Mailman 3 October 2013 - scikit-image

Re: skimage and opencv
by Emmanuelle Gouillart Sept. 22, 2016

Sept. 22, 2016

Hi FranÃ¯Â¿Â½ois, that's an excellent question, and not a troll :-). Opencv is a very powerful library, but it focuses primarily on computer vision (feature detection and extraction, classification, ...), as opposed to image processing in general (with other tasks such as denoising, segmentation, ...). The other big difference is that skimage builds on numpy ndarrays, and uses the full power of the numpy API (including of course the basic facilities for processing arrays as images that come with numpy), as well as some of scipy functions (you could have added scipy.ndimage to your list -- a few functions in skimage are wrappers around scipy.ndimage, that exist for the sake of completeneness). One important consequence is that algorithms working for 3-d or even n-d images can be easily implemented in 3-d/n-d in skimage, whereas opencv is restricted to 2-D images (as far as I know). Thanks to the use of numpy arrays, the API of skimage is also quite pleasant for a numpy user, more than the API of opencv. A related difference is that skimage is written in python and cython, whereas opencv is a C++ library. The two libraries attract a different crowd of developers, and a Python/Cython toolkit based on numpy arrays is easier to develop and maintain inside the Scientific Python ecosystem. I'm sure that other devs/users will have things to add to this discussion! Cheers, Emmanuelle On Thu, Dec 27, 2012 at 02:06:08PM -0800, FranÃ¯Â¿Â½ois wrote: > Hi users and devs, > It came to my knowledge that another python library (based on C++ and C > codes) for image processing exists too : opencv > I understand that numpy intregrates some basic features and we need some > advanced features but I have the feeling that skimages is redoundant with > opencv in some ways. > What's the position of skimage about that? (Don't read this question as a > troll but like a real question). > I mean that similar features exist in both. Would not be possible to > reuse/integrate opencv or merge? what's the reason for keeping them apart? > My observation is there is 4 libraries to manipulate images: > * PIL > * numpy > * skimages > * opencv > That's a lot. > Cheers,

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Re: Contribution: circles and hough transform
by François June 18, 2014

June 18, 2014

Hi, FYI, I plan to work on the detection of ellipses quite soon. Stefan indicated to me a reference which seems fairly simple to implement. Cheers, François.

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Kakadu JP2000 reader
by Michael Aye Nov. 25, 2013

Nov. 25, 2013

Hi! I was wondering if it would be possible to implement the Kakadu JP2000 reader into scikit-image? I believe but am not sure that the reader only could be used without licensing fees? At least it's worth investigating because that reader is really the most powerful JP2000 reader out there and the only one that can deal with the large HiRISE images of the MRO spacecraft. Failing the above, a work-around could be to implement or encapsulate system calls to the freely downloadable kdu-expand utilities, converting it to something that is compatible with your current import routines? Best regards, Michael

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Re: Returning an image from the viewer
by Josh Warner Oct. 29, 2013

Oct. 29, 2013

There was some discussion about the save functionality in the original PR. I admit, I advocated to change "File -> Save As" from saving the overlay to saving the actual image the user sees... so feel free to send some blame for the present behavior my way. There should be an option to add a Save Overlay *button* which should allow you to grab the overlay specifically. As to your second question: I think you can send data either to a file, or to a buffer which can be read out using `skimage.io.pop`. I've used this before, but my memory is a bit fuzzy on it now. If this isn't currently available for scripting like your hoped-for functionality example, I'm sure it could be implemented. Thanks for the PR fixing the save dialog if it's RGB! On Monday, October 28, 2013 2:19:03 AM UTC-5, Juan Nunez-Iglesias wrote: > > Hi all, but especially @tonysyu: > > I'm using the viewer for the first time to add some interactivity to my > work. Please forgive the noobish-ness: I've only ever worked on > command-line stuff. (Thanks btw to @tonysyu for his awesome SciPy lightning > talk, which inspired me to even dip my toes in this!) > > I'm running an RGB image through a bunch of thresholding and morphological > operations, and I want to fiddle with the parameters before getting back > the filter output. I'm running into the following problems: > > 1) The file > save as dialog saves a composite image of the overlay and > underlying image, where I just want the overlay. > 2) The file > save as dialog actually crashes when the underlying image is > RGB! (PR forthcoming) > 3) But most of all, I don't actually want to save the overlay, I just want > to return it to the calling process. How would one go about this? Here's my > code now: > > v = viewer.ImageViewer(rgbs[0]) > v += CentroPlugin() > v.show() > > > which works as expected. I'd like something like: > > v = viewer.ImageViewer(rgbs[0]) > v += CentroPlugin() > overlay = v.show() > > Is this possible? > > Thanks, > > Juan. >

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Returning an image from the viewer
by Juan Nunez-Iglesias Oct. 28, 2013

Oct. 28, 2013

Hi all, but especially @tonysyu: I'm using the viewer for the first time to add some interactivity to my work. Please forgive the noobish-ness: I've only ever worked on command-line stuff. (Thanks btw to @tonysyu for his awesome SciPy lightning talk, which inspired me to even dip my toes in this!) I'm running an RGB image through a bunch of thresholding and morphological operations, and I want to fiddle with the parameters before getting back the filter output. I'm running into the following problems: 1) The file > save as dialog saves a composite image of the overlay and underlying image, where I just want the overlay. 2) The file > save as dialog actually crashes when the underlying image is RGB! (PR forthcoming) 3) But most of all, I don't actually want to save the overlay, I just want to return it to the calling process. How would one go about this? Here's my code now: v = viewer.ImageViewer(rgbs[0]) v += CentroPlugin() v.show() which works as expected. I'd like something like: v = viewer.ImageViewer(rgbs[0]) v += CentroPlugin() overlay = v.show() Is this possible? Thanks, Juan.

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Re: CIELUV Transformations
by Stéfan van der Walt Oct. 27, 2013

Oct. 27, 2013

On Wed, Oct 23, 2013 at 5:56 PM, Jaime Fernández del Río <jaime.frio(a)gmail.com> wrote: > So, who's up for coding CIECAM02 color transformations, whatever that may > be? ;-) Let's see. We need someone who understands the intricacies of color spaces. Now who could that be? Thank you in advance! Stéfan

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Re: Clarity
by Juan Nunez-Iglesias Oct. 27, 2013

Oct. 27, 2013

On Sat, Oct 26, 2013 at 4:05 AM, Stéfan van der Walt <stefan(a)sun.ac.za>wrote: > A little bit tongue in cheek: > > > http://nbviewer.ipython.org/urls/gist.github.com/stefanv/7158075/raw/041808… > Awesome! =)

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Re: Release time
by Johannes Schönberger Oct. 27, 2013

Oct. 27, 2013

Updated to 0.9.3 with a small bugfix. https://pypi.python.org/pypi/scikit-image Am 19.10.2013 um 14:34 schrieb Stéfan van der Walt <stefan(a)sun.ac.za>: > On Sat, Oct 19, 2013 at 12:37 PM, Ankit Agrawal <aaaagrawal(a)gmail.com> wrote: >> Any updates about the 0.9 release? > > Just waiting for GitHub to come back online to push the tags. > > Stéfan > > -- > You received this message because you are subscribed to the Google Groups "scikit-image" group. > To unsubscribe from this group and stop receiving emails from it, send an email to scikit-image+unsubscribe(a)googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. >

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Re: Clarity
by Norman Vine Oct. 26, 2013

Oct. 26, 2013

On Oct 24, 2013, at 2:27 AM, Juan Nunez-Iglesias <jni.soma(a)gmail.com> wrote: > Hi guys, > > Does anyone here have any ideas about what the Camera+ Clarity filter is doing? Some examples of the filter here and here. > > Might be a nice addition to skimage.exposure... =) > > Juan. > see http://code.google.com/p/imagestack/wiki/locallaplacian

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Re: import error on linux
by Neil Oct. 26, 2013

Oct. 26, 2013

Good idea - using transform.AffineTransform is much nicer. Updated. Thanks, yes, it was a really fun project. I've always been on the software side, but there's a huge maker/DIY movement going on in hardware/electronics at the moment. Lots of cool opportunities for embedded image processing & computer vision applications. On Friday, 25 October 2013 17:35:10 UTC+1, Stefan van der Walt wrote: > > On Fri, Oct 25, 2013 at 3:37 PM, Neil <yager...(a)gmail.com <javascript:>> > wrote: > > I'm a little late on this, but I've just used scikit-image with a > Raspberry > > Pi project, and I can confirm that everything works fine. I included a > > little installation recipe on the project page: > > > > http://www.aicbt.com/disguise-detection/#program > > What a fun project! You could perhaps even use skimage.transform to > help with the calibration. > > Stéfan >

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