src/core/NEON/kernels/NEGaussian3x3Kernel.cpp

   1 /*
   2  * Copyright (c) 2016, 2017 ARM Limited.
   3  *
   4  * SPDX-License-Identifier: MIT
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to
   8  * deal in the Software without restriction, including without limitation the
   9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  10  * sell copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in all
  14  * copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24 #include "arm_compute/core/NEON/kernels/NEGaussian3x3Kernel.h"
  25
  26 #include "arm_compute/core/Coordinates.h"
  27 #include "arm_compute/core/Helpers.h"
  28 #include "arm_compute/core/ITensor.h"
  29 #include "arm_compute/core/NEON/INEKernel.h"
  30 #include "arm_compute/core/Validate.h"
  31
  32 #include <arm_neon.h>
  33
  34 using namespace arm_compute;
  35
  36 BorderSize NEGaussian3x3Kernel::border_size() const
  37 {
  38     return BorderSize(1);
  39 }
  40
  41 void NEGaussian3x3Kernel::configure(const ITensor *input, ITensor *output, bool border_undefined)
  42 {
  43     ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(input, 1, DataType::U8);
  44     ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(output, 1, DataType::U8);
  45
  46     _input  = input;
  47     _output = output;
  48
  49     // Configure kernel window
  50     constexpr unsigned int num_elems_processed_per_iteration = 8;
  51     constexpr unsigned int num_elems_read_per_iteration      = 16;
  52     constexpr unsigned int num_elems_written_per_iteration   = 8;
  53     constexpr unsigned int num_rows_read_per_iteration       = 3;
  54
  55     Window                 win = calculate_max_window(*input->info(), Steps(num_elems_processed_per_iteration), border_undefined, border_size());
  56     AccessWindowHorizontal output_access(output->info(), 0, num_elems_written_per_iteration);
  57
  58     update_window_and_padding(win,
  59                               AccessWindowRectangle(input->info(), -border_size().left, -border_size().top, num_elems_read_per_iteration, num_rows_read_per_iteration),
  60                               output_access);
  61
  62     output_access.set_valid_region(win, input->info()->valid_region(), border_undefined, border_size());
  63
  64     INEKernel::configure(win);
  65 }
  66
  67 void NEGaussian3x3Kernel::run(const Window &window)
  68 {
  69     ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
  70     ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW(INESimpleKernel::window(), window);
  71
  72     Iterator input(_input, window);
  73     Iterator output(_output, window);
  74
  75     const uint8_t *input_bot_ptr = _input->ptr_to_element(Coordinates(-1, -1));
  76     const uint8_t *input_mid_ptr = _input->ptr_to_element(Coordinates(-1, 0));
  77     const uint8_t *input_top_ptr = _input->ptr_to_element(Coordinates(-1, +1));
  78
  79     static const int16x8_t two  = vdupq_n_s16(2);
  80     static const int16x8_t four = vdupq_n_s16(4);
  81
  82     execute_window_loop(window, [&](const Coordinates & id)
  83     {
  84         uint8x16_t top_data = vld1q_u8(input_top_ptr + input.offset());
  85         uint8x16_t mid_data = vld1q_u8(input_mid_ptr + input.offset());
  86         uint8x16_t bot_data = vld1q_u8(input_bot_ptr + input.offset());
  87
  88         const int16x8x2_t top_s16 =
  89         {
  90             {
  91                 vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(top_data))),
  92                 vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(top_data)))
  93             }
  94         };
  95         const int16x8x2_t mid_s16 =
  96         {
  97             {
  98                 vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(mid_data))),
  99                 vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(mid_data)))
 100             }
 101         };
 102         const int16x8x2_t bot_s16 =
 103         {
 104             {
 105                 vreinterpretq_s16_u16(vmovl_u8(vget_low_u8(bot_data))),
 106                 vreinterpretq_s16_u16(vmovl_u8(vget_high_u8(bot_data)))
 107             }
 108         };
 109
 110         //top left
 111         int16x8_t out = top_s16.val[0];
 112         //top mid
 113         out = vmlaq_s16(out, vextq_s16(top_s16.val[0], top_s16.val[1], 1), two);
 114         //top right
 115         out = vaddq_s16(out, vextq_s16(top_s16.val[0], top_s16.val[1], 2));
 116         //mid left
 117         out = vmlaq_s16(out, mid_s16.val[0], two);
 118         //mid mid
 119         out = vmlaq_s16(out, vextq_s16(mid_s16.val[0], mid_s16.val[1], 1), four);
 120         //mid right
 121         out = vmlaq_s16(out, vextq_s16(mid_s16.val[0], mid_s16.val[1], 2), two);
 122         //bot left
 123         out = vaddq_s16(out, bot_s16.val[0]);
 124         //bot mid
 125         out = vmlaq_s16(out, vextq_s16(bot_s16.val[0], bot_s16.val[1], 1), two);
 126         //bot right
 127         out = vaddq_s16(out, vextq_s16(bot_s16.val[0], bot_s16.val[1], 2));
 128
 129         vst1_u8(output.ptr(), vqshrun_n_s16(out, 4));
 130     },
 131     input, output);
 132 }