1 /*
2 * Copyright (c) 2016-2020 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 "src/core/NEON/kernels/NECumulativeDistributionKernel.h"
25
26 #include "arm_compute/core/Error.h"
27 #include "arm_compute/core/Helpers.h"
28 #include "arm_compute/core/IDistribution1D.h"
29 #include "arm_compute/core/ILut.h"
30 #include "arm_compute/core/ITensor.h"
31 #include "arm_compute/core/Types.h"
32 #include "arm_compute/core/Validate.h"
33 #include "src/core/helpers/AutoConfiguration.h"
34 #include "src/core/helpers/WindowHelpers.h"
35
36 #include <algorithm>
37 #include <cmath>
38 #include <numeric>
39
40 using namespace arm_compute;
41
NECumulativeDistributionKernel()42 NECumulativeDistributionKernel::NECumulativeDistributionKernel()
43 : _input(nullptr), _distribution(nullptr), _cumulative_sum(nullptr), _output(nullptr)
44 {
45 }
46
is_parallelisable() const47 bool NECumulativeDistributionKernel::is_parallelisable() const
48 {
49 return false;
50 }
51
configure(const IImage * input,const IDistribution1D * distribution,IDistribution1D * cumulative_sum,ILut * output)52 void NECumulativeDistributionKernel::configure(const IImage *input, const IDistribution1D *distribution, IDistribution1D *cumulative_sum, ILut *output)
53 {
54 ARM_COMPUTE_ERROR_ON_NULLPTR(input, distribution, cumulative_sum, output);
55 ARM_COMPUTE_ERROR_ON_TENSOR_NOT_2D(input);
56
57 set_format_if_unknown(*input->info(), Format::U8);
58
59 ARM_COMPUTE_ERROR_ON(distribution->num_bins() != cumulative_sum->num_bins());
60 ARM_COMPUTE_ERROR_ON(distribution->num_bins() != output->num_elements());
61 ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(input, 1, DataType::U8);
62 ARM_COMPUTE_ERROR_ON(input->info()->data_type() != output->type());
63
64 _input = input;
65 _distribution = distribution;
66 _cumulative_sum = cumulative_sum;
67 _output = output;
68
69 INEKernel::configure(calculate_max_window(*input->info()));
70 }
71
run(const Window & window,const ThreadInfo & info)72 void NECumulativeDistributionKernel::run(const Window &window, const ThreadInfo &info)
73 {
74 ARM_COMPUTE_UNUSED(info);
75 ARM_COMPUTE_UNUSED(window);
76 ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
77 ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW(INEKernel::window(), window);
78 ARM_COMPUTE_ERROR_ON(_distribution->buffer() == nullptr);
79 ARM_COMPUTE_ERROR_ON(_cumulative_sum->buffer() == nullptr);
80 ARM_COMPUTE_ERROR_ON(_output->buffer() == nullptr);
81 ARM_COMPUTE_ERROR_ON_MSG(_distribution->num_bins() < 256, "Distribution must have 256 bins");
82
83 // Calculate the cumulative distribution (summed histogram).
84 const uint32_t *hist = _distribution->buffer();
85 uint32_t *cumulative_sum = _cumulative_sum->buffer();
86 uint8_t *output = _output->buffer();
87
88 // Calculate cumulative distribution
89 std::partial_sum(hist, hist + _histogram_size, cumulative_sum);
90
91 // Get the number of pixels that have the lowest value in the input image
92 const uint32_t cd_min = *std::find_if(hist, hist + _histogram_size, [](const uint32_t &v)
93 {
94 return v > 0;
95 });
96 const uint32_t image_size = cumulative_sum[_histogram_size - 1];
97
98 ARM_COMPUTE_ERROR_ON(cd_min > image_size);
99
100 // Create mapping lookup table
101 if(image_size == cd_min)
102 {
103 std::iota(output, output + _histogram_size, 0);
104 }
105 else
106 {
107 const float diff = image_size - cd_min;
108
109 for(unsigned int x = 0; x < _histogram_size; ++x)
110 {
111 output[x] = lround((cumulative_sum[x] - cd_min) / diff * 255.0f);
112 }
113 }
114 }
115