我需要在我的课程项目中使用OpenCV的GPU库。我正在处理一个现有的代码,其中使用了OpenCV Python,我的任务是找到一种方法来访问OpenCV的CUDA库,因为现在没有可访问的Python绑定到OpenCV的各种CUDA模块。
我现在非常需要的两个函数是cuda :: warpPerspective
和cv :: cuda :: DescriptorMatcher :: knnMatch()
。
我尝试通过遵循@ostrumvulpes在Accessing OpenCV CUDA Functions from Python (No PyCUDA)中建议的方法实现warpPerspective
,它完美地工作。现在我卡在了DescriptorMatcher :: knnMatch()
上。更准确地说,我需要使用暴力描述符匹配器的knnmatch
函数(CUDA)。我在网上搜索了用C ++编写的示例,以便我可以初步了解如何通过cython进行转换以使其正常工作。
我找到的大多数示例都像以下示例:
Ptr<cuda::DescriptorMatcher> matcher =
cuda::DescriptorMatcher::createBFMatcher();
vector< vector< DMatch> > matches;
matcher->knnMatch(descriptors_object_Gpu, descriptors_scene_Gpu, matches, 2);
为了实现这三行代码,我首先在.pxd文件中添加了我认为必要的内容。我的pxd文件如下所示: GpuWrapper.pxd
from libcpp cimport bool
from cpython.ref cimport PyObject
from libcpp.vector cimport vector
# References PyObject to OpenCV object conversion code borrowed from OpenCV's own conversion file, cv2.cpp
cdef extern from 'pyopencv_converter.cpp':
#mrc689 April 20,2017
void import_array()
cdef PyObject* pyopencv_from(const Mat& m)
cdef bool pyopencv_to(PyObject* o, Mat& m)
cdef extern from 'opencv2/imgproc.hpp' namespace 'cv':
cdef enum InterpolationFlags:
INTER_NEAREST = 0
cdef enum ColorConversionCodes:
COLOR_BGR2GRAY
cdef extern from 'opencv2/core/core.hpp':
cdef int CV_8UC1
cdef int CV_32FC1
cdef extern from 'opencv2/core/core.hpp' namespace 'cv':
cdef cppclass Size_[T]:
Size_() except +
Size_(T width, T height) except +
T width
T height
ctypedef Size_[int] Size2i
ctypedef Size2i Size
cdef cppclass Scalar[T]:
Scalar() except +
Scalar(T v0) except +
cdef extern from 'opencv2/core/core.hpp' namespace 'cv':
cdef cppclass Mat:
Mat() except +
void create(int, int, int) except +
void* data
int rows
int cols
#added to test the Algorithm class inside core.hpp on May5th 12.52 AM.
cdef cppclass Algorithm:
Algorithm() except +
cdef extern from 'opencv2/core/base.hpp' namespace 'cv':
cdef enum NormTypes:
NORM_INF= 1,
NORM_L1= 2,
NORM_L2= 4,
NORM_HAMMING= 6,
NORM_HAMMING2= 7,
cdef extern from 'opencv2/core/cuda.hpp' namespace 'cv::cuda':
cdef cppclass GpuMat:
GpuMat() except +
void upload(Mat arr) except +
void download(Mat dst) const
cdef cppclass Stream:
Stream() except +
cdef extern from 'opencv2/core/types.hpp' namespace 'cv':
cdef cppclass DMatch:
DMatch() except +
float distance
int imgIdx
int queryIdx
int trainIdx
cdef extern from 'opencv2/core/cvstd.hpp' namespace 'cv':
cdef cppclass Ptr[T]:
T element_type
Ptr() except +
cdef extern from 'opencv2/cudafeatures2d.hpp' namespace 'cv::cuda':
cdef cppclass DescriptorMatcher:
@staticmethod
Ptr[DescriptorMatcher] createBFMatcher(int normType) except+
#Expected to see error here
void knnMatch(GpuMat queryDescriptors, GpuMat trainDescriptors, vector[vector[DMatch]] &matches,int k)
cdef extern from 'opencv2/cudawarping.hpp' namespace 'cv::cuda':
cdef void warpPerspective(GpuMat src, GpuMat dst, Mat M, Size dsize, int flags, int borderMode, Scalar borderValue, Stream& stream)
# Function using default values
cdef void warpPerspective(GpuMat src, GpuMat dst, Mat M, Size dsize, int flags)
我的 pyx 文件长这样:
GpuWrapper.pyx
import numpy as np # Import Python functions, attributes, submodules of numpy
cimport numpy as np # Import numpy C/C++ API
def match_feature(np.ndarray[np.float32_t, ndim=3] _src,
np.ndarray[np.float32_t, ndim=2] _M):
np.import_array()
# Create GPU/device InputArray for src
cdef Mat src_mat
cdef GpuMat src_gpu
pyopencv_to(<PyObject*> _src, src_mat)
src_gpu.upload(src_mat)
cdef Mat src_mat_2
cdef GpuMat src_gpu_2
pyopencv_to(<PyObject*> _M, src_mat_2)
src_gpu_2.upload(src_mat_2)
cdef Ptr[DescriptorMatcher] matcher= Ptr()
matcher = DescriptorMatcher.createBFMatcher(4)
cdef vector[vector[DMatch]] matches
matcher.knnMatch(src_gpu,src_gpu_2,matches,2)
print("no problem so far")
我试图编译它时遇到了一个错误,错误信息是'Ptr[DescriptorMatcher]'没有属性'knnMatch'
。
据我理解,Ptr是DescriptorMatcher类型的共享指针,所以我的从.pxd文件中定义Ptr的方式应该有问题。
我不知道如何解决它。如果有人能帮助我解决这个问题,我会非常感激。