[Chennaipy] Mutli- threading in cython

Sat Jun 2 03:31:58 EDT 2018

Hi,

Use the version of code that is mentioned in your NOTE 4.

But why are you keeping np.dtype('<'B)  instead of  np.dtype('<'H') ? in

data[i,:,:] = PyArray_NewFromDescr(<PyTypeObject *> np.ndarray,
np.dtype('<B'), 2,dims, strides,pBuf, np.NPY_C_CONTIGUOUS,     None)

and change this too.
npstrides[1] = 2 #short is two bytes long.

Regards,
Aravindhan K

On Fri, Jun 1, 2018 at 4:32 PM, aishwarya selvaraj <
aishwaryaselvaraj1708 at gmail.com> wrote:

> Hi,
> I tried the changes. No was not able to solve my issue. I'm attaching the
> file. Kindly take a look at it.
>
> ᐧ
>
> On Mon, May 28, 2018 at 10:21 PM, Aravindhan K <aravindhank1994 at gmail.com>
> wrote:
>
>> Hi,
>>
>> See the comments starts with NOTE in the attached file.
>> Hope that may guide you find the issue.
>>
>> Regards,
>> Araindhan K
>>
>> On Mon, May 28, 2018 at 11:35 AM, aishwarya selvaraj <
>> aishwaryaselvaraj1708 at gmail.com> wrote:
>>
>>> Hi,
>>> Yes, I was able to make use of  PyArray_NewFromDescr in my code.
>>> Storing into a 3D array has now become a lot faster. Thank you!But the
>>> CCD images stored using this method looks quite different from the ones
>>> acquired earlier.
>>> In the older method at the end of for loop, there is incrementing using
>>>  _puc_image += aoiStride, I'm not very sure on how to do it with new
>>> method. Could you please take a look at it?
>>> ᐧ
>>>
>>> On Mon, May 28, 2018 at 11:17 AM, aishwarya selvaraj <
>>> aishwaryaselvaraj1708 at gmail.com> wrote:
>>>
>>>> Hi,
>>>> Yes, I was able to make use of  PyArray_NewFromDescr in my code.
>>>> Storing into a 3D array has now become a lot faster. Thank you!But the
>>>> CCD images stored using this method looks quite different from the ones
>>>> acquired earlier.
>>>> In the older method at the end of for loop there is incrementing using  _puc_image
>>>> += aoiStride, I'm not very sure on how to do it with new method. Could
>>>> you please take a look at it? I'm not very sure what am I missing here.
>>>> ᐧ
>>>>
>>>>>
>>>>>> dims[0] = self.aoiWidth
>>>>>
>>>>> dims[1] = self.aoiHeight
>>>>>
>>>>>                         #method 1
>>>>>
>>>>> data[i,:,:] = PyArray_NewFromDescr(<PyTypeObject *> np.ndarray,
>>>>>> np.dtype('<B'), 2,dims, NULL,pBuf, np.NPY_C_CONTIGUOUS, None)
>>>>>
>>>>> #-----------------------------------------------------------
>>>>>> ------------------------------------------------
>>>>>
>>>>> #method 2:
>>>>>
>>>>> #if (i==0) or (i == 1) or (i ==2) or (i==3) or (i==4):
>>>>>
>>>>> #_puc_image = pBuf
>>>>>
>>>>> #pus_image = <unsigned short*>pBuf
>>>>>
>>>>> #for j in range(self.aoiWidth/self.hbin):
>>>>>
>>>>> #pus_image = <unsigned short*>(_puc_image)
>>>>>
>>>>> #for k in range(self.aoiHeight/self.vbin):
>>>>>
>>>>> #data[l][j][k]  = pus_image[0]
>>>>>
>>>>> #pus_image += 1
>>>>>
>>>>> #_puc_image += aoiStride
>>>>>
>>>>> #l = l+1
>>>>>
>>>>> the image displayed using method 1 is very different from method 1.
>>>>
>>>> ᐧ
>>>>
>>>> On Thu, May 24, 2018 at 9:34 AM, aishwarya selvaraj <
>>>> aishwaryaselvaraj1708 at gmail.com> wrote:
>>>>
>>>>> Hi, Yes I was able to make use of  PyArray_NewFromDescr in my code.
>>>>> Storing into a 3D array has now become a lot faster.Thank you!
>>>>> But the CCD images stored using this method looks quite different from
>>>>> the ones acquired earlier. I'm yet to find the root of the problem for the
>>>>> same. Could you please take a look at it? I'm not very sure what am I
>>>>> missing here.
>>>>> ᐧ
>>>>>
>>>>> On Wed, May 23, 2018 at 7:43 AM, Aravindhan K <
>>>>> aravindhank1994 at gmail.com> wrote:
>>>>>
>>>>>> Hi,
>>>>>> Please use this example code. https://pastebin.com/nh9rvqfm.
>>>>>> I have used this link as a reference.
>>>>>> https://groups.google.com/forum/#!topic/cython-users/fFBiCCwblD0
>>>>>>
>>>>>>
>>>>>> Regards,
>>>>>> Aravindhan K
>>>>>>
>>>>>> On Tue, May 22, 2018 at 11:58 AM, aishwarya selvaraj <
>>>>>> aishwaryaselvaraj1708 at gmail.com> wrote:
>>>>>>
>>>>>>> Hi,
>>>>>>> Thank you for the suggestion. I was trying out an example code
>>>>>>> using  PyArray_NewFromDescr*.* PFA of the code.I compiled the file
>>>>>>> using :python setup.py build_ext --inplace.
>>>>>>> When compiled I get the following error :
>>>>>>> fatal error : numpy/arrayobject.h :No such file or directory.
>>>>>>> I would be realy gratefull if you could do the edit in the file I
>>>>>>> sent in my first mail.
>>>>>>>
>>>>>>> ᐧ
>>>>>>>
>>>>>>> On Mon, May 21, 2018 at 9:19 PM, Aravindhan K <
>>>>>>> aravindhank1994 at gmail.com> wrote:
>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> You could try using PyArray_NewFromDescr NumPy C-API function for
>>>>>>>> creating nd-array
>>>>>>>> in function capturing frames.
>>>>>>>> than doing nested loops to do copy byte by byte. (This could be the
>>>>>>>> bottleneck)
>>>>>>>> https://docs.scipy.org/doc/numpy-1.14.0/reference/c-api.arra
>>>>>>>> y.html#from-scratch
>>>>>>>>
>>>>>>>>
>>>>>>>> Regards,
>>>>>>>> Aravindhan K
>>>>>>>>
>>>>>>>> On Mon, May 21, 2018 at 5:12 PM, aishwarya selvaraj <
>>>>>>>> aishwaryaselvaraj1708 at gmail.com> wrote:
>>>>>>>>
>>>>>>>>> Dear all,
>>>>>>>>> I was programming for Andor CCD using SDK libraries in python
>>>>>>>>> using cython.
>>>>>>>>> I have a piece of code within my .pyx script which does the
>>>>>>>>> function of storing the data into a 3D array. While acquiring n frames,
>>>>>>>>> each of them is stored in a 3D array named data, which later I would be
>>>>>>>>> displaying. But this creates a bottleneck in my code.
>>>>>>>>> Hence I need to introduce threading, such that for each frame to
>>>>>>>>> be stored there are individual threads for the same and the frames could be
>>>>>>>>> displayed simultaneously without creating a performance lag.
>>>>>>>>> Since I have never worked on multithreading, could anyone please
>>>>>>>>> help me.
>>>>>>>>> PFA of the code. (LiveAcquisition code)
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> --
>>>>>>>>> Regards,
>>>>>>>>> Aishwarya Selvaraj
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Chennaipy mailing list
>>>>>>>>> Chennaipy at python.org
>>>>>>>>> https://mail.python.org/mailman/listinfo/chennaipy
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> Chennaipy mailing list
>>>>>>>> Chennaipy at python.org
>>>>>>>> https://mail.python.org/mailman/listinfo/chennaipy
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Regards,
>>>>>>> Aishwarya Selvaraj
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Chennaipy mailing list
>>>>>>> Chennaipy at python.org
>>>>>>> https://mail.python.org/mailman/listinfo/chennaipy
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Chennaipy mailing list
>>>>>> Chennaipy at python.org
>>>>>> https://mail.python.org/mailman/listinfo/chennaipy
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Regards,
>>>>> Aishwarya Selvaraj
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Regards,
>>>> Aishwarya Selvaraj
>>>>
>>>
>>>
>>>
>>> --
>>> Regards,
>>> Aishwarya Selvaraj
>>>
>>> _______________________________________________
>>> Chennaipy mailing list
>>> Chennaipy at python.org
>>> https://mail.python.org/mailman/listinfo/chennaipy
>>>
>>>
>>
>> _______________________________________________
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>> Chennaipy at python.org
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>>
>>
>
>
> --
> Regards,
> Aishwarya Selvaraj
>
> _______________________________________________
> Chennaipy mailing list
> Chennaipy at python.org
> https://mail.python.org/mailman/listinfo/chennaipy
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>
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