Re: [Qgis-user] map projection in Myanmar
Dear Wirote, Thank you very much. It will surely help. -Leo On Mon, Jan 28, 2013 at 6:38 PM, Wirote Laongmanee wirot...@gmail.comwrote: Dear Leo, In Thailand, we are using UTM Zone 47N for majority part and 48N at east part of Thailand. And also we are using WGS84-Latlon together, we also remain Indian Datum 1975 data but need to consider when work together. In Myanmar I am not sure there are specific projection or not but when we handle their data we selected WGS84/UTM Zone 46 N, it work well. May help you. Wirote On Mon, Jan 28, 2013 at 5:27 PM, Leo Kris Palao lk.pa...@gmail.comwrote: Good Day QGIS Users, Would like to ask what map projection is suitable for Myanmar? Is it okay to use UTM coordinate system or can you recommend other coordinate system? Thank you. -Leo ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user -- Wirote Laongmanee http://wmap.wordpress.com http://parn-site.blogspot.com -- *** *LEO KRIS M. PALAO* Researcher World Agroforestry Centre (International Centre for Research in Agroforestry) Mobile #: +63(916)7698-367 E-mail: l.pa...@irri.org or lk.pa...@gmail.com *Transforming Lives and Landscapes * ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] JPeg compression of tiff-file
Hi. Maybe little of topic but... I have found a ortofoto as a Geotiff-file that are compressed with jpeg. Why kompress tiff with jpeg and not make the hole file as jpg? Cheers ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Hotlink field definition
Hi Philippe, you just have to define native actions on layers as described in manual or here. This is located in layer properties/ tab actions. Since 1.8, you can add examples to help you define different actions. If you alreadyu have a url or a field path in a field, just use open action, and insert the name of your field with the tool that inserts an expression. It should be something like [%myfield%] Régis -- View this message in context: http://osgeo-org.1560.n6.nabble.com/Hotlink-field-definition-tp5030749p5030861.html Sent from the Quantum GIS - User mailing list archive at Nabble.com. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Installing plugins offline
Dear Claire, did you copy plugin into your personal plugin directory? From the \ in the path I suppose you use Windows, then you should copy the plugin into a subdirectory of \Documents and Settings\user name\.qgis\python\plugin Regards, Zoltan On Wed, 30 Jan 2013, Claire McIntyre wrote: Hello, I need to install plugins offline. I have read in posts to download from web unzip to qgis\python\plugins I have done this and the plugins are visible when I go to Manage Plugins. When I check the plugin to enable it I get an error. I suspect the file are in the correct place but not registered/installed correctly. Other posts are saying QGIS must be connected to the internet, there is no way round.. I am using QGIS 1.8 on windows. Anyone know how I can get this working? Thanks, Claire Sent from mobile device ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] JPeg compression of tiff-file
Hi, Geotiff files can have tiles and overviews and georeference information whereas jpeg files cannot to my knowledge. Georeference information for jpeg files are stored in separate jpw files. Besides, due to tiling and overviews tif files can be very large. You could store all orthoimages of your region in a single file without performance problems. Personally I use JPEG compressed tif files for all of my orthoimages. I don't like ECW or MrSid due to the unclear license issues. If you look into the archives of this list you see that people have troubles with these closed formats. Andreas Johan Nilsson joni8...@gmail.com schrieb: Hi. Maybe little of topic but... I have found a ortofoto as a Geotiff-file that are compressed with jpeg. Why kompress tiff with jpeg and not make the hole file as jpg? Cheers ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user -- Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet.___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Split polygon using area and DEM
Dear Colleagues, I am tasked with defining harvesting strips for a community forest in Zambia and am struggling to find a suitable solution. Our approach uses the coop and shelter belt (harvest alternative strips of forest) method and requires that our area be split into 5 ha blocks. I understand how to make a grid of 5 ha blocks, however, we have a topography issue. Our site is located in some pretty hilly areas so we want to harvest along contours to avoid soil erosion issues. I am looking for a quantitative approach to portioning our site up into 5ha blocks that run along contours. I have access to QGIS and R as well as any other FOSS available. Do any of the Qgis users have a suggestion with regards to a suitable approach? Many thanks, Wesley -- Dr Wesley Roberts jwesrobe...@gmail.com Cell: +27(0)83 5355 646 skype: roberts-w ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] out-db postgis raster issue
Hi, Just wondering if anyone had any thoughts on my issue loading out-db / filesystem stored rasters from PostGIS. I began to wonder if the data had loaded correctly but came across the following psql method to get a basic image out and it is fine: postgis20test=# SELECT oid, lowrite(lo_open(oid, 131072),png) AS num_bytes FROM ( VALUES (lo_create(0), ST_AsPNG((SELECT rast FROM public.raster2pgsqltest_local _outdb WHERE rid=1)) )) AS v(oid,png); oid | num_bytes ---+--- 19094 | 8769 (1 row) postgis20test=# \lo_export 19094 `C:/test.png` However, i note a PostGIS raster option ST_AsGDALRaster and i tried replacing the ST_AsPNG clause with this (which runs as a SELECT query) and it doesn't seem to work. ST_asgdalraster((SELECT rast FROM public.raster2pgsqltest_local_outdb WHERE rid=1),'png',NULL,27700) Any ideas on what i can do to further narrow down my search for the issue would be fantastic? Or even if i'm asking in the wrong place... i have also popped something on the gdal site. Andy -- View this message in context: http://osgeo-org.1560.n6.nabble.com/out-db-postgis-raster-issue-tp5028921p5030866.html Sent from the Quantum GIS - User mailing list archive at Nabble.com. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] JPeg compression of tiff-file
Hi Johan, There may be two reasons why the opening of the tiff files take so long: 1. They do not have internal pyramids. 2. Your QGIS version is calculating histograms You can see if your raster files have pyramids by checking the pyramids tab in the raster layer properties. If they do not have the pyramids you will see red cross-marks. You can build or rebuild the pyramids directly from this tab. Depending on the file-size the process of pyramid building takes a long time. As to two: some QGIS versions out there (don't ask me which version exactly) always calculated histograms on opening the file. If you have such a version, you should upgrade your QGIS. If neither of the above are the case the file should open in less than a second, regardless of the file size. The recommended compression inside the tiff-file depends on the nature of the data: Pure black and white files or files with a handful of colors should not be jpeg-compressed. A better compression would be deflate or ccittrle or rle. These are all lossless compressions. JPEG is a lossy compression. For photo-data or maps with a lot of colors, also for grayscale photos, JPEG is the better option. You can also set the quality. Be aware though that JPEG can destroy bits of the data (depending on the quality setting) - so keep your original data as well. See http://www.gdal.org/frmt_gtiff.html for more information. Hope this helps. Andreas On Wed, 30 Jan 2013 10:40:45 +0100, Johan Nilsson wrote: Thanks. Little as I suspected, but even more and that are maybe a way for me to find a solution... I have a lot of pure tiff files as black and white ortophoto from different years, but when I open the project in Qgis is take a long time to 'read in' them. Is there a solution to save ortophoto (tiff files) and just load them that are of interest? I have just add them as raster in a project in Qgis. There tiff-files have namne korrensponding to a grid number. 2013/1/30 Andreas Neumann Hi, Geotiff files can have tiles and overviews and georeference information whereas jpeg files cannot to my knowledge. Georeference information for jpeg files are stored in separate jpw files. Besides, due to tiling and overviews tif files can be very large. You could store all orthoimages of your region in a single file without performance problems. Personally I use JPEG compressed tif files for all of my orthoimages. I don't like ECW or MrSid due to the unclear license issues. If you look into the archives of this list you see that people have troubles with these closed formats. Andreas Johan Nilsson schrieb: Hi. Maybe little of topic but... I have found a ortofoto as a Geotiff-file that are compressed with jpeg. Why kompress tiff with jpeg and not make the hole file as jpg? Cheers - Qgis-user mailing list Qgis-user@lists.osgeo.org [1] http://lists.osgeo.org/mailman/listinfo/qgis-user [2] -- Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet. Links: -- [1] mailto:Qgis-user@lists.osgeo.org [2] http://lists.osgeo.org/mailman/listinfo/qgis-user [3] mailto:joni8...@gmail.com [4] mailto:a.neum...@carto.net -- -- Andreas Neumann Böschacherstrasse 10A 8624 Grüt (Gossau ZH) Switzerland ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Fwd: Layer encoding
Am 30.01.2013 08:45, schrieb Matej Mailing: thanks for answering. Just a question: does the master exist for windows platform (already compiled)? Yes, part of the OSGEO4W setup. It can be installed in parallel to the stable version. You can find a lot of workarounds here: http://gis.stackexchange.com/questions/44009/how-to-read-greek-fonts-iso-8859-7-in-shapefile-attributes-within-qgis-1-8-0 It's also kind of operating-system-specific. Greetings, André Joost ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] JPeg compression of tiff-file
Tanks. I havee the ortophoto on read-only partition :( Should be nise to move them without to make a new workspace or get a easy way lo load them in another projekt. The normal compressuon with tiff are undestuctive LWZ i think. It takes about a second / photo even fore those I don't have visable. I have around 200. Dennsdagen den 30:e januari 2013 skrev Andreas Neumanna.neum...@carto.net: Hi Johan, There may be two reasons why the opening of the tiff files take so long: 1. They do not have internal pyramids. 2. Your QGIS version is calculating histograms You can see if your raster files have pyramids by checking the pyramids tab in the raster layer properties. If they do not have the pyramids you will see red cross-marks. You can build or rebuild the pyramids directly from this tab. Depending on the file-size the process of pyramid building takes a long time. As to two: some QGIS versions out there (don't ask me which version exactly) always calculated histograms on opening the file. If you have such a version, you should upgrade your QGIS. If neither of the above are the case the file should open in less than a second, regardless of the file size. The recommended compression inside the tiff-file depends on the nature of the data: Pure black and white files or files with a handful of colors should not be jpeg-compressed. A better compression would be deflate or ccittrle or rle. These are all lossless compressions. JPEG is a lossy compression. For photo-data or maps with a lot of colors, also for grayscale photos, JPEG is the better option. You can also set the quality. Be aware though that JPEG can destroy bits of the data (depending on the quality setting) - so keep your original data as well. See http://www.gdal.org/frmt_gtiff.html for more information. Hope this helps. Andreas On Wed, 30 Jan 2013 10:40:45 +0100, Johan Nilsson wrote: Thanks. Little as I suspected, but even more and that are maybe a way for me to find a solution... I have a lot of pure tiff files as black and white ortophoto from different years, but when I open the project in Qgis is take a long time to 'read in' them. Is there a solution to save ortophoto (tiff files) and just load them that are of interest? I have just add them as raster in a project in Qgis. There tiff-files have namne korrensponding to a grid number. 2013/1/30 Andreas Neumann Hi, Geotiff files can have tiles and overviews and georeference information whereas jpeg files cannot to my knowledge. Georeference information for jpeg files are stored in separate jpw files. Besides, due to tiling and overviews tif files can be very large. You could store all orthoimages of your region in a single file without performance problems. Personally I use JPEG compressed tif files for all of my orthoimages. I don't like ECW or MrSid due to the unclear license issues. If you look into the archives of this list you see that people have troubles with these closed formats. Andreas Johan Nilsson schrieb: Hi. Maybe little of topic but... I have found a ortofoto as a Geotiff-file that are compressed with jpeg. Why kompress tiff with jpeg and not make the hole file as jpg? Cheers - Qgis-user mailing list Qgis-user@lists.osgeo.org [1] http://lists.osgeo.org/mailman/listinfo/qgis-user [2] -- Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet. Links: -- [1] mailto:Qgis-user@lists.osgeo.org [2] http://lists.osgeo.org/mailman/listinfo/qgis-user [3] mailto:joni8...@gmail.com [4] mailto:a.neum...@carto.net -- -- Andreas Neumann Böschacherstrasse 10A 8624 Grüt (Gossau ZH) Switzerland ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
