OpenCV:Python 接口内存泄漏,但 C 版本没有内存泄漏
我在这里问是因为到目前为止我还没有得到 OpenCV 开发人员的任何帮助。我将问题简化为一个非常简单的测试用例,因此任何具有 CPython 背景的人都可以在这里提供帮助。
这个C代码没有泄漏:
int main() {
while(true) {
int hist_size[] = {40};
float range[] = {0.0f,255.0f};
float* ranges[] = {range};
CvHistogram* hist = cvCreateHist(1, hist_size, CV_HIST_ARRAY, ranges, 1);
cvReleaseHist(&hist);
}
}
这个Python代码确实泄漏:
while True: cv.CreateHist([40], cv.CV_HIST_ARRAY, [[0,255]], 1)
我搜索了CPython代码(OpenCV当前的SVN主干代码)并发现了这个:
struct cvhistogram_t {
PyObject_HEAD
CvHistogram h;
PyObject *bins;
};
从
/* cvhistogram */
static void cvhistogram_dealloc(PyObject *self)
{
cvhistogram_t *cvh = (cvhistogram_t*)self;
Py_DECREF(cvh->bins);
PyObject_Del(self);
}
static PyTypeObject cvhistogram_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0, /*size*/
MODULESTR".cvhistogram", /*name*/
sizeof(cvhistogram_t), /*basicsize*/
};
static PyObject *cvhistogram_getbins(cvhistogram_t *cvh)
{
Py_INCREF(cvh->bins);
return cvh->bins;
}
static PyGetSetDef cvhistogram_getseters[] = {
{(char*)"bins", (getter)cvhistogram_getbins, (setter)NULL, (char*)"bins", NULL},
{NULL} /* Sentinel */
};
static void cvhistogram_specials(void)
{
cvhistogram_Type.tp_dealloc = cvhistogram_dealloc;
cvhistogram_Type.tp_getset = cvhistogram_getseters;
}
……
static PyObject *pycvCreateHist(PyObject *self, PyObject *args, PyObject *kw)
{
const char *keywords[] = { "dims", "type", "ranges", "uniform", NULL };
PyObject *dims;
int type;
float **ranges = NULL;
int uniform = 1;
if (!PyArg_ParseTupleAndKeywords(args, kw, "Oi|O&i", (char**)keywords, &dims, &type, convert_to_floatPTRPTR, (void*)&ranges, &uniform)) {
return NULL;
}
cvhistogram_t *h = PyObject_NEW(cvhistogram_t, &cvhistogram_Type);
args = Py_BuildValue("Oi", dims, CV_32FC1);
h->bins = pycvCreateMatND(self, args);
Py_DECREF(args);
if (h->bins == NULL) {
return NULL;
}
h->h.type = CV_HIST_MAGIC_VAL;
if (!convert_to_CvArr(h->bins, &(h->h.bins), "bins"))
return NULL;
ERRWRAP(cvSetHistBinRanges(&(h->h), ranges, uniform));
return (PyObject*)h;
}
OpenCV C标头中:
typedef struct CvHistogram
{
int type;
CvArr* bins;
float thresh[CV_MAX_DIM][2]; /* For uniform histograms. */
float** thresh2; /* For non-uniform histograms. */
CvMatND mat; /* Embedded matrix header for array histograms. */
}
CvHistogram;
我不太明白一切都是因为我以前从未使用过 Python 的 C 接口。但我正在寻找的错误可能就在这段代码中的某个地方。
我说得对吗?或者我应该在哪里寻找该错误?我该如何解决它?
(看过这个问题早期版本的人请注意:我查看了错误的代码。他们的 SWIG 接口已被弃用并且不再使用(但代码仍然存在于 SVN 中,这就是我混淆它的原因。所以不要'不要查看 interfaces/swig
,此代码是旧的且未使用。当前代码位于 modules/python
中。
) ros.org/trac/opencv/ticket/674">上游错误报告:OpenCV Python CreateHist 中的 memleak
I am asking here because I haven't gotten any help from the OpenCV developers so far. I reduced the problem to a very simple test case so probably anyone with some background with CPython could help here.
This C code does not leak:
int main() {
while(true) {
int hist_size[] = {40};
float range[] = {0.0f,255.0f};
float* ranges[] = {range};
CvHistogram* hist = cvCreateHist(1, hist_size, CV_HIST_ARRAY, ranges, 1);
cvReleaseHist(&hist);
}
}
This Python code does leak:
while True: cv.CreateHist([40], cv.CV_HIST_ARRAY, [[0,255]], 1)
I searched through the CPython code (of OpenCVs current SVN trunk code) and found this:
struct cvhistogram_t {
PyObject_HEAD
CvHistogram h;
PyObject *bins;
};
...
/* cvhistogram */
static void cvhistogram_dealloc(PyObject *self)
{
cvhistogram_t *cvh = (cvhistogram_t*)self;
Py_DECREF(cvh->bins);
PyObject_Del(self);
}
static PyTypeObject cvhistogram_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0, /*size*/
MODULESTR".cvhistogram", /*name*/
sizeof(cvhistogram_t), /*basicsize*/
};
static PyObject *cvhistogram_getbins(cvhistogram_t *cvh)
{
Py_INCREF(cvh->bins);
return cvh->bins;
}
static PyGetSetDef cvhistogram_getseters[] = {
{(char*)"bins", (getter)cvhistogram_getbins, (setter)NULL, (char*)"bins", NULL},
{NULL} /* Sentinel */
};
static void cvhistogram_specials(void)
{
cvhistogram_Type.tp_dealloc = cvhistogram_dealloc;
cvhistogram_Type.tp_getset = cvhistogram_getseters;
}
...
static PyObject *pycvCreateHist(PyObject *self, PyObject *args, PyObject *kw)
{
const char *keywords[] = { "dims", "type", "ranges", "uniform", NULL };
PyObject *dims;
int type;
float **ranges = NULL;
int uniform = 1;
if (!PyArg_ParseTupleAndKeywords(args, kw, "Oi|O&i", (char**)keywords, &dims, &type, convert_to_floatPTRPTR, (void*)&ranges, &uniform)) {
return NULL;
}
cvhistogram_t *h = PyObject_NEW(cvhistogram_t, &cvhistogram_Type);
args = Py_BuildValue("Oi", dims, CV_32FC1);
h->bins = pycvCreateMatND(self, args);
Py_DECREF(args);
if (h->bins == NULL) {
return NULL;
}
h->h.type = CV_HIST_MAGIC_VAL;
if (!convert_to_CvArr(h->bins, &(h->h.bins), "bins"))
return NULL;
ERRWRAP(cvSetHistBinRanges(&(h->h), ranges, uniform));
return (PyObject*)h;
}
And from the OpenCV C headers:
typedef struct CvHistogram
{
int type;
CvArr* bins;
float thresh[CV_MAX_DIM][2]; /* For uniform histograms. */
float** thresh2; /* For non-uniform histograms. */
CvMatND mat; /* Embedded matrix header for array histograms. */
}
CvHistogram;
I don't exactly understand everything because I never worked with the C-interface to Python before. But probably the bug I am searching for is somewhere in this code.
Am I right? Or where should I search for the bug? How would I fix it?
(Note for people who have seen an earlier version of this question: I looked at the wrong code. Their SWIG interface was deprecated and not used anymore (but the code was still there in SVN, this is why I confused it. So don't look into interfaces/swig
, this code is old and not used. The current code lives in modules/python
.)
如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱,如果其他用户或者作者回复了您的评论,将不能在第一时间通知您!
发布评论
评论(2)
它已被修复。
It has been fixed.
我认为你有垃圾收集问题,因为你永远不会离开循环。
这是否比预期更有效?
I think you have garbage collection issue, in that you never leave the loop.
Does this work more as expected?