrecision7Bit(const uint8_t* source, const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int channels, const uint8_t* target, const unsigned int targetWidth, const unsigned int targetHeight, const double xSource_s_xTarget, const double ySource_s_yTarget, const unsigned int sourcePaddingElements, const unsigned int targetPaddingElements, double* averageAbsError, double* maximalAbsError, uint8_t* groundTruth = nullptr);
};
 
template <typename T>
void TestFrameInterpolatorBilinear::validateScaleFrame(const T* source, const unsigned int sourceWidth, const unsigned int sourceHeight, const unsigned int channels, const T* target, const unsigned int targetWidth, const unsigned int targetHeight, const double xSource_s_xTarget, const double ySource_s_yTarget, const unsigned int sourcePaddingElements, const unsigned int targetPaddingElements, double* averageAbsError, double* maximalAbsError, T* groundTruth)
{
    ocean_assert(source != nullptr && target != nullptr);
    ocean_assert(sourceWidth != 0u && sourceHeight != 0u);
    ocean_assert(targetWidth != 0u && targetHeight != 0u);
    ocean_assert(channels >= 1u);
    ocean_assert(xSource_s_xTarget > 0.0 && ySource_s_yTarget > 0.0);
 
    const unsigned int sourceStrideElements = sourceWidth * channels + sourcePaddingElements;
    const unsigned int targetStrideElements = targetWidth * channels + targetPaddingElements;
 
    std::vector<T> result(channels, T(0));
 
    if (averageAbsError)
    {
        *averageAbsError = NumericD::maxValue();
    }
 
    if (maximalAbsError)
    {
        *maximalAbsError = NumericD::maxValue();
    }
 
    double sumAbsError = 0.0;
    double maxAbsError = 0.0;
 
    for (unsigned int y = 0u; y < targetHeight; ++y)
    {
        for (unsigned int x = 0u; x < targetWidth; ++x)
        {
            const double sx = minmax(0.0, (double(x) + 0.5) * xSource_s_xTarget - 0.5, double(sourceWidth - 1u));
            const double sy = minmax(0.0, (double(y) + 0.5) * ySource_s_yTarget - 0.5, double(sourceHeight - 1u));
 
            const unsigned int leftPixel = (unsigned int)sx;
            const unsigned int rightPixel = min(leftPixel + 1u, sourceWidth - 1u);
            ocean_assert(leftPixel < sourceWidth && rightPixel < sourceWidth);
 
            const unsigned int topPixel = (unsigned int)sy;
            const unsigned int bottomPixel = min(topPixel + 1u, sourceHeight - 1u);
            ocean_assert(topPixel < sourceHeight && bottomPixel < sourceHeight);
 
            const double rightFactor = sx - double(leftPixel);
            const double bottomFactor = sy - double(topPixel);
 
            ocean_assert(rightFactor >= 0.0 && rightFactor <= 1.0);
            ocean_assert(bottomFactor >= 0.0 && bottomFactor <= 1.0);
 
            const double leftFactor = 1.0 - rightFactor;
            const double topFactor = 1.0 - bottomFactor;
 
            const T* sourceTopLeft = source + sourceStrideElements * topPixel + leftPixel * channels;
            const T* sourceTopRight = source + sourceStrideElements * topPixel + rightPixel * channels;
 
            const T* sourceBottomLeft = source + sourceStrideElements * bottomPixel + leftPixel * channels;
            const T* sourceBottomRight = source + sourceStrideElements * bottomPixel + rightPixel * channels;
 
            for (unsigned int n = 0u; n < channels; ++n)
            {
                const double top = double(sourceTopLeft[n]) * leftFactor + double(sourceTopRight[n]) * rightFactor;
                const double bottom = double(sourceBottomLeft[n]) * leftFactor + double(sourceBottomRight[n]) * rightFactor;
 
                const double interpolated = top * topFactor + bottom * bottomFactor;
 
                result[n] = T(interpolated);
            }
 
            const T* const targetValue = target + targetStrideElements * y + x * channels;
 
            for (unsigned int n = 0u; n < channels; ++n)
            {
                const double absError = NumericD::abs(double(result[n]) - double(targetValue[n]));
 
                sumAbsError += absError;
                maxAbsError = max(maxAbsError, absError);
            }
 
            if (groundTruth)
            {
                memcpy(groundTruth + (y * targetWidth + x) * channels, result.data(), sizeof(T) * channels);
            }
        }
    }
 
    if (averageAbsError)
    {
        *averageAbsError = sumAbsError / double(targetWidth * targetHeight * channels);
    }
 
    if (maximalAbsError)
    {
        *maximalAbsError = maxAbsError;
    }
}
 
template <typename T>
void TestFrameInterpolatorBilinear::validateHomography(const Frame& input, const Frame& output, const SquareMatrix3& input_H_output, const T* backgroundColor, const CV::PixelPositionI& interpolatedFrameOrigin, double* averageAbsError, double* maximalAbsError, Frame* groundTruth)
{
    ocean_assert(input.isValid() && output.isValid());
    ocean_assert(input.isPixelFormatCompatible(output.pixelFormat()));
 
    ocean_assert(!input_H_output.isSingular());
    ocean_assert(backgroundColor != nullptr);
 
    const Scalar frameBorderEps = Scalar(0.5);
 
    ocean_assert(input.numberPlanes() == 1u);
 
    const unsigned int channels = input.channels();
    ocean_assert(channels >= 1u);
 
    std::vector<T> result(channels, T(0));
 
    if (averageAbsError != nullptr)
    {
        *averageAbsError = NumericD::maxValue();
    }
 
    if (maximalAbsError != nullptr)
    {
        *maximalAbsError = NumericD::maxValue();
    }
 
    if (groundTruth != nullptr)
    {
        groundTruth->set(output.frameType(), false /*forceOwner*/, true /*forceWritable*/);
    }
 
    double sumAbsError = 0.0;
    double maxAbsError = 0.0;
    unsigned long long measurements = 0ull;
 
    for (unsigned int yOutput = 0u; yOutput < output.height(); ++yOutput)
    {
        for (unsigned int xOutput = 0u; xOutput < output.width(); ++xOutput)
        {
            const T* const outputPixel = output.constpixel<T>(xOutput, yOutput);
 
            const Vector2 outputPosition = Vector2(Scalar(xOutput) + Scalar(interpolatedFrameOrigin.x()), Scalar(yOutput) + Scalar(interpolatedFrameOrigin.y()));
            const Vector2 inputPosition = input_H_output * outputPosition;
 
            if (inputPosition.x() >= Scalar(0) && inputPosition.y() >= Scalar(0) && inputPosition.x() <= Scalar(input.width() - 1u) && inputPosition.y() <= Scalar(input.height() - 1u))
            {
                const unsigned int inputLeftPixel = (unsigned int)(inputPosition.x());
                const unsigned int inputRightPixel = min(inputLeftPixel + 1u, input.width() - 1u);
 
                const unsigned int inputTopPixel = (unsigned int)(inputPosition.y());
                const unsigned int inputBottomPixel = min(inputTopPixel + 1u, input.height() - 1u);
 
                const double rightFactor = double(inputPosition.x()) - double(inputLeftPixel);
                const double bottomFactor = double(inputPosition.y()) - double(inputTopPixel);
 
                ocean_assert(rightFactor >= 0.0 && rightFactor <= 1.0);
                ocean_assert(bottomFactor >= 0.0 && bottomFactor <= 1.0);
 
                const double leftFactor = 1.0 - rightFactor;
                const double topFactor = 1.0 - bottomFactor;
 
                const T* const inputTopLeft = input.constpixel<T>(inputLeftPixel, inputTopPixel);
                const T* const inputTopRight = input.constpixel<T>(inputRightPixel, inputTopPixel);
 
                const T* const inputBottomLeft = input.constpixel<T>(inputLeftPixel, inputBottomPixel);
                const T* const inputBottomRight = input.constpixel<T>(inputRightPixel, inputBottomPixel);
 
                for (unsigned int n = 0u; n < channels; ++n)
                {
                    const double top = double(inputTopLeft[n]) * leftFactor + double(inputTopRight[n]) * rightFactor;
                    const double bottom = double(inputBottomLeft[n]) * leftFactor + double(inputBottomRight[n]) * rightFactor;
 
                    const double interpolated = top * topFactor + bottom * bottomFactor;
 
                    result[n] = T(interpolated);
                }
 
                // we do not check the result if we are very close to the frame boundaries
                if (Numeric::isNotEqual(inputPosition.x(), Scalar(0), frameBorderEps) && Numeric::isNotEqual(inputPosition.x(), Scalar(input.width() - 1u), frameBorderEps)
                        && Numeric::isNotEqual(inputPosition.y(), Scalar(0), frameBorderEps) && Numeric::isNotEqual(inputPosition.y(), Scalar(input.height() - 1u), frameBorderEps))
                {
                    for (unsigned int n = 0u; n < channels; ++n)
                    {
                        const double absError = NumericD::abs(double(result[n]) - double(outputPixel[n]));
 
                        sumAbsError += absError;
                        maxAbsError = max(maxAbsError, absError);
 
                        measurements++;
                    }
                }
 
                if (groundTruth != nullptr)
                {
                    memcpy(groundTruth->pixel<T>(xOutput, yOutput), result.data(), sizeof(T) * channels);
                }
            }
            else
            {
                // we do not check the result if we are very close to the frame boundaries
                if (Numeric::isNotEqual(inputPosition.x(), Scalar(0), frameBorderEps) && Numeric::isNotEqual(inputPosition.x(), Scalar(input.width() - 1u), frameBorderEps)
                        && Numeric::isNotEqual(inputPosition.y(), Scalar(0), frameBorderEps) && Numeric::isNotEqual(inputPosition.y(), Scalar(input.height() - 1u), frameBorderEps))
                {
                    for (unsigned int n = 0u; n < channels; ++n)
                    {
                        const double absError = NumericD::abs(double(backgroundColor[n]) - double(outputPixel[n]));
 
                        sumAbsError += absError;
                        maxAbsError = max(maxAbsError, absError);
 
                        measurements++;
                    }
                }
 
                if (groundTruth != nullptr)
                {
                    memcpy(groundTruth->pixel<T>(xOutput, yOutput), backgroundColor, sizeof(T) * channels);
                }
            }
        }
    }
 
    ocean_assert(measurements != 0ull || input.width() <= 2u || input.height() <= 2u || output.width() <= 2u || output.height() <= 2u);
 
    if (averageAbsError && measurements != 0ull)
    {
        *averageAbsError = sumAbsError / double(measurements);
    }
 
    if (maximalAbsError)
    {
        *maximalAbsError = maxAbsError;
    }
}
 
}
 
}
 
}
 
#endif // META_OCEAN_TEST_TESTCV_TEST_FRAME_INTERPOLATOR_BILINEAR_H