Nikos, You can use the VRT format [1] in GDAL to perform this. The ComplexSource elements can have an LUT element. It can be used to specify your lookup table. The values in between are interpolated linearly.
[1]: http://www.gdal.org/gdal_vrttut.html On Fri, Jun 10, 2011 at 10:19 PM, Nikolaos Hatzopoulos <nhat...@gmail.com>wrote: > Rapid response for true color has this: > > ;- Rapid Response default enhancement: 0,0, 30,110, 60,160, 120,210, > 190,240, 255,255 > x = byte([0, 30, 60, 120, 190, 255]) > y = byte([0, 110, 160, 210, 240, 255]) > > ;- Rapid Response cloud enhancement: 0,0, 25,90, 55,140, 100,175, 255,255 > if keyword_set(cloud) then begin > x = byte([0, 25, 55, 100, 255]) > y = byte([0, 90, 140, 175, 255]) > endif > > > how it can be programmed in gdal language? > > --Nikos > > > On Thu, Jun 9, 2011 at 8:42 PM, Brian Case <r...@winkey.org> wrote: > >> Nikos >> >> 143, and 721 >> >> Brian >> >> On Thu, 2011-06-09 at 16:49 -0700, Nikolaos Hatzopoulos wrote: >> > for modis truecolor images? >> > >> > --Nikos >> > >> > On Thu, Jun 9, 2011 at 4:44 PM, Brian Case <r...@winkey.org> wrote: >> > Jonathan >> > >> > I don't know about worldview, but with modis I wound up using >> > multiple >> > ranges >> > >> > 0:0,750:110,1500:160,3000:210,4750:240,6375:255 >> > >> > see <lut> in the vrt tutorial >> > >> > Brian >> > >> > >> > >> > >> > >> > >> > >> > On Thu, 2011-06-09 at 12:39 -0700, Jonathan Greenberg wrote: >> > > Brian: >> > > >> > > >> > > Thanks! Great solution, definitely saved me some time. The >> > main >> > > issue (in terms of doing this entirely within GDAL) is >> > getting the >> > > right scaling to make the image look good. I was able to >> > figure out >> > > the correct scale range within ENVI, and then apply the >> > scales as you >> > > suggested below. Nikos' suggestion to use rgb2pct makes me >> > wonder if >> > > there is some way to figure out the optimal scale (which, >> > AFAIK, is >> > > part of how rgb2pct is functioning) to apply to this image. >> > > >> > > >> > > Incidentally, what I'm trying to do is load Worldview-2 data >> > onto an >> > > iPad 2 for use with the GISRoam mobile mapping app. >> > Worldview-2 is >> > > 16-bit per band, 8 band data, with a very high dynamic range >> > (we have >> > > snow in our image, so we have lots of VERY bright pixels >> > which throw >> > > off the adjustment if using -scale without any parameters). >> > 99% >> > > (100%?) of mobile mapping applications need 3-band data, >> > usually with >> > > only 8 bits per band. >> > > >> > > >> > > Pushing forward, but if someone knows how to figure out an >> > optimal set >> > > of scale values to use within GDAL, please post the >> > solution. >> > > >> > > >> > > --j >> > > >> > > On Wed, Jun 8, 2011 at 9:45 PM, Brian Case <r...@winkey.org> >> > wrote: >> > > Jonathan >> > > >> > > you can do scaling on individual bands. >> > > >> > > gdal_translate -b 1 -scale 0 5000 -ot Byte -of VRT >> > infile >> > > outfile1.vrt >> > > gdal_translate -b 2 -scale 0 4000 -ot Byte -of VRT >> > infile >> > > outfile2.vrt >> > > gdal_translate -b 3 -scale 0 3000 -ot Byte -of VRT >> > infile >> > > outfile3.vrt >> > > >> > > gdalbuildvrt -separate output.vrt outfile1.vrt >> > outfile2.vrt >> > > outfile3.vrt >> > > >> > > gdal_translate -of gtiff output.vrt output.tif >> > > >> > > >> > > >> > > for more complicated scaling you may need to hand >> > write a vrt >> > > >> > > http://www.gdal.org/gdal_vrttut.html >> > > >> > > Brian >> > > >> > > >> > > On Wed, 2011-06-08 at 19:31 -0700, Jonathan >> > Greenberg wrote: >> > > > Nikos and GDALers: >> > > > >> > > > >> > > > This is CLOSE to what I'm looking to do, but I'm >> > having a >> > > hard time >> > > > getting it working properly. Here's my input >> > dataset >> > > gdalinfo dump: >> > > > >> > > > >> > > > *** >> > > > >> > > > >> > > > Driver: ENVI/ENVI .hdr Labelled >> > > > Files: >> > > >> > 10SEP10191223-M2AS-052377832030_01_P003_ps_gs_bl_tc.envi >> > > > >> > > >> > 10SEP10191223-M2AS-052377832030_01_P003_ps_gs_bl_tc.hdr >> > > > Size is 42255, 51712 >> > > > Coordinate System is: >> > > > GEOGCS["WGS 84", >> > > > DATUM["WGS_1984", >> > > > SPHEROID["WGS 84",6378137,298.257223563, >> > > > AUTHORITY["EPSG","7030"]], >> > > > TOWGS84[0,0,0,0,0,0,0], >> > > > AUTHORITY["EPSG","6326"]], >> > > > PRIMEM["Greenwich",0, >> > > > AUTHORITY["EPSG","8901"]], >> > > > UNIT["degree",0.0174532925199433, >> > > > AUTHORITY["EPSG","9108"]], >> > > > AUTHORITY["EPSG","4326"]] >> > > > Origin = (-120.066479999999999,39.271554000000002) >> > > > Pixel Size = >> > (0.000004500000005,-0.000004500000005) >> > > > Image Structure Metadata: >> > > > INTERLEAVE=BAND >> > > > Corner Coordinates: >> > > > Upper Left (-120.0664800, 39.2715540) (120d >> > 3'59.33"W, >> > > > 39d16'17.59"N) >> > > > Lower Left (-120.0664800, 39.0388500) (120d >> > 3'59.33"W, 39d >> > > > 2'19.86"N) >> > > > Upper Right (-119.8763325, 39.2715540) >> > (119d52'34.80"W, >> > > > 39d16'17.59"N) >> > > > Lower Right (-119.8763325, 39.0388500) >> > (119d52'34.80"W, 39d >> > > > 2'19.86"N) >> > > > Center (-119.9714062, 39.1552020) >> > (119d58'17.06"W, 39d >> > > > 9'18.73"N) >> > > > Band 1 Block=42255x1 Type=UInt16, >> > ColorInterp=Undefined >> > > > Band 2 Block=42255x1 Type=UInt16, >> > ColorInterp=Undefined >> > > > Band 3 Block=42255x1 Type=UInt16, >> > ColorInterp=Undefined >> > > > >> > > > >> > > > *** >> > > > >> > > > >> > > > I need to end up with a Byte TIF image with good >> > color >> > > balance from >> > > > this input. Running rgb2pct.py on this dataset >> > just >> > > outputted a >> > > > "blank" (grey) image. Running gdal_translate -of >> > GTiff -ot >> > > Byte >> > > > -scale [min] [max] worked somewhat, but its near >> > impossible >> > > to get >> > > > this looking right, since the scaling I want to do >> > differs >> > > from band >> > > > to band (e.g. if there any way to use -scale to >> > adjust each >> > > band >> > > > separately)? Alternatively, how would I get >> > rgb2pct.py >> > > working on the >> > > > above image correctly? Thanks! >> > > > >> > > > >> > > > --j >> > > > >> > > > >> > > > >> > > > On Wed, Jun 8, 2011 at 4:10 PM, Nikolaos >> > Hatzopoulos >> > > > <nhat...@gmail.com> wrote: >> > > > why you don't try rgb2pct >> > > http://www.gdal.org/rgb2pct.html? >> > > > >> > > > --Nikos Hatzopoulos >> > > > >> > > > >> > > > On Wed, Jun 8, 2011 at 2:20 PM, Jonathan >> > Greenberg >> > > > <greenb...@ucdavis.edu> wrote: >> > > > >> > > > >> > > > Folks: >> > > > >> > > > >> > > > I am using a piece of software >> > which is >> > > relying on an >> > > > older version of GDAL that doesn't >> > have the >> > > "fix" to >> > > > deal with > 8 bit geotiffs (it is >> > trying to >> > > make a >> > > > jpeg overlay but can't from a 16 >> > bit image. >> > > I think >> > > > this is the issue: >> > > > >> > > http://trac.osgeo.org/gdal/wiki/TIFF12BitJPEG), but >> > > > when I do a straight convert (-ot >> > Byte) the >> > > output >> > > > image looks really washed out. >> > Any hints >> > > for getting >> > > > the best quality output from a 16 >> > bit to to >> > > an 8 bit >> > > > conversion of a Geotiff? >> > > > >> > > > >> > > > --j >> > > > >> > > > -- >> > > > Jonathan A. Greenberg, PhD >> > > > Assistant Project Scientist >> > > > Center for Spatial Technologies >> > and Remote >> > > Sensing >> > > > (CSTARS) >> > > > Department of Land, Air and Water >> > Resources >> > > > University of California, Davis >> > > > One Shields Avenue >> > > > Davis, CA 95616 >> > > > Phone: 415-763-5476 >> > > > AIM: jgrn307, MSN: >> > jgrn...@hotmail.com, >> > > Gchat: jgrn307 >> > > > >> > > > >> > > > >> > > > >> > > > >> > > _______________________________________________ >> > > > gdal-dev mailing list >> > > > gdal-dev@lists.osgeo.org >> > > > >> > > http://lists.osgeo.org/mailman/listinfo/gdal-dev >> > > > >> > > > >> > > > >> > > > >> > > > -- >> > > > Jonathan A. Greenberg, PhD >> > > > Assistant Project Scientist >> > > > Center for Spatial Technologies and Remote Sensing >> > (CSTARS) >> > > > Department of Land, Air and Water Resources >> > > > University of California, Davis >> > > > One Shields Avenue >> > > > Davis, CA 95616 >> > > > Phone: 415-763-5476 >> > > > AIM: jgrn307, MSN: jgrn...@hotmail.com, Gchat: >> > jgrn307 >> > > > >> > > > >> > > > _______________________________________________ >> > > > gdal-dev mailing list >> > > > gdal-dev@lists.osgeo.org >> > > > http://lists.osgeo.org/mailman/listinfo/gdal-dev >> > > >> > > >> > > >> > > >> > > >> > > >> > > -- >> > > Jonathan A. Greenberg, PhD >> > > Assistant Project Scientist >> > > Center for Spatial Technologies and Remote Sensing (CSTARS) >> > > Department of Land, Air and Water Resources >> > > University of California, Davis >> > > One Shields Avenue >> > > Davis, CA 95616 >> > > Phone: 415-763-5476 >> > > AIM: jgrn307, MSN: jgrn...@hotmail.com, Gchat: jgrn307 >> > > >> > > >> > > _______________________________________________ >> > > gdal-dev mailing list >> > > gdal-dev@lists.osgeo.org >> > > http://lists.osgeo.org/mailman/listinfo/gdal-dev >> > >> > >> > _______________________________________________ >> > gdal-dev mailing list >> > gdal-dev@lists.osgeo.org >> > http://lists.osgeo.org/mailman/listinfo/gdal-dev >> > >> > >> >> >> > > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/gdal-dev > -- Best regards, Chaitanya kumar CH. /tʃaɪθənjə/ /kʊmɑr/ +91-9494447584 17.2416N 80.1426E
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