Search found 45 matches

by gubach
2017-02-15T02:06:26-07:00
Forum: Users
Topic: morphology operation that generate an additional compact border region around shapes
Replies: 21
Views: 9827

Re: morphology operation that generate an additional compact border region around shapes

About the management of complex functions: In Matlab each complex function has its own m-file like conformalInverse_0001.h: function U = conformalInverse(X, ~) %#codegen U = [zeros(size(X))]; Z = complex(X(:,1),X(:,2)); % insert CM formula here a = 2; W = (1./(4 * Z.^a - 1)); % bipole 1/(4*z^2-1) U(...
by gubach
2017-02-14T05:16:31-07:00
Forum: Users
Topic: morphology operation that generate an additional compact border region around shapes
Replies: 21
Views: 9827

Re: morphology operation that generate an additional compact border region around shapes

@fmw42: Have taken a look at the CM image examples: Very!!!! interesting because of -v vp ... VP is the virtual-pixel method. Any virtual-pixel method is allowed. The default=tile. It seems that a virtual-pixel method can avoid the empty black spaces that I am trying to fight with those post process...
by gubach
2017-02-14T02:27:01-07:00
Forum: Users
Topic: morphology operation that generate an additional compact border region around shapes
Replies: 21
Views: 9827

Re: morphology operation that generate an additional compact border region around shapes

@fmw42: I am in the experimental and development phase; I have used for the published images the bipole CM a = 2; W = (1./(4*Z.^a - 1)); extracted from https://karczmarczuk.users.greyc.fr/TEACH/InfoGeo/Work/ComplexMapStill.jar I will look at the script and your proposal with -level soon. Thank you v...
by gubach
2017-02-13T12:50:43-07:00
Forum: Users
Topic: morphology operation that generate an additional compact border region around shapes
Replies: 21
Views: 9827

Re: morphology operation that generate an additional compact border region around shapes

@ snibgo: the pictures were generated by conformal maps (a sub set of complex functions) for image distortion programmed in Matlab. IMs fx can not handle complex numbers so I had to look for an other environment. But now I have the problem that I can not duplicate the CopyOpacity+Over pipeline from ...
by gubach
2017-02-13T05:20:26-07:00
Forum: Users
Topic: morphology operation that generate an additional compact border region around shapes
Replies: 21
Views: 9827

morphology operation that generate an additional compact border region around shapes

I have a gray scale mask (https://www.flickr.com/photos/gbachelier/32061262473/in/dateposted-public/) that should be used in CopyOpacity to mask out regions with strong aliased edges (https://www.flickr.com/photos/gbachelier/albums/72157677436918822). My idea was to enlarge the black shapes of the m...
by gubach
2017-01-16T05:39:09-07:00
Forum: Developers
Topic: Mitchell interpolation definition
Replies: 3
Views: 8771

Re: Mitchell interpolation definition

Thanks snibgo and fmw42! Found this in resize.c and http://http.developer.nvidia.com/GPUGems/gpugems_ch24.html : static double CubicBC(const double x,const ResizeFilter *resize_filter) { /* Cubic Filters using B,C determined values: Mitchell-Netravali B = 1/3 C = 1/3 "Balanced" cubic spline filter C...
by gubach
2017-01-13T09:26:23-07:00
Forum: Developers
Topic: Mitchell interpolation definition
Replies: 3
Views: 8771

Mitchell interpolation definition

Hello, I want to define the Mitchell function as a custom interpolation kernel in Matlabs imresize (examples in http://stackoverflow.com/questions/8036019/matlab-imresize-with-a-custom-interpolation-kernel). First step would be the definition of the Mitchel filter and in http://www.imagemagick.org/U...
by gubach
2016-05-09T11:53:51-07:00
Forum: Developers
Topic: image distortion with conformal maps
Replies: 2
Views: 4898

image distortion with conformal maps

In several occasions I stumbled upon the possibility to distort images with conformal maps (for example with SeamlessMaker http://www.hypatiasoft.fr/) and I experimented with http://davidbau.com/conformal/ to get maps that might be interesting for distortion. Is fx expressive enough to define confor...
by gubach
2016-04-25T02:19:21-07:00
Forum: Developers
Topic: list of coordinates of the pixels of a line between 2 pixels
Replies: 3
Views: 5079

Re: list of coordinates of the pixels of a line between 2 pixels

thank you for answering! @fmw42 "txt:- | grep "white"" was helpful; it works but I have to write each time an intermediate image because I can't again port the syntax to PerlMagick (@list=$img->Get(?)). I have also improved the linear equation approach which takes some distinction of cases. The Blac...
by gubach
2016-04-19T14:47:15-07:00
Forum: Developers
Topic: list of coordinates of the pixels of a line between 2 pixels
Replies: 3
Views: 5079

list of coordinates of the pixels of a line between 2 pixels

Is there an internal way in IM to get the sorted list of coordinates of the pixels of a line (pointsize = 1) between two given pixels? I have tried some analytical ways with the linear equation but if the absolute value of the slope is not 1 I get too many or too little pixels if I draw the resultin...
by gubach
2016-03-26T03:26:20-07:00
Forum: PerlMagick
Topic: PM Distort syntax for Arc
Replies: 1
Views: 8299

Re: PM Distort syntax for Arc

Please help with the PM syntax because writing an intermediate png costs a lot of time in my huge batch runs. I cant find any PM arc examples on Google. Thank you very much!
by gubach
2016-03-23T05:52:10-07:00
Forum: PerlMagick
Topic: PM Distort syntax for Arc
Replies: 1
Views: 8299

PM Distort syntax for Arc

After it was clarifyed that Arc and Polar are available via PM the question how to translate the command line syntax remains. Here examples for the simplified and complete Arc syntax: a) Arc with simplified syntax command line: convert input.png -virtual-pixel HorizontalTile -background black -disto...
by gubach
2016-03-16T06:52:11-07:00
Forum: PerlMagick
Topic: Distort methods Arc and Polar not in PM?
Replies: 1
Views: 7963

Distort methods Arc and Polar not in PM?

In the list of Distort methods (1) Arc and Polar are not included, so one could conclude those methods are not available in PerlMagick. Why?

(1) method=>{Affine, AffineProjection, Bilinear, Perspective, Resize, ScaleRotateTranslate}
by gubach
2016-02-22T16:08:59-07:00
Forum: Developers
Topic: Arc 360 radius as function of input image w x h
Replies: 5
Views: 4392

Re: Arc 360 radius as function of input image w x h

thank you for clarifying the 2*pi. > What version IM are you using? For some reasons I am using an old development environment with ImageMagick 6.6.2-5 2010-08-12 Q8 > I haven't traced the code to find where 1530.739 becomes 1532. On http://www.imagemagick.org/Usage/distorts there is a hint about an...
by gubach
2016-02-22T09:37:57-07:00
Forum: Developers
Topic: Arc 360 radius as function of input image w x h
Replies: 5
Views: 4392

Re: Arc 360 radius as function of input image w x h

thank you for answering; I am puzzling what 2.pi might be? 2*pi?
In an example I just made with Arc 360 (in: w=3740 x h=1872 out: r=1452) the term 2.pi becomes 7.241... so a bit more than 2*pi