| /* |
| * Copyright (c) 2016-2018 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. |
| */ |
| #ifndef __ARM_COMPUTE_NEHISTOGRAMKERNEL_H__ |
| #define __ARM_COMPUTE_NEHISTOGRAMKERNEL_H__ |
| |
| #include "arm_compute/core/NEON/INEKernel.h" |
| #include "support/Mutex.h" |
| |
| #include <cstddef> |
| #include <cstdint> |
| |
| namespace arm_compute |
| { |
| class IDistribution1D; |
| class ITensor; |
| using IImage = ITensor; |
| |
| /** Interface for the histogram kernel */ |
| class NEHistogramKernel : public INEKernel |
| { |
| public: |
| const char *name() const override |
| { |
| return "NEHistogramKernel"; |
| } |
| /** Default constructor */ |
| NEHistogramKernel(); |
| /** Default destructor */ |
| ~NEHistogramKernel() = default; |
| /** Prevent instances of this class from being copied (As this class contains pointers) */ |
| NEHistogramKernel(const NEHistogramKernel &) = delete; |
| /** Prevent instances of this class from being copied (As this class contains pointers) */ |
| NEHistogramKernel &operator=(const NEHistogramKernel &) = delete; |
| /** Allow instances of this class to be moved */ |
| NEHistogramKernel(NEHistogramKernel &&) = default; |
| /** Allow instances of this class to be moved */ |
| NEHistogramKernel &operator=(NEHistogramKernel &&) = default; |
| |
| /** Set the input image and the distribution output. |
| * |
| * @param[in] input Source image. Data type supported: U8. |
| * @param[out] output Destination distribution. |
| * @param[in,out] local_hist Array that the threads use to save their local histograms. |
| * It's size should be equal to (number_of_threads * num_bins), |
| * and the Window::thread_id() is used to determine the part of the array |
| * used by each thread. |
| * @param[out] window_lut LUT with pre-calculated possible window values. |
| * The size of the LUT should be equal to max_range_size and it will be filled |
| * during the configure stage, while it re-used in every run, therefore can be |
| * safely shared among threads. |
| */ |
| void configure(const IImage *input, IDistribution1D *output, uint32_t *local_hist, uint32_t *window_lut); |
| /** Set the input image and the distribution output. |
| * |
| * @note Used for histogram of fixed size equal to 256 |
| * |
| * @param[in] input Source image. Data type supported: U8. |
| * @param[out] output Destination distribution which must be of 256 bins.. |
| */ |
| void configure(const IImage *input, IDistribution1D *output); |
| |
| // Inherited methods overridden: |
| void run(const Window &window, const ThreadInfo &info) override; |
| |
| private: |
| /** Function to merge multiple partial histograms. |
| * |
| * @param[out] global_hist Pointer to the final histogram. |
| * @param[in] local_hist Pointer to the partial histograms. |
| * @param[in] bins Number of bins. |
| */ |
| void merge_histogram(uint32_t *global_hist, const uint32_t *local_hist, size_t bins); |
| /** Function to merge multiple minimum values of partial histograms. |
| * |
| * @param[out] global_min Pointer to the global min value. |
| * @param[in] local_min Local min value. |
| */ |
| void merge_min(uint8_t *global_min, const uint8_t &local_min); |
| /** Function to perform histogram on the given window |
| * |
| * @param[in] win Region on which to execute the kernel |
| * @param[in] info Info about the executing thread |
| */ |
| void histogram_U8(Window win, const ThreadInfo &info); |
| /** Function to perform histogram on the given window where histogram is |
| * of fixed size 256 without ranges and offsets. |
| * |
| * @param[in] win Region on which to execute the kernel |
| * @param[in] info Info about the executing thread |
| */ |
| void histogram_fixed_U8(Window win, const ThreadInfo &info); |
| /** Pre-calculate the pixel windowing for every possible pixel |
| * |
| * Calculate (V - offset) * numBins / range where V is every possible pixel value. |
| * |
| * @note We currently support U8 image thus possible pixel values are between 0 and 255 |
| */ |
| void calculate_window_lut() const; |
| /** Common signature for all the specialised Histogram functions |
| * |
| * @param[in] window Region on which to execute the kernel. |
| */ |
| using HistogramFunctionPtr = void (NEHistogramKernel::*)(Window window, const ThreadInfo &info); |
| |
| HistogramFunctionPtr _func; ///< Histogram function to use for the particular image types passed to configure() |
| const IImage *_input; |
| IDistribution1D *_output; |
| uint32_t *_local_hist; |
| uint32_t *_window_lut; |
| arm_compute::Mutex _hist_mtx; |
| static constexpr unsigned int _max_range_size{ 256 }; ///< 256 possible pixel values as we handle only U8 images |
| }; |
| } // namespace arm_compute |
| #endif /*__ARM_COMPUTE_NEHISTOGRAMKERNEL_H__ */ |