calcHist has wrong documetation?

[info gabor]

I had some difficulties with the calcHist interface, using the one given in the API documentation:

calcHist( (object)images, (Mat)channels, (Mat)mask, (SparseMat)hist, (Mat)histSize, (object)ranges [, (bool)uniform=True [, (bool)accumulate=False]]) -> None :

with, e.g. 

    Argument 'images':

        C/C++ type: ::cv::Mat const *.

        Python type: list of MatND, e.g. [MatND(), MatND(), MatND()].

Following the error report of Python I got it working. Example follows:

Starting with some single-chanel image img0 and a corresponding mask msk0

    imgs=cv.vector_Mat()

    imgs.append(img0)

    channels=cv.vector_int()

    channels.append(0)

    mask=msk

    hist=cv.MatND()

    histSize=cv.vector_int()

    histSize.append(255)

    f=cv.vector_float32()

    f.append(0.)

    f.append(255.)

    ranges=cv.vector_vector_float32()

    ranges.append(f)

    cv.calcHist(imgs,channels,mask,hist,histSize,ranges)

[Minh-Tri Pham]

The API documentation on the web has not been updated, sorry. The docstring
of each function is, however, always up to date. :)

Cheers,
Minh-Tri

On 29/07/2010 08:11, info gabor wrote:
> I had some difficulties with the calcHist interface, using the one given in
> the API documentation:
>

> /calcHist( (object)images, (Mat)channels, (Mat)mask, (SparseMat)hist,

> (Mat)histSize, (object)ranges [, (bool)uniform=True [,

> (bool)accumulate=False]]) -> None :/
>
> with, e.g.
> / Argument 'images':/
> / C/C++ type: ::cv::Mat const *./
> / Python type: list of MatND, e.g. [MatND(), MatND(), MatND()]./

>
> Following the error report of Python I got it working. Example follows:
> Starting with some single-chanel image img0 and a corresponding mask msk0
>

> / imgs=cv.vector_Mat()/
> / imgs.append(img0)/
> / channels=cv.vector_int()/
> / channels.append(0)/
> / mask=msk/
> / hist=cv.MatND()/
> / histSize=cv.vector_int()/
> / histSize.append(255)/
> / f=cv.vector_float32()/
> / f.append(0.)/
> / f.append(255.)/
> / ranges=cv.vector_vector_float32()/
> / ranges.append(f)/
> /
> /
> / cv.calcHist(imgs,channels,mask,hist,histSize,ranges)/
>
>
>
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--
Dr. Minh-Tri Pham
Research Fellow, University of Surrey, UK
Email: t.p...@surrey.ac.uk or pmt...@gmail.com
Mob: +44 (0) 778 774 1089 | Tel: +44 (0) 148 368 4711

[info gabor]

I mixed up 2 inconsistencies, of the API doc and of the docstring. 

The wrong interface I reported came actually from the docstring. 

Minh-Tri, allow me to use this opportunity and thank you for your fantastic code. 

Today I needed the cvBlob library (which is not implemented yet in pyopencv). I had to resort to C++ opencv after few months of being spoiled by your pyopencv. I dearly missed it ! 

Thanks alot!