Hi Jukka, The value I use for test was retrieve using qgis defaults so I don't know if your formula was the same.
So I do a quick test these are the values for my test raster: Band 1 Minimum=0.038, Maximum=1.584, Mean=0.135, StdDev=0.026 Band 2 Minimum=0.004, Maximum=1.567, Mean=0.115, StdDev=0.027 Band 3 Minimum=0.003, Maximum=1.636, Mean=0.096, StdDev=0.031 Band 4 Minimum=-0.016, Maximum=1.796, Mean=0.082, StdDev=0.042 Band 5 Minimum=-0.311, Maximum=4.486, Mean=0.256, StdDev=0.138 Band 6 Minimum=-0.197, Maximum=3.277, Mean=0.161, StdDev=0.098 Band 7 Minimum=-0.118, Maximum=2.295, Mean=0.088, StdDev=0.063 Band 8 Minimum=0.039, Maximum=1.366, Mean=0.090, StdDev=0.035 Band 9 Minimum=-0.039, Maximum=0.413, Mean=0.003, StdDev=0.010 Band 10 Minimum=240.580, Maximum=524.602, Mean=299.351, StdDev=6.342 Band 11 Minimum=249.037, Maximum=514.462, Mean=297.375, StdDev=5.855 Using you formula: (I hope to understand it correctly) PROCESSING "BANDS=4,3,2" (the red,green,blue channels) the values should be: Band 4: 0.082 - (-0.016 * 0.042) = 0.082672 0.082 + (1.796 * 0.042) = 0.157432 Band 3: 0.096 - (0.003 * 0.031) = 0.095907 0.096 + (1.636 * 0.031) = 0.146716 Band 2: 0.115 - (0.004 * 0.027) = 0.114892 0.115 + (1.567 * 0.027) = 0.157309 so the setting should be: PROCESSING "SCALE_1= 0.082672 , 0.157432" PROCESSING "SCALE_2= 0.095907 , 0.146716" PROCESSING "SCALE_3= 0.114892 , 0.157309" With this values the image is not correct . I add a link to a sample images of what the mapserver will produce with these values. https://www.dropbox.com/s/izleegjbp18j81f/sample-mapserver-with-values.gif?dl=0 A. 2015-08-04 22:52 GMT+02:00 Rahkonen Jukka (MML) <[email protected]>: > Hi, > > Do we talk about the same thing? If gdalinfo -stats shows > Minimum=2.000, Maximum=255.000, Mean=96.297, StdDev=37.015 > you should put min at 96.297-(2*37.015) > You can test the effect with QGIS as described here > http://gis.stackexchange.com/questions/87914/how-to-perform-a-standard-deviation-stretch-on-a-raster-in-qgis > However, I have not really used 64-bit images and don't know what kind of > histograms they usually have. > > In Mapserver 2.0 the PROCESSING stuff should be possible to set via variable > substitution and your users could make the adjustment on-the-fly. Perhaps > they could accept that? > > -Jukka- > > Andrea Peri wrote: > >> Hi Jukka, I could open a feature request for this, but before I need to >> understand if the results with this strategy are affordable for us. > >> Infact I do some test with a domain min/max lesser than 2x and it results >> unaccepatable for our users. The raster are too poor contrasted as reported >> me from our users. >> So I'm not sure that an AUTO with a STD stretch and a multiplicator 2x could >> be instead an acceptable solution. > > I should do more tests... > > Thx. > > > > 2015-08-04 20:29 GMT+02:00 Rahkonen Jukka (MML) > <[email protected]>: >> Hi Andrea, >> >> For viewing purposes it is rather common to do LUT stretch by standard >> deviation which is not so sensible as min-max stretch. Consider making a >> feature request for a new enhanced PROCESSING AUTO directive which would do >> the STD stretch, possibly with an optional multiplication. 2 x STD might be >> a good default value. >> >> -Jukka Rahkonen- >> >> Andrea Peri wrote: >> >>> HI Jukka, >>> unfortunatelly, I cannot use the LUT because the raster I use is update >>> weekly and every week it could change the min/max values for every bands >>> (it has 11 bands). >> >>> Hovewer if it work using the min/max from get map , probably it could be ok >>> form me. >>> The question s that even when the getmap request the entire bbox the image >>> reported seem to be empty without no error log. >> >> >> >> 2015-08-04 19:50 GMT+02:00 Rahkonen Jukka (MML) >> <[email protected]>: >>> Hi, >>> >>> I suppose that Even means that with AUTO setting Mapserver is analyzing the >>> min/max pixel values from inside the BBOX of each GetMap and then scales >>> pixel values to 0-256 for the output. One totally black or white pixel >>> within the BBOX can make the result from 64bit source very bad. >>> >>> I would try to use LUT instead of SCALE >>> http://www.mapserver.org/input/raster.html#special-processing-directives. >>> >>> -Jukka Rahkonen- >>> >>> >>> >>> >>> -----Alkuperäinen viesti-----l >>> Lähettäjä: [email protected] >>> [mailto:[email protected]] Puolesta Andrea Peri >>> Lähetetty: 4. elokuuta 2015 20:07 >>> Vastaanottaja: Even Rouault >>> Kopio: [email protected] >>> Aihe: Re: [mapserver-users] processing scale=auto with float >>> multibands rasters >>> >>> Hi Even, >>> >>> thx for response. >>> >>> Please can you help me to better understand the question ? >>> >>> My raster is effectively a 18000 x 24000 px image with tiles. >>> >>> it have a tile size of 1024 x 1024 produced from gdalwarp: >>> >>> gdalwarp -s_srs EPSG:32632 -t_srs EPSG:32632 -overwrite --config >>> GDAL_CACHEMAX 1000 -wm 1000 -co TILED=YES -co COMPRESS=NONE -co >>> BLOCKXSIZE=1024 -co BLOCKYSIZE=1024 -co BIGTIFF=YES -co SPARSE_OK=TRUE >>> ....... >>> >>> and also have overviews from >>> >>> gdaladdo --config GDAL_CACHEMAX 1500 -ro -r average ..... 2 4 8 16 32 >>> 64 128 256 512 1024 >>> >>> If I understand correctly your info. >>> The mapserver could search the min/max using only the first tile ? >>> >>> This mean that it more probably found always only 0 values or near 0 values >>> beacuse these could be the values in the first tile. >>> >>> And so it return a white image because the min/max is always min=0/ >>> max=0 (or something quite like this) >>> I understand correct ? >>> >>> thx, >>> >>> A. >>> >>> >>> 2015-08-04 16:01 GMT+02:00 Even Rouault <[email protected]>: >>>> On Monday 03 August 2015 11:02:43 Andrea Peri wrote: >>>>> Hi, >>>>> I have a geotiff multibands with float64 values to serve with a wms >>>>> mapserver service. >>>>> >>>>> With this kind of rasters, >>>>> is affordable the directive >>>>> >>>>> PROCESSING "BANDS=4,3,2" >>>>> PROCESSING "SCALE=AUTO" >>>>> >>>>> (the 4,3,2 are the red,green,blue channels) >>>>> >>>>> Infact it seem do nothing. >>>>> >>>>> Instead all work well if I set: >>>>> >>>>> PROCESSING "BANDS=4,3,2" >>>>> PROCESSING "SCALE_1=0.01,0.2" >>>>> PROCESSING "SCALE_2=0.01,0.2" >>>>> PROCESSING "SCALE_3=0.01,0.2" >>>>> >>>>> where ii use the min=0.01 and max=0.2 But I like to have the exact >>>>> values of min/max for every raster. >>>> >>>> Andrea, >>>> >>>> SCALE=AUTO should work but looking at the actual implementation I >>>> can see it computes the min/max on the pixel values intersecting the >>>> requested area, and not on the whole raster as I'd have expected. So >>>> in a tiling context, it will likely not produce the expected result. >>>> >>>> Even >>>> >>>> -- >>>> Spatialys - Geospatial professional services >>>> http://www.spatialys.com >>> >>> >>> >>> -- >>> ----------------- >>> Andrea Peri >>> . . . . . . . . . >>> qwerty àèìòù >>> ----------------- >>> _______________________________________________ >>> mapserver-users mailing list >>> [email protected] >>> http://lists.osgeo.org/mailman/listinfo/mapserver-users >> >> >> >> -- >> ----------------- >> Andrea Peri >> . . . . . . . . . >> qwerty àèìòù >> ----------------- > > > > -- > ----------------- > Andrea Peri > . . . . . . . . . > qwerty àèìòù > ----------------- -- ----------------- Andrea Peri . . . . . . . . . qwerty àèìòù ----------------- _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
