text: /*
   * Copyright (c) 2016, 2017 ARM Limited.
   *
   * SPDX-License-Identifier: MIT
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to
   * deal in the Software without restriction, including without limitation the
   * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   * sell copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all
   * copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  #include "arm_compute/runtime/CL/functions/CLFastCorners.h"
  
  #include "arm_compute/core/CL/OpenCL.h"
  #include "arm_compute/core/CL/kernels/CLFastCornersKernel.h"
  #include "arm_compute/core/Error.h"
  #include "arm_compute/core/TensorInfo.h"
  #include "arm_compute/core/Validate.h"
  #include "arm_compute/runtime/CL/CLScheduler.h"
  #include "arm_compute/runtime/ITensorAllocator.h"
  
  #include <algorithm>
  #include <cstring>
  
  using namespace arm_compute;
  
  CLFastCorners::CLFastCorners()
      : _fast_corners_kernel(),
        _suppr_func(),
        _copy_array_kernel(),
        _output(),
        _suppr(),
        _win(),
        _non_max(false),
        _num_corners(nullptr),
        _num_buffer(),
        _corners(nullptr),
        _constant_border_value(0)
  {
  }
  
  void CLFastCorners::configure(const ICLImage *input, float threshold, bool nonmax_suppression, CLKeyPointArray *const corners,
                                unsigned int *num_corners, BorderMode border_mode, uint8_t constant_border_value)
  {
      ARM_COMPUTE_ERROR_ON_TENSOR_NOT_2D(input);
      ARM_COMPUTE_ERROR_ON(BorderMode::UNDEFINED != border_mode);
      ARM_COMPUTE_ERROR_ON(nullptr == corners);
      ARM_COMPUTE_ERROR_ON(threshold < 1 && threshold > 255);
  
      TensorInfo tensor_info(input->info()->tensor_shape(), 1, DataType::U8);
      _output.allocator()->init(tensor_info);
  
      _non_max               = nonmax_suppression;
      _num_corners           = num_corners;
      _corners               = corners;
      _num_buffer            = cl::Buffer(CLScheduler::get().context(), CL_MEM_ALLOC_HOST_PTR | CL_MEM_READ_WRITE, sizeof(unsigned int));
      _constant_border_value = constant_border_value;
  
      const bool update_number = (nullptr != _num_corners);
  
      _fast_corners_kernel.configure(input, &_output, threshold, nonmax_suppression, border_mode);
  
      if(!_non_max)
      {
          _copy_array_kernel.configure(&_output, update_number, corners, &_num_buffer);
      }
      else
      {
          _suppr.allocator()->init(tensor_info);
  
          _suppr_func.configure(&_output, &_suppr, border_mode);
          _copy_array_kernel.configure(&_suppr, update_number, corners, &_num_buffer);
  
          _suppr.allocator()->allocate();
      }
  
      // Allocate intermediate tensors
      _output.allocator()->allocate();
  }
  
  void CLFastCorners::run()
  {
      cl::CommandQueue q = CLScheduler::get().queue();
  
      if(_non_max)
      {
          ARM_COMPUTE_ERROR_ON_MSG(_output.cl_buffer().get() == nullptr, "Unconfigured function");
          const auto out_buffer = static_cast<unsigned char *>(q.enqueueMapBuffer(_output.cl_buffer(), CL_TRUE, CL_MAP_WRITE, 0, _output.info()->total_size()));
          memset(out_buffer, 0, _output.info()->total_size());
          q.enqueueUnmapMemObject(_output.cl_buffer(), out_buffer);
      }
  
      CLScheduler::get().enqueue(_fast_corners_kernel, false);
  
      if(_non_max)
      {
          _suppr_func.run();
      }
  
      CLScheduler::get().enqueue(_copy_array_kernel, false);
  
      unsigned int get_num_corners = 0;
      q.enqueueReadBuffer(_num_buffer, CL_TRUE, 0, sizeof(unsigned int), &get_num_corners);
  
      size_t corner_size = std::min(static_cast<size_t>(get_num_corners), _corners->max_num_values());
  
      _corners->resize(corner_size);
  
      if(_num_corners != nullptr)
      {
          *_num_corners = get_num_corners;
      }
  
      q.flush();
  }
  