对于我的课程项目之一,我需要使用OpenCV GPU库。我正在使用OpenCV python的现有代码,我的工作是寻找访问OpenCV Cuda库的方法,因为现在没有可访问的OpenCV各种CUDA模块的Python绑定。从python使用Opencv Cuda功能
我现在非常需要的两个功能是cuda::warpPerspective
和cv::cuda::DescriptorMatcher::knnMatch()
。
我试图通过遵循@ostrumvulpes在Accessing OpenCV CUDA Functions from Python (No PyCUDA)中建议的方法来实现warpPerspective
,并且它工作的很完美。现在我陷入了DescriptorMatcher::knnMatch()
。更确切地说,我需要使用蛮力描述符匹配器knnmatch
函数(CUDA)。我在网上搜索了用C++编写的例子,以便我得到一个初步的想法如何通过cython转换它使其工作。
大部分我发现的例子是类似以下内容:
Ptr<cuda::DescriptorMatcher> matcher =
cuda::DescriptorMatcher::createBFMatcher();
vector< vector< DMatch> > matches;
matcher->knnMatch(descriptors_object_Gpu, descriptors_scene_Gpu, matches, 2);
要实现这三条线我第一次加入了我认为在.pxd文件是必要的。我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)
和我PYX看起来是这样的:
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")
,当我试图编译它,我得到一个错误,说'Ptr[DescriptorMatcher]' has no attribute 'knnMatch'
。
现在据我了解,Ptr是DescriptorMatcher
类型的共享指针,所以在从我的.pxd文件中定义Ptr的方式中肯定有些问题。
我只是不知道如何解决它。如果有人能帮助我解决问题,我将非常感激。
你能否使它工作。你使用的是什么版本的python和opencv? – Alvar