Hi Sergey, That's great and thank you very much. A couple of points I'm not sure of; please let me check with you what I do - it's not quite working. (1) I convert my RGB picture into HSL (this can be done through e.g. GIMP) and export as 3 separate FITS files. (2) I then import the Hue and Saturation fits file into Veusz. (3) I have an image from the Hue file, using the "huevalue" colormap, which is ((255, 0, 0), (255, 255, 0), (0, 255, 0), (0, 255, 255), (0, 0, 255), (255, 0, 255), (255, 0, 0)) (4) I have an image from the Saturation file, using the standard greyscale colormap. (5) Both have a transparency set to 50% - is this correct?
I'm not sure I understand what you mean about greyscale with alpha = (1-C) - what is C? Mark Durré Ph.D. Student Centre for Astrophysics and Supercomputing Swinburne University of Technology PO Box 218, Hawthorn Victoria 3122, Australia Email: mdu...@swin.edu.au On 7/02/16 6:48 AM, "Gromov, Sergey" <sergey.gro...@mpic.de> wrote: >Hi Mark and Jeremy, >Actually, everything is possible with Veusz. Indeed, the RGB components >one may convert into HSL, then plot H using respective colour map, >further covered with L in grayscale with alpha equal (1-C). >See the sample attached, >Hope this helps, >Sergey > > >> -----Original Message----- >> From: Veusz-discuss [mailto:veusz-discuss-boun...@gna.org] On Behalf Of >> Gromov, Sergey >> Sent: 06 February 2016 16:27 >> To: Jeremy Sanders <jer...@jeremysanders.net>; Mark Durre >> <mdu...@swin.edu.au> >> Cc: veusz-discuss@gna.org >> Subject: Re: [Veusz-discuss] Layering of images >> >> Hi Mark and Jeremy, >> >> Could that be a feasible solution? >> 1) Creating a hue-sequence custom colormap >> 2) Calculate hue and saturation values based on R,G,B fields (you can >>use a >> custom function for 2D datasets) >> 3) Show the hue field in image widget with hue colormap, and set >>transparency >> following saturation field. >> >> May I be wrong here? What colour should be graph background for proper >> saturation? >> >> Sergey >> >> >> >> > -----Original Message----- >> > From: Veusz-discuss [mailto:veusz-discuss-boun...@gna.org] On Behalf >> > Of Jeremy Sanders >> > Sent: 06 February 2016 15:28 >> > To: Mark Durre <mdu...@swin.edu.au>; veusz-discuss@gna.org >> > Subject: Re: [Veusz-discuss] Layering of images >> > >> > Hi Mark >> > >> > On 02/01/2016 04:30 AM, Mark Durre wrote: >> > >> > > Perhaps what is needed is to just numerically add the RGB colors >> > > from each layer (obviously clipping at 255), with the user adjusting >> > > the colors by choice of colormap (e.g. blue, green and red, but >> > > could be >> > > others) and the Min/Max values and scaling mode. >> > >> > The layering is currently just what you get with Qt if you use >> > different opacity for the filled regions. It's what you get if you >> > just hold materials with different opacities in front of each other. >> > >> > A more sophisticated image widget with layers could add the layers in >> > different ways (e.g. as RGB components), but this would have to be >> > done within the widget. >> > >> > Cheers >> > >> > Jeremy >> > >> > _______________________________________________ >> > Veusz-discuss mailing list >> > Veusz-discuss@gna.org >> > https://mail.gna.org/listinfo/veusz-discuss >> _______________________________________________ >> Veusz-discuss mailing list >> Veusz-discuss@gna.org >> https://mail.gna.org/listinfo/veusz-discuss _______________________________________________ Veusz-discuss mailing list Veusz-discuss@gna.org https://mail.gna.org/listinfo/veusz-discuss
