COMPMID-344 Updated doxygen
Change-Id: I32f7b84daa560e460b77216add529c8fa8b327ae
diff --git a/src/core/NEON/kernels/NEIntegralImageKernel.cpp b/src/core/NEON/kernels/NEIntegralImageKernel.cpp
new file mode 100644
index 0000000..3b09a1b
--- /dev/null
+++ b/src/core/NEON/kernels/NEIntegralImageKernel.cpp
@@ -0,0 +1,141 @@
+/*
+ * 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/core/NEON/kernels/NEIntegralImageKernel.h"
+
+#include "arm_compute/core/Coordinates.h"
+#include "arm_compute/core/Helpers.h"
+#include "arm_compute/core/ITensor.h"
+#include "arm_compute/core/Types.h"
+#include "arm_compute/core/Validate.h"
+
+#include <arm_neon.h>
+#include <cstddef>
+#include <cstdint>
+
+using namespace arm_compute;
+
+void NEIntegralImageKernel::configure(const ITensor *input, ITensor *output)
+{
+ ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(input, 1, DataType::U8);
+ ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(output, 1, DataType::U32);
+
+ _input = input;
+ _output = output;
+
+ constexpr unsigned int num_elems_processed_per_iteration = 16;
+
+ // Configure kernel window
+ Window win = calculate_max_window(*input->info(), Steps(num_elems_processed_per_iteration));
+ // The kernel is effectively reading 17 values from -1 as it loads 16
+ // starting at -1 and also 16 starting at 0
+ AccessWindowRectangle output_read_access(output->info(), -1, -1, num_elems_processed_per_iteration + 1, 1);
+ AccessWindowHorizontal output_write_access(output->info(), 0, num_elems_processed_per_iteration);
+
+ update_window_and_padding(win,
+ AccessWindowHorizontal(input->info(), 0, num_elems_processed_per_iteration),
+ output_read_access, output_write_access);
+
+ output_write_access.set_valid_region(win, input->info()->valid_region());
+
+ IKernel::configure(win);
+}
+
+BorderSize NEIntegralImageKernel::border_size() const
+{
+ return BorderSize(1, 0, 0, 1);
+}
+
+bool NEIntegralImageKernel::is_parallelisable() const
+{
+ return false;
+}
+
+void NEIntegralImageKernel::run(const Window &window)
+{
+ ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
+ ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW(INESimpleKernel::window(), window);
+
+ Iterator input(_input, window);
+ Iterator output(_output, window);
+
+ const auto output_top_left = reinterpret_cast<const uint32_t *>(_output->ptr_to_element(Coordinates(-1, -1)));
+ const auto output_top_mid = reinterpret_cast<const uint32_t *>(_output->ptr_to_element(Coordinates(0, -1)));
+
+ execute_window_loop(window, [&](const Coordinates & id)
+ {
+ const uint8x16_t input_pixels = vld1q_u8(input.ptr());
+
+ const uint16x8x2_t tmp =
+ {
+ {
+ vmovl_u8(vget_low_u8(input_pixels)),
+ vmovl_u8(vget_high_u8(input_pixels))
+ }
+ };
+
+ uint32x4x4_t pixels =
+ {
+ {
+ vmovl_u16(vget_low_u16(tmp.val[0])),
+ vmovl_u16(vget_high_u16(tmp.val[0])),
+ vmovl_u16(vget_low_u16(tmp.val[1])),
+ vmovl_u16(vget_high_u16(tmp.val[1]))
+ }
+ };
+
+ // Divide by four as pointer is now uint32 instead of uint8!
+ const size_t off = output.offset() / 4;
+
+ // Add top mid pixel values
+ const uint32_t *const top_mid_ptr = output_top_mid + off;
+
+ pixels.val[0] = vaddq_u32(vld1q_u32(top_mid_ptr), pixels.val[0]);
+ pixels.val[1] = vaddq_u32(vld1q_u32(top_mid_ptr + 4), pixels.val[1]);
+ pixels.val[2] = vaddq_u32(vld1q_u32(top_mid_ptr + 8), pixels.val[2]);
+ pixels.val[3] = vaddq_u32(vld1q_u32(top_mid_ptr + 12), pixels.val[3]);
+
+ // Subtract top left diagonal values
+ const auto outptr = reinterpret_cast<uint32_t *>(output.ptr());
+ const uint32_t *const top_left_ptr = output_top_left + off;
+
+ pixels.val[0] = vsubq_u32(pixels.val[0], vld1q_u32(top_left_ptr));
+ vst1q_u32(outptr, pixels.val[0]);
+
+ pixels.val[1] = vsubq_u32(pixels.val[1], vld1q_u32(top_left_ptr + 4));
+ vst1q_u32(outptr + 4, pixels.val[1]);
+
+ pixels.val[2] = vsubq_u32(pixels.val[2], vld1q_u32(top_left_ptr + 8));
+ vst1q_u32(outptr + 8, pixels.val[2]);
+
+ pixels.val[3] = vsubq_u32(pixels.val[3], vld1q_u32(top_left_ptr + 12));
+ vst1q_u32(outptr + 12, pixels.val[3]);
+
+ // Perform prefix summation
+ for(auto i = 0; i < 16; ++i)
+ {
+ outptr[i] += outptr[i - 1];
+ }
+ },
+ input, output);
+}