CUDA小白 - NPP(8) 图像处理 Morphological Operations

cuda小白

原始API链接 NPP

GPU架构近些年也有不少的变化，具体的可以参考别的博主的介绍，都比较详细。还有一些cuda中的专有名词的含义，可以参考《详解CUDA的Context、Stream、Warp、SM、SP、Kernel、Block、Grid》

常见的NppStatus，可以看这里。

7 是图像的傅里叶变换，还在学习中

本文主要讲述的是形态学变换

Dilation

膨胀操作（对二值化物体边界点进行扩充，将与物体接触的所有背景点合并到该物体中，使边界向外部扩张。如果两个物体间隔较近，会将两物体连通在一起。）

// 返回mask下的最大像素值作为输出的pixel，如果mask的值为0，则不参与最大值查询
NppStatus nppiDilate_8u_C3R(const Npp8u *pSrc,
							Npp32s nSrcStep,
							Npp8u *pDst,
							Npp32s nDstStep,
							NppiSize oSizeROI,
							const Npp8u *pMask,
							NppiSize oMaskSize,
							NppiPoint oAnchor);
// 与前一个接口的区别是多了一个borderType的类型指定
/* 
NppiBorderType {
  NPP_BORDER_UNDEFINED,
  NPP_BORDER_NONE,
  NPP_BORDER_CONSTANT,
  NPP_BORDER_REPLICATE,
  NPP_BORDER_WARP,
  NPP_BORDER_MIRROR	
};
*/
NppStatus nppiDilateBorder_8u_C3R(const Npp8u *pSrc,
								  Npp32s nSrcStep,
								  NppiSize oSrcSize,
								  NppiPoint oSrcOffset,
								  Npp8u *pDst,
								  Npp32s nDstStep,
								  NppiSize oSizeROI,
								  const Npp8u *pMask,
								  NppiSize oMaskSize,
								  NppiPoint oAnchor,
								  NppiBorderType eBorderType);
// 特定大小的kernel
NppStatus nppiDilate3x3_8u_C3R(const Npp8u *pSrc,
							   Npp32s nSrcStep,
							   Npp8u *pDst,
						       Npp32s nDstStep,
							   NppiSize oSizeROI);

code

#include <iostream>
#include <cuda_runtime.h>
#include <npp.h>
#include <opencv2/opencv.hpp>

#define CUDA_FREE(ptr) { if (ptr != nullptr) { cudaFree(ptr); ptr = nullptr; } }

int main() {
  std::string directory = "../";
  cv::Mat image_dog = cv::imread(directory + "dog.png");
  int image_width = image_dog.cols;
  int image_height = image_dog.rows;
  int image_size = image_width * image_height;

  // =============== device memory ===============
  // input
  uint8_t *in_image;
  cudaMalloc((void**)&in_image, image_size * 3 * sizeof(uint8_t));
  cudaMemcpy(in_image, image_dog.data, image_size * 3 * sizeof(uint8_t), cudaMemcpyHostToDevice);

  // output
  uint8_t *out_ptr1, *out_ptr2;
  cudaMalloc((void**)&out_ptr1, image_size * 3 * sizeof(uint8_t));  // 三通道
  cudaMalloc((void**)&out_ptr2, image_size * 3 * sizeof(uint8_t));  // 三通道

  NppiSize in_size;
  in_size.width = image_width;
  in_size.height = image_height;
  NppiRect rc;
  rc.x = 0;
  rc.y = 0;
  rc.width = image_width;
  rc.height = image_height;

  int mask_size = 10;
  cv::Mat mat_mask = cv::Mat::ones(mask_size, mask_size, CV_8UC1);
  uint8_t *mask;
  cudaMalloc((void**)&mask, mask_size * mask_size * sizeof(uint8_t));
  cudaMemcpy(mask, mat_mask.data, mask_size * mask_size * sizeof(uint8_t), cudaMemcpyHostToDevice);

  cv::Mat out_image = cv::Mat::zeros(image_height, image_width, CV_8UC3);
  NppStatus status;
  NppiSize npp_mask_size;
  npp_mask_size.width = mask_size;
  npp_mask_size.height = mask_size;
  NppiPoint pt;
  pt.x = 0;
  pt.y = 0;
  // =============== nppiDilate_8u_C3R ===============
  status = nppiDilate_8u_C3R(in_image, image_width * 3, out_ptr1, image_width * 3, 
                             in_size, mask, npp_mask_size, pt);
  if (status != NPP_SUCCESS) {
    std::cout << "[GPU] ERROR nppiDilate_8u_C3R failed, status = " << status << std::endl;
    return false;
  }
  cudaMemcpy(out_image.data, out_ptr1, image_size * 3, cudaMemcpyDeviceToHost);
  cv::imwrite(directory + "dilate.jpg", out_image);

  // =============== nppiDilateBorder_8u_C3R ===============
  NppiPoint src_pt;
  src_pt.x = 100;
  src_pt.y = 100;
  status = nppiDilateBorder_8u_C3R(in_image, image_width * 3, in_size, src_pt, out_ptr2, 
                                   image_width * 3, in_size, mask, npp_mask_size, pt, 
                                   NPP_BORDER_REPLICATE);
  if (status != NPP_SUCCESS) {
    std::cout << "[GPU] ERROR nppiDilateBorder_8u_C3R failed, status = " << status << std::endl;
    return false;
  }
  cudaMemcpy(out_image.data, out_ptr2, image_size * 3, cudaMemcpyDeviceToHost);
  cv::imwrite(directory + "dilate_border.jpg", out_image);

  // free
  CUDA_FREE(in_image)
  CUDA_FREE(out_ptr1)
  CUDA_FREE(out_ptr2)
}

make

cmake_minimum_required(VERSION 3.20)
project(test)

find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})

find_package(CUDA REQUIRED)
include_directories(${CUDA_INCLUDE_DIRS})
file(GLOB CUDA_LIBS "/usr/local/cuda/lib64/*.so")

add_executable(test test.cpp)
target_link_libraries(test
                      ${OpenCV_LIBS}
                      ${CUDA_LIBS}
)

result

注意：

1. nppiDilateBorder_8u_C3R 仅支持border的模式为 NPP_BORDER_REPLICATE，其他模式会报错，错误码为-9999。

Erode

腐蚀操作

NppStatus nppiErode_8u_C3R(const Npp8u *pSrc,
						   Npp32s nSrcStep,
					       Npp8u *pDst,
						   Npp32s nDstStep,
						   NppiSize oSizeROI,
						   const Npp8u *pMask,
						   NppiSize oMaskSize,
						   NppiPoint oAnchor);
NppStatus nppiErodeBorder_8u_C3R(const Npp8u *pSrc,
								 Npp32s nSrcStep,
								 NppiSize oSrcSize,
								 NppiPoint oSrcOffset,
								 Npp8u *pDst,
								 Npp32s nDstStep,
								 NppiSize oSizeROI,
								 const Npp8u *pMask,
								 NppiSize oMaskSize,
								 NppiPoint oAnchor,
								 NppiBorderType eBorderType);
// 固定大小的Erode
NppStatus nppiErode3x3_8u_C3R(const Npp8u *pSrc,
							  Npp32s nSrcStep,
							  Npp8u *pDst,
							  Npp32s nDstStep,
							  NppiSize oSizeROI);
// nppiErode3x3Border_8u_C3R 不详细介绍了

再此使用上一个实验膨胀之后的图像作为腐蚀的输入。

code

#include <iostream>
#include <cuda_runtime.h>
#include <npp.h>
#include <opencv2/opencv.hpp>

#define CUDA_FREE(ptr) { if (ptr != nullptr) { cudaFree(ptr); ptr = nullptr; } }

int main() {
  std::string directory = "../";
  cv::Mat image_dog = cv::imread(directory + "dilate.jpg");
  int image_width = image_dog.cols;
  int image_height = image_dog.rows;
  int image_size = image_width * image_height;

  // =============== device memory ===============
  // input
  uint8_t *in_image;
  cudaMalloc((void**)&in_image, image_size * 3 * sizeof(uint8_t));
  cudaMemcpy(in_image, image_dog.data, image_size * 3 * sizeof(uint8_t), cudaMemcpyHostToDevice);

  // output
  uint8_t *out_ptr1, *out_ptr2;
  cudaMalloc((void**)&out_ptr1, image_size * 3 * sizeof(uint8_t));  // 三通道
  cudaMalloc((void**)&out_ptr2, image_size * 3 * sizeof(uint8_t));  // 三通道

  NppiSize in_size;
  in_size.width = image_width;
  in_size.height = image_height;
  NppiRect rc;
  rc.x = 0;
  rc.y = 0;
  rc.width = image_width;
  rc.height = image_height;

  int mask_size = 10;
  cv::Mat mat_mask = cv::Mat::ones(mask_size, mask_size, CV_8UC1);
  uint8_t *mask;
  cudaMalloc((void**)&mask, mask_size * mask_size * sizeof(uint8_t));
  cudaMemcpy(mask, mat_mask.data, mask_size * mask_size * sizeof(uint8_t), cudaMemcpyHostToDevice);

  cv::Mat out_image = cv::Mat::zeros(image_height, image_width, CV_8UC3);
  NppStatus status;
  NppiSize npp_mask_size;
  npp_mask_size.width = mask_size;
  npp_mask_size.height = mask_size;
  NppiPoint pt;
  pt.x = 0;
  pt.y = 0;
  // =============== nppiErode_8u_C3R ===============
  status = nppiErode_8u_C3R(in_image, image_width * 3, out_ptr1, image_width * 3, 
                            in_size, mask, npp_mask_size, pt);
  if (status != NPP_SUCCESS) {
    std::cout << "[GPU] ERROR nppiErode_8u_C3R failed, status = " << status << std::endl;
    return false;
  }
  cudaMemcpy(out_image.data, out_ptr1, image_size * 3, cudaMemcpyDeviceToHost);
  cv::imwrite(directory + "erode.jpg", out_image);

  // =============== nppiErodeBorder_8u_C3R ===============
  NppiPoint src_pt;
  src_pt.x = 100;
  src_pt.y = 100;
  status = nppiErodeBorder_8u_C3R(in_image, image_width * 3, in_size, src_pt, out_ptr2, 
                                  image_width * 3, in_size, mask, npp_mask_size, pt, 
                                  NPP_BORDER_REPLICATE);
  if (status != NPP_SUCCESS) {
    std::cout << "[GPU] ERROR nppiErodeBorder_8u_C3R failed, status = " << status << std::endl;
    return false;
  }
  cudaMemcpy(out_image.data, out_ptr2, image_size * 3, cudaMemcpyDeviceToHost);
  cv::imwrite(directory + "erode_border.jpg", out_image);

  // free
  CUDA_FREE(in_image)
  CUDA_FREE(out_ptr1)
  CUDA_FREE(out_ptr2)
}

make

cmake_minimum_required(VERSION 3.20)
project(test)

find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})

find_package(CUDA REQUIRED)
include_directories(${CUDA_INCLUDE_DIRS})
file(GLOB CUDA_LIBS "/usr/local/cuda/lib64/*.so")

add_executable(test test.cpp)
target_link_libraries(test
                      ${OpenCV_LIBS}
                      ${CUDA_LIBS}
)

result

注意点：

1. nppiErodeBorder_8u_C3R 仅支持border的模式为 NPP_BORDER_REPLICATE，其他模式会报错，错误码为-9999。

ComplexImageMorphology

复杂图像形态学，暂时不做介绍，后续视情况而定
<<<链接>>>