Compute Library
 19.08
CLEdgeNonMaxSuppressionKernel Class Reference

OpenCL kernel to perform Non-Maxima suppression for Canny Edge. More...

#include <CLCannyEdgeKernel.h>

Collaboration diagram for CLEdgeNonMaxSuppressionKernel:
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Public Member Functions

 CLEdgeNonMaxSuppressionKernel ()
 Constructor. More...
 
 CLEdgeNonMaxSuppressionKernel (const CLEdgeNonMaxSuppressionKernel &)=delete
 Prevent instances of this class from being copied (As this class contains pointers) More...
 
CLEdgeNonMaxSuppressionKerneloperator= (const CLEdgeNonMaxSuppressionKernel &)=delete
 Prevent instances of this class from being copied (As this class contains pointers) More...
 
void configure (const ICLTensor *magnitude, const ICLTensor *phase, ICLTensor *output, int32_t lower_thr, bool border_undefined)
 Initialise the kernel's sources, destination and border mode. More...
 
void run (const Window &window, cl::CommandQueue &queue) override
 Enqueue the OpenCL kernel to process the given window on the passed OpenCL command queue. More...
 
BorderSize border_size () const override
 The size of the border for that kernel. More...
 
- Public Member Functions inherited from ICLKernel
 ICLKernel ()
 Constructor. More...
 
cl::Kernel & kernel ()
 Returns a reference to the OpenCL kernel of this object. More...
 
template<typename T >
void add_1D_array_argument (unsigned int &idx, const ICLArray< T > *array, const Strides &strides, unsigned int num_dimensions, const Window &window)
 Add the passed 1D array's parameters to the object's kernel's arguments starting from the index idx. More...
 
void add_1D_tensor_argument (unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 1D tensor's parameters to the object's kernel's arguments starting from the index idx. More...
 
void add_1D_tensor_argument_if (bool cond, unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 1D tensor's parameters to the object's kernel's arguments starting from the index idx if the condition is true. More...
 
void add_2D_tensor_argument (unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 2D tensor's parameters to the object's kernel's arguments starting from the index idx. More...
 
void add_2D_tensor_argument_if (bool cond, unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 2D tensor's parameters to the object's kernel's arguments starting from the index idx if the condition is true. More...
 
void add_3D_tensor_argument (unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 3D tensor's parameters to the object's kernel's arguments starting from the index idx. More...
 
void add_4D_tensor_argument (unsigned int &idx, const ICLTensor *tensor, const Window &window)
 Add the passed 4D tensor's parameters to the object's kernel's arguments starting from the index idx. More...
 
template<typename T >
void add_argument (unsigned int &idx, T value)
 Add the passed parameters to the object's kernel's arguments starting from the index idx. More...
 
void set_lws_hint (const cl::NDRange &lws_hint)
 Set the Local-Workgroup-Size hint. More...
 
cl::NDRange lws_hint () const
 Return the Local-Workgroup-Size hint. More...
 
const std::string & config_id () const
 Get the configuration ID. More...
 
void set_target (GPUTarget target)
 Set the targeted GPU architecture. More...
 
void set_target (cl::Device &device)
 Set the targeted GPU architecture according to the CL device. More...
 
GPUTarget get_target () const
 Get the targeted GPU architecture. More...
 
size_t get_max_workgroup_size ()
 Get the maximum workgroup size for the device the CLKernelLibrary uses. More...
 
template<typename T , unsigned int dimension_size>
void add_array_argument (unsigned &idx, const ICLArray< T > *array, const Strides &strides, unsigned int num_dimensions, const Window &window)
 Add the passed array's parameters to the object's kernel's arguments starting from the index idx. More...
 
template<unsigned int dimension_size>
void add_tensor_argument (unsigned &idx, const ICLTensor *tensor, const Window &window)
 
- Public Member Functions inherited from IKernel
 IKernel ()
 Constructor. More...
 
virtual ~IKernel ()=default
 Destructor. More...
 
virtual bool is_parallelisable () const
 Indicates whether or not the kernel is parallelisable. More...
 
const Windowwindow () const
 The maximum window the kernel can be executed on. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from ICLKernel
static constexpr unsigned int num_arguments_per_1D_array ()
 Returns the number of arguments enqueued per 1D array object. More...
 
static constexpr unsigned int num_arguments_per_1D_tensor ()
 Returns the number of arguments enqueued per 1D tensor object. More...
 
static constexpr unsigned int num_arguments_per_2D_tensor ()
 Returns the number of arguments enqueued per 2D tensor object. More...
 
static constexpr unsigned int num_arguments_per_3D_tensor ()
 Returns the number of arguments enqueued per 3D tensor object. More...
 
static constexpr unsigned int num_arguments_per_4D_tensor ()
 Returns the number of arguments enqueued per 4D tensor object. More...
 
static cl::NDRange gws_from_window (const Window &window)
 Get the global work size given an execution window. More...
 

Detailed Description

OpenCL kernel to perform Non-Maxima suppression for Canny Edge.

Note
This kernel is meant to be used alongside CannyEdge and performs a non-maxima suppression using magnitude and phase of input to characterize points as possible edges. The output buffer needs to be cleared before this kernel is executed.
Hysteresis is computed in CLEdgeTraceKernel

Definition at line 75 of file CLCannyEdgeKernel.h.

Constructor & Destructor Documentation

◆ CLEdgeNonMaxSuppressionKernel() [1/2]

Constructor.

Definition at line 110 of file CLCannyEdgeKernel.cpp.

111  : _magnitude(nullptr), _phase(nullptr), _output(nullptr)
112 {
113 }

◆ CLEdgeNonMaxSuppressionKernel() [2/2]

Prevent instances of this class from being copied (As this class contains pointers)

Member Function Documentation

◆ border_size()

BorderSize border_size ( ) const
overridevirtual

The size of the border for that kernel.

Returns
The width in number of elements of the border.

Reimplemented from IKernel.

Definition at line 115 of file CLCannyEdgeKernel.cpp.

116 {
117  return BorderSize(1);
118 }
Container for 2D border size.
Definition: Types.h:259

Referenced by CLCannyEdge::configure(), and CLEdgeNonMaxSuppressionKernel::configure().

◆ configure()

void configure ( const ICLTensor magnitude,
const ICLTensor phase,
ICLTensor output,
int32_t  lower_thr,
bool  border_undefined 
)

Initialise the kernel's sources, destination and border mode.

Parameters
[in]magnitudeSource tensor - Magnitude. Data types supported: U16/U32.
[in]phaseSource tensor - Quantized phase. Data types supported: U8.
[out]outputDestination tensor. Data types supported: U16/U32.
[in]lower_thrLower threshold.
[in]border_undefinedTrue if the border mode is undefined. False if it's replicate or constant.

Definition at line 120 of file CLCannyEdgeKernel.cpp.

121 {
125 
126  _magnitude = magnitude;
127  _phase = phase;
128  _output = output;
129 
130  // Create build opts
131  std::set<std::string> built_opts;
132  built_opts.emplace("-DDATA_TYPE_IN=" + get_cl_type_from_data_type(magnitude->info()->data_type()));
133  built_opts.emplace("-DDATA_TYPE_OUT=" + get_cl_type_from_data_type(output->info()->data_type()));
134 
135  // Create kernel
136  const std::string kernel_name = std::string("suppress_non_maximum");
137  _kernel = static_cast<cl::Kernel>(CLKernelLibrary::get().create_kernel(kernel_name, built_opts));
138 
139  // Set minimum threshold argument
140  unsigned int idx = 3 * num_arguments_per_2D_tensor(); //Skip the input and output parameters
141  _kernel.setArg(idx++, lower_thr);
142 
143  // Configure kernel window
144  constexpr unsigned int num_elems_processed_per_iteration = 1;
145  constexpr unsigned int num_elems_read_written_per_iteration = 3;
146 
147  Window win = calculate_max_window(*_magnitude->info(), Steps(num_elems_processed_per_iteration), border_undefined, border_size());
148 
149  AccessWindowRectangle mag_access(_magnitude->info(), -border_size().left, -border_size().top,
150  num_elems_read_written_per_iteration, num_elems_read_written_per_iteration);
151  AccessWindowHorizontal phase_access(_phase->info(), 0, num_elems_processed_per_iteration);
152  AccessWindowHorizontal output_access(_output->info(), 0, num_elems_processed_per_iteration);
153 
154  update_window_and_padding(win, mag_access, phase_access, output_access);
155 
156  output_access.set_valid_region(win, _magnitude->info()->valid_region(), border_undefined, border_size());
157 
158  ICLKernel::configure_internal(win);
159 
160  // Set config_id for enabling LWS tuning
161  _config_id = kernel_name;
162  _config_id += "_";
163  _config_id += lower_string(string_from_data_type(output->info()->data_type()));
164  _config_id += "_";
165  _config_id += support::cpp11::to_string(output->info()->dimension(0));
166  _config_id += "_";
167  _config_id += support::cpp11::to_string(output->info()->dimension(1));
168  _config_id += "_";
169  _config_id += support::cpp11::to_string(border_undefined);
170 }
unsigned int top
top of the border
Definition: Types.h:339
virtual size_t dimension(size_t index) const =0
Return the size of the requested dimension.
1 channel, 1 U8 per channel
std::string to_string(T &&value)
Convert integer and float values to string.
virtual DataType data_type() const =0
Data type used for each element of the tensor.
SimpleTensor< uint8_t > phase(const SimpleTensor< T > &gx, const SimpleTensor< T > &gy, PhaseType phase_type)
Definition: Phase.cpp:35
static CLKernelLibrary & get()
Access the KernelLibrary singleton.
1 channel, 1 U16 per channel
std::string lower_string(const std::string &val)
Lower a given string.
Definition: Utils.cpp:327
Window calculate_max_window(const ValidRegion &valid_region, const Steps &steps=Steps(), bool skip_border=false, BorderSize border_size=BorderSize())
Calculate the maximum window for a given tensor shape and border setting.
Definition: Helpers.cpp:28
virtual ValidRegion valid_region() const =0
Valid region of the tensor.
Implementation of a rectangular access pattern.
const std::string & string_from_data_type(DataType dt)
Convert a data type identity into a string.
Definition: Utils.cpp:144
bool update_window_and_padding(Window &win, Ts &&... patterns)
Update window and padding size for each of the access patterns.
Definition: Helpers.h:402
1 channel, 1 U32 per channel
Class to describe a number of elements in each dimension.
Definition: Steps.h:40
Implementation of a row access pattern.
std::string get_cl_type_from_data_type(const DataType &dt)
Translates a tensor data type to the appropriate OpenCL type.
Definition: CLHelpers.cpp:35
virtual ITensorInfo * info() const =0
Interface to be implemented by the child class to return the tensor's metadata.
static constexpr unsigned int num_arguments_per_2D_tensor()
Returns the number of arguments enqueued per 2D tensor object.
Definition: ICLKernel.h:192
std::unique_ptr< Kernel > create_kernel()
Helper function to create and return a unique_ptr pointed to a CL/GLES kernel object.
Definition: Helpers.h:86
unsigned int left
left of the border
Definition: Types.h:342
#define ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(t, c,...)
Definition: Validate.h:789
Describe a multidimensional execution window.
Definition: Window.h:39
SimpleTensor< T > magnitude(const SimpleTensor< T > &gx, const SimpleTensor< T > &gy, MagnitudeType magnitude_type)
Definition: Magnitude.cpp:35
BorderSize border_size() const override
The size of the border for that kernel.

References ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN, CLEdgeNonMaxSuppressionKernel::border_size(), arm_compute::calculate_max_window(), arm_compute::create_kernel(), ITensorInfo::data_type(), ITensorInfo::dimension(), CLKernelLibrary::get(), arm_compute::get_cl_type_from_data_type(), ITensor::info(), BorderSize::left, arm_compute::lower_string(), arm_compute::test::validation::reference::magnitude(), ICLKernel::num_arguments_per_2D_tensor(), arm_compute::test::validation::reference::phase(), arm_compute::string_from_data_type(), arm_compute::support::cpp11::to_string(), BorderSize::top, arm_compute::U16, arm_compute::U32, arm_compute::U8, arm_compute::update_window_and_padding(), and ITensorInfo::valid_region().

Referenced by CLCannyEdge::configure().

◆ operator=()

Prevent instances of this class from being copied (As this class contains pointers)

◆ run()

void run ( const Window window,
cl::CommandQueue &  queue 
)
overridevirtual

Enqueue the OpenCL kernel to process the given window on the passed OpenCL command queue.

Note
The queue is not flushed by this method, and therefore the kernel will not have been executed by the time this method returns.
Parameters
[in]windowRegion on which to execute the kernel. (Must be a valid region of the window returned by window()).
[in,out]queueCommand queue on which to enqueue the kernel.

Implements ICLKernel.

Definition at line 172 of file CLCannyEdgeKernel.cpp.

173 {
176 
178  do
179  {
180  unsigned int idx = 0;
181  add_2D_tensor_argument(idx, _magnitude, slice);
182  add_2D_tensor_argument(idx, _phase, slice);
183  add_2D_tensor_argument(idx, _output, slice);
184  enqueue(queue, *this, slice, lws_hint());
185  }
187 }
Window first_slice_window_2D() const
First 2D slice of the window.
Definition: Window.h:267
const Window & window() const
The maximum window the kernel can be executed on.
Definition: IKernel.cpp:28
void enqueue(cl::CommandQueue &queue, ICLKernel &kernel, const Window &window, const cl::NDRange &lws_hint=CLKernelLibrary::get().default_ndrange(), bool use_dummy_work_items=false)
Add the kernel to the command queue with the given window.
Definition: ICLKernel.cpp:39
cl::NDRange lws_hint() const
Return the Local-Workgroup-Size hint.
Definition: ICLKernel.h:247
bool slide_window_slice_2D(Window &slice) const
Slide the passed 2D window slice.
Definition: Window.h:307
void add_2D_tensor_argument(unsigned int &idx, const ICLTensor *tensor, const Window &window)
Add the passed 2D tensor's parameters to the object's kernel's arguments starting from the index idx.
Definition: ICLKernel.h:134
#define ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW(f, s)
Definition: Validate.h:205
Describe a multidimensional execution window.
Definition: Window.h:39
#define ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(k)
Definition: Validate.h:940
SimpleTensor< T > slice(const SimpleTensor< T > &src, Coordinates starts, Coordinates ends)

References ICLKernel::add_2D_tensor_argument(), ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW, ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL, arm_compute::enqueue(), Window::first_slice_window_2D(), ICLKernel::lws_hint(), arm_compute::test::validation::reference::slice(), Window::slide_window_slice_2D(), and IKernel::window().


The documentation for this class was generated from the following files: