Hi Harrissou is there any description / documentation of the work that has been done on this (feature description, etc.)? If yes, I'd like to have a look and maybe
Thanks a lot! Stéphane Le mardi 10 janvier 2017, DelazJ <[email protected]> a écrit : > Hi Stéphane, > > 2017-01-10 4:02 GMT+01:00 Stéphane Henriod <[email protected] > <javascript:_e(%7B%7D,'cvml','[email protected]');>>: > >> Hi Chris >> >> this is very nice! I indeed didn't know this trick and will certainly use >> it again in the future! >> >> However... :-) >> >> I am currently teaching QGIS to beginners and this for sure is not an >> appropriate method for them (especially in the case you have to generate >> the symbology file through a script)! >> >> Since the user can style continuous rasters with some "button-clicking", >> I believe the same option should be available for discrete rasters as well. >> >> I am thus wondering if anyone else than me sees it as a priority for >> QGIS? If yes, how to motivate the developers to take it for the next >> release and / or how much would such a development cost? (I unfortunately >> don't have the competences to do it myself) >> >> There have been some work done in the raster properties dialog in the > upcoming 3.0. I don't know if your concern was covered though. > If you want, you can move the question to the developer's list > <http://qgis.org/en/site/getinvolved/mailinglists.html#qgis-developers-list> > and discuss whether/how this can be implemented (and its requirements). > > Regards, > Harrissou > > Thanks again and cheers! >> >> Stéphane >> >> >> Le mardi 10 janvier 2017, Chris House <[email protected] >> <javascript:_e(%7B%7D,'cvml','[email protected]');>> a écrit : >> >>> Hi Stéphane, >>> >>> I don't know if this is what you are looking for or not but I have a >>> method of classifying rasters by color based on a set (standard) colors. I >>> created a spreadsheet that has several required columns, value, red, green, >>> blue...and you can have an optional field for a display value. So say >>> value 1 is water you can use that last column to name that value so that in >>> the QGIS layer tree and in legend it says Water instead of value 1. >>> >>> save the spreadsheet as a csv and change the extension to .txt instead >>> of .csv. >>> >>> I then go into the symbology section of the raster choose singleband >>> pseudocolor. Use the folder to browse to your text file and click add. >>> There is a format for this text file. It is below. If you need me to >>> email it I will do that in direct email. >>> >>> # QGIS Generated Color Map Export File >>> INTERPOLATION:EXACT >>> -9999,0,0,0,255,NoData >>> 0,176,176,176,255,Non-Forested >>> 15,234,255,191,255,10 <= CC < 20 >>> 25,187,230,149,255,20 <= CC < 30 >>> 35,140,201,109,255,30 <= CC < 40 >>> 45,98,176,74,255,40 <= CC < 50 >>> 55,59,153,43,255,50 <= CC < 60 >>> 65,0,128,0,255,60 <= CC < 70 >>> 75,15,92,11,255,70 <= CC < 80 >>> 85,17,61,12,255,80 <= CC < 90 >>> 95,16,36,12,255,90 <= CC <= 100 >>> >>> In my example if I don't assign a value it gets ignored by QGIS. If you >>> are wondering how to assign unique colors to say 200 unique values...just >>> script it. I have done this and as long as you have the number of unique >>> values you want and to make them unique in the script it works. >>> >>> I hope this helps. I know it isn't a "button" but to be honest I like >>> this better. If you already knew this...well then maybe it will help >>> someone out in the future. >>> >>> --Chris >>> >>> On Mon, Jan 9, 2017 at 3:00 PM, <[email protected]> >>> wrote: >>> >>>> Send Qgis-user mailing list submissions to >>>> [email protected] >>>> >>>> To subscribe or unsubscribe via the World Wide Web, visit >>>> http://lists.osgeo.org/mailman/listinfo/qgis-user >>>> or, via email, send a message with subject or body 'help' to >>>> [email protected] >>>> >>>> You can reach the person managing the list at >>>> [email protected] >>>> >>>> When replying, please edit your Subject line so it is more specific >>>> than "Re: Contents of Qgis-user digest..." >>>> >>>> >>>> Today's Topics: >>>> >>>> 1. Re: Symbolizing a discrete or a boolean raster (Stéphane Henriod) >>>> >>>> >>>> ---------------------------------------------------------------------- >>>> >>>> Message: 1 >>>> Date: Mon, 9 Jan 2017 23:07:36 +0600 >>>> From: Stéphane Henriod <[email protected]> >>>> To: Enrico Fiore <[email protected]> >>>> Cc: qgis-user <[email protected]> >>>> Subject: Re: [Qgis-user] Symbolizing a discrete or a boolean raster >>>> Message-ID: >>>> <[email protected] >>>> ail.com> >>>> Content-Type: text/plain; charset="utf-8" >>>> >>>> Hi >>>> >>>> thanks for following up! >>>> >>>> It actually does part of the job! >>>> >>>> Using *Color interpretation: Exact*, I can indeed input the exact >>>> values I >>>> want to display (1,5 and 10) and all other pixels are hidden. >>>> >>>> HOWEVER, >>>> >>>> this still feels like a workaround: >>>> >>>> - In the case of a discrete raster with many (> 50) unique values, I >>>> do >>>> not want to input all of them manually >>>> - In some cases, I do not know in advance all the unique values of my >>>> raster >>>> - If I click on *Classify*, QGIS will choose X values (based on the >>>> number of classes and the classification method (continuous or equal >>>> interval)), which no longer match the "exact" values of my raster. It >>>> doesn't really make sense to classify a discrete rendering >>>> >>>> So I would say, we still need a render type "discrete raster" which >>>> offers >>>> the function to "retrieve all unique values" (and automatically apply a >>>> discrete color ramp) >>>> >>>> Attached a (fake) test dataset. >>>> >>>> Thanks and cheers >>>> >>>> Stéphane >>>> >>>> >>>> Le lundi 9 janvier 2017, Enrico Fiore <[email protected]> a écrit : >>>> >>>> > Hi, >>>> > Sorry I can't do test, but if you use exact in color interpolation >>>> > parameter? >>>> > >>>> > Cheers >>>> > >>>> > Enrico >>>> >>>> >>>> Le lundi 9 janvier 2017, Stéphane Henriod <[email protected]> a écrit : >>>> >>>> > Hi >>>> > >>>> > unfortunately this is doing quite something different! >>>> > >>>> > If I have a raster with 10 Landcover classes (1,2,3,4,5,6,7,8,9,10) >>>> and I >>>> > want to display only 1,5 and 10, using *Discrete *(1: red, 5: yellow, >>>> 10: >>>> > blue) the following will happen: >>>> > >>>> > All pixels between 1 and 4 will be red >>>> > All pixels between 5 and 9 will be yellow >>>> > All pixels with 10 will be blue >>>> > >>>> > In this sense, the pixels are indeed not interpolated, but this still >>>> is >>>> > not the behavior I am expecting when styling discrete rasters. >>>> > >>>> > A "style discrete raster" function should offer the following: >>>> > >>>> > - Automatically recover all unique values from the raster >>>> > - Only display the pixels to which the user has explicitly >>>> assigned a >>>> > color >>>> > >>>> > But thanks for your hint, this can be helpful in other cases! >>>> > >>>> > Cheers >>>> > >>>> > Stéphane >>>> > >>>> > >>>> > Le lundi 9 janvier 2017, Enrico Fiore <[email protected] >>>> > <javascript:_e(%7B%7D,'cvml','[email protected]');>> a écrit : >>>> > >>>> >> Hi, >>>> >> I think that the solution is in the QGIS documentation, that you can >>>> read >>>> >> here: http://docs.qgis.org/2.14/en/docs/user_manual/working_with_r >>>> >> aster/raster_properties.html#band-rendering >>>> >> you have to use *Singleband pseudocolor *and set color interpolation >>>> to >>>> >> Discrete. >>>> >> >>>> >> Enrico >>>> >> >>>> >> >>>> >> ----Messaggio originale---- >>>> >> Da: "Stéphane Henriod" <[email protected]> >>>> >> Data: 09/01/2017 6.30 >>>> >> A: "qgis-user"<[email protected]> >>>> >> Ogg: [Qgis-user] Symbolizing a discrete or a boolean raster >>>> >> >>>> >> Dear all >>>> >> >>>> >> As much as I love QGIS and use it in my everyday life, there is one >>>> >> feature that I find particularly annoying: the styling of discrete >>>> rasters. >>>> >> >>>> >> Basically, if I have a raster layer consisting of discrete landcover >>>> >> values (1: water, 2: forest, 3: built-up), it seems that there is no >>>> easy >>>> >> way to style it. QGIS will assume that the data is continuous and >>>> basically >>>> >> interpolate the color between each value, which leads to the >>>> following >>>> >> issues: >>>> >> >>>> >> Let's say I want to display only water and built-up (values 1 and 3), >>>> >> water in blue and built-up in grey. QGIS will still display the >>>> forests, >>>> >> using a color somewhere "between" blue and grey. My only left option >>>> is to >>>> >> process the raster to actually replace all the 2 with NoData, which >>>> is >>>> >> highly unpractical... >>>> >> >>>> >> Same if I have a boolean raster (only 0 and 1 values). QGIS will by >>>> >> default make a color ramp from 0 to 0.9999. >>>> >> >>>> >> Also, the whole rather feels like a work-around for a missing >>>> feature. >>>> >> >>>> >> I dream of a feature similar to this one from ArcGIS: >>>> >> http://resources.arcgis.com/en/help/main/10.1/index. >>>> >> html#/representing_unique_categories_such_as_land_use/009t00 >>>> 000074000000/ >>>> >> where all unique values are styled independently and where I can >>>> easily >>>> >> skip the values I don't want to see on my map. >>>> >> >>>> >> I asked a question here: >>>> >> http://gis.stackexchange.com/questions/194116/qgis-style-a-d >>>> >> iscrete-raster >>>> >> >>>> >> and opened a ticket here: >>>> >> http://hub.qgis.org/issues/14845 >>>> >> >>>> >> But none has gotten lots of attention yet... Am I the only one to be >>>> >> annoyed by this? If no, please raise your hand and let's try to get >>>> some >>>> >> momentum and see how to push this feature forward! >>>> >> >>>> >> Thanks a lot in advance! >>>> >> >>>> >> Cheers >>>> >> >>>> >> Stéphane >>>> >> >>>> >> >>>> > >>>> >>>> -- >>>> Stéphane Henriod >>>> CIM-Expert for GIS and Green Economy Statistics >>>> >>>> Национальный статистический комитет Кыргызской Республики >>>> Кыргыз Республикасынын Улуттук статистика комитети >>>> National Statistical Committee of the Kyrgyz Republic >>>> >>>> 374 Фрунзе ул. / Frunze str. >>>> 720033 Бишкек / Bishkek >>>> >>>> T +996 778 46 99 02 (KG) >>>> T +49 176 280 11 050 <+49%20176%2028011050> (DE) >>>> E [email protected] >>>> W http://www.stat.kg >>>> W3W: nightfall.into.bucket >>>> <https://map.what3words.com/nightfall.into.bucket> // >>>> запас.союз.дружный >>>> <https://map.what3words.com/запас.союз.дружный> >>>> -------------- next part -------------- >>>> An HTML attachment was scrubbed... >>>> URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/2017 >>>> 0109/985fd14c/attachment-0001.html> >>>> -------------- next part -------------- >>>> A non-text attachment was scrubbed... >>>> Name: landcover.zip >>>> Type: application/zip >>>> Size: 2151 bytes >>>> Desc: not available >>>> URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/2017 >>>> 0109/985fd14c/attachment-0001.zip> >>>> >>>> ------------------------------ >>>> >>>> Subject: Digest Footer >>>> >>>> _______________________________________________ >>>> Qgis-user mailing list >>>> [email protected] >>>> List info: http://lists.osgeo.org/mailman/listinfo/qgis-user >>>> Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user >>>> >>>> ------------------------------ >>>> >>>> End of Qgis-user Digest, Vol 131, Issue 13 >>>> ****************************************** >>>> >>> >>> >> >> -- >> Stéphane Henriod >> CIM-Expert for GIS and Green Economy Statistics >> >> Национальный статистический комитет Кыргызской Республики >> Кыргыз Республикасынын Улуттук статистика комитети >> National Statistical Committee of the Kyrgyz Republic >> >> 374 Фрунзе ул. / Frunze str. >> 720033 Бишкек / Bishkek >> >> T +996 778 46 99 02 (KG) >> T +49 176 280 11 050 <+49%20176%2028011050> (DE) >> E [email protected] <javascript:_e(%7B%7D,'cvml','[email protected]');> >> W http://www.stat.kg >> W3W: nightfall.into.bucket >> <https://map.what3words.com/nightfall.into.bucket> // >> запас.союз.дружный <https://map.what3words.com/запас.союз.дружный> >> >> >> _______________________________________________ >> Qgis-user mailing list >> [email protected] >> <javascript:_e(%7B%7D,'cvml','[email protected]');> >> List info: http://lists.osgeo.org/mailman/listinfo/qgis-user >> Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user >> > > -- Stéphane Henriod CIM-Expert for GIS and Green Economy Statistics Национальный статистический комитет Кыргызской Республики Кыргыз Республикасынын Улуттук статистика комитети National Statistical Committee of the Kyrgyz Republic 374 Фрунзе ул. / Frunze str. 720033 Бишкек / Bishkek T +996 778 46 99 02 (KG) T +49 176 280 11 050 (DE) E [email protected] W http://www.stat.kg W3W: nightfall.into.bucket <https://map.what3words.com/nightfall.into.bucket> // запас.союз.дружный <https://map.what3words.com/запас.союз.дружный>
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