{"id":382,"date":"2012-08-01T07:55:44","date_gmt":"2012-08-01T04:55:44","guid":{"rendered":"http:\/\/nordicgeocenter.wordpress.com\/?p=382"},"modified":"2012-08-01T07:55:44","modified_gmt":"2012-08-01T04:55:44","slug":"laz-pakkaus-latauksen-aikana","status":"publish","type":"post","link":"https:\/\/geocenter.fi\/blogi\/laz-pakkaus-latauksen-aikana\/","title":{"rendered":"LAZ-pakkaus latauksen aikana"},"content":{"rendered":"

Martin Isenburgilta saapui p\u00e4iv\u00e4n vinkki LAZ-kompressointia tekeville eli siis LAS-tiedostojen zippaukseen.<\/p>\n

Jos LAS-tiedostot ovat ladattavissa FTP:lt\u00e4 kuten esimerkiksi Washingtonin yliopiston tapauksessa<\/p>\n

ftp:\/\/lidar.wustl.edu\/from_WRC\/Franklin\/LAS_Files\/<\/a><\/div>\n
niin 3 GB tiedostojen latauksen ja latauksen j\u00e4lkeisen zippauksen sijaan tiedostot voi pakata suoraan latauksen aikana ja n\u00e4in s\u00e4\u00e4st\u00e4\u00e4 koneen kiintolevy\u00e4. T\u00e4m\u00e4n operaation tekemiseksi tarvitaan ”laszip.exe<\/a>” sek\u00e4 ”curl.exe” (l\u00f6ytyy Google-haulla), jotka sitten ajetaan rinnakkain alla olevan esimerkin tapaan:<\/div>\n
curl -s ftp:\/\/lidar.wustl.edu\/from_WRC\/Franklin\/LAS_Files\/38090e7_NW.las<\/a> | laszip -stdin -o 38090e7_NW.laz<\/div>\n
T\u00e4ll\u00e4 komennolla tiedosto ”38090e7_NW.las” kirjoitetaan latautuessaan koneelle suoraan muotoon ”38090e7_NW.laz”. Operaation tehovaatimuksia voi samalla tarkkailla tiedostonhallinnasta ja samalla voidaan arvioida pakkausuhde tarkastelemalla ”I\/O Read Bytes” ja ”I\/O Write Bytes”sarakkeita.<\/div>\n
\"\"<\/a><\/div>\n
Ohjelma toimii my\u00f6s k\u00e4\u00e4nteisesti, eli jos l\u00e4ht\u00f6tiedosto on .LAZ ja se halutaan ladattaessa muuttuu .LAS-muotoon.<\/div>\n
<\/div>\n
Samalla tavalla curl.exen ja lasinfo.exen avulla voidaan tarkastella LAS-tiedoston tietoja lataamatta tiedostoa ollenkaan palvelimelta.curl -s ftp:\/\/lidar.wustl.edu\/from_WRC\/Franklin\/LAS_Files\/38090e7_NW.las<\/a> | lasinfo -nc -stdin<\/p>\n<\/div>\n
<\/div>\n
Tulokseksi saadaan:<\/div>\n
reporting all LAS header entries:
\nfile signature: ’LASF’
\nfile source ID: 0
\nglobal_encoding: 0
\nproject ID GUID data 1-4: 3507991416 36513 17806 ’\u20a7{\u00fc\u00f7g\u2514\u2558p’
\nversion major.minor: 1.2
\nsystem identifier: ’NIIRS10’
\ngenerating software: ’LIDAR1 tiled’
\nfile creation day\/year: 243\/2011
\nheader size: 227
\noffset to point data: 4746
\nnumber var. length records: 5
\npoint data format: 1
\npoint data record length: 28
\nnumber of point records: 11910401
\nnumber of points by return: 9643615 1613716 550472 102598 0
\nscale factor x y z: 0.01 0.01 0.01
\noffset x y z: 0 0 0
\nmin x y z: 686488.13 4270318.00 120.44
\nmax x y z: 690642.00 4272813.32 659.85
\nvariable length header record 1 of 5:
\nreserved 43707
\nuser ID ’LASF_Projection’
\nrecord ID 34735
\nlength after header 192
\ndescription ’GeoTiff Projection Keys’
\nGeoKeyDirectoryTag version 1.1.0 number of keys 23
\nkey 1024 tiff_tag_location 0 count 1 value_offset 1 – GTModelTypeGeoKey: ModelTypeProjected
\nkey 2048 tiff_tag_location 0 count 1 value_offset 4269 – GeographicTypeGeoKey: GCS_NAD83
\nkey 2049 tiff_tag_location 34737 count 24 value_offset 48 – GeogCitationGeoKey: GCS_North_American_1983
\nkey 2050 tiff_tag_location 0 count 1 value_offset 6269 – GeogGeodeticDatumGeoKey: Datum_North_American_Datum_1983
\nkey 2051 tiff_tag_location 0 count 1 value_offset 8901 – GeogPrimeMeridianGeoKey: PM_Greenwich
\nkey 2054 tiff_tag_location 0 count 1 value_offset 9102 – GeogAngularUnitsGeoKey: Angular_Degree
\nkey 2055 tiff_tag_location 34736 count 1 value_offset 9 – GeogAngularUnitSizeGeoKey: 0.01745329252
\nkey 2056 tiff_tag_location 0 count 1 value_offset 7019 – GeogEllipsoidGeoKey: Ellipse_GRS_1980
\nkey 2057 tiff_tag_location 34736 count 1 value_offset 6 – GeogSemiMajorAxisGeoKey: 6378137
\nkey 2059 tiff_tag_location 34736 count 1 value_offset 7 – GeogInvFlatteningGeoKey: 298.2572221
\nkey 2061 tiff_tag_location 34736 count 1 value_offset 8 – GeogPrimeMeridianLongGeoKey: 0
\nkey 3072 tiff_tag_location 0 count 1 value_offset 26915 – ProjectedCSTypeGeoKey: PCS_NAD83_UTM_zone_15N
\nkey 3073 tiff_tag_location 34737 count 22 value_offset 0 – PCSCitationGeoKey: NAD_1983_UTM_Zone_15N
\nkey 3075 tiff_tag_location 0 count 1 value_offset 1 – ProjCoordTransGeoKey: CT_TransverseMercator
\nkey 3076 tiff_tag_location 0 count 1 value_offset 9001 – ProjLinearUnitsGeoKey: Linear_Meter
\nkey 3077 tiff_tag_location 34736 count 1 value_offset 5 – ProjLinearUnitSizeGeoKey: 1
\nkey 3081 tiff_tag_location 34736 count 1 value_offset 4 – ProjNatOriginLatGeoKey: 0
\nkey 3082 tiff_tag_location 34736 count 1 value_offset 0 – ProjFalseEastingGeoKey: 500000
\nkey 3083 tiff_tag_location 34736 count 1 value_offset 1 – ProjFalseNorthingGeoKey: 0
\nkey 3088 tiff_tag_location 34736 count 1 value_offset 2 – ProjCenterLongGeoKey: -93
\nkey 3092 tiff_tag_location 34736 count 1 value_offset 3 – ProjScaleAtNatOriginGeoKey: 0.9996
\nkey 4097 tiff_tag_location 34737 count 26 value_offset 22 – VerticalCitationGeoKey: NAVD88 – Geoid03 (Meters)
\nkey 4099 tiff_tag_location 0 count 1 value_offset 9001 – VerticalUnitsGeoKey: Linear_Meter
\nvariable length header record 2 of 5:
\nreserved 43707
\nuser ID ’LASF_Projection’
\nrecord ID 34736
\nlength after header 80
\ndescription ’GeoTiff double parameters’
\nGeoDoubleParamsTag (number of doubles 10)
\n500000 0 -93 0.9996 0 1 6.37814e+006 298.257 0 0.0174533
\nvariable length header record 3 of 5:
\nreserved 43707
\nuser ID ’LASF_Projection’
\nrecord ID 34737
\nlength after header 73
\ndescription ’GeoTiff ASCII parameters’
\nGeoAsciiParamsTag (number of characters 73)
\nNAD_1983_UTM_Zone_15N|NAVD88 – Geoid03 (Meters)|GCS_North_American_1983|
\nvariable length header record 4 of 5:
\nreserved 43707
\nuser ID ’NIIRS10’
\nrecord ID 4
\nlength after header 10
\ndescription ’NIIRS10 Timestamp’
\nvariable length header record 5 of 5:
\nreserved 43707
\nuser ID ’NIIRS10’
\nrecord ID 1
\nlength after header 26
\ndescription ’NIIRS10 Tile Index’
\nthe header is followed by 3868 user-defined bytes<\/div>\n","protected":false},"excerpt":{"rendered":"

Martin Isenburgilta saapui p\u00e4iv\u00e4n vinkki LAZ-kompressointia tekeville eli siis LAS-tiedostojen zippaukseen. Jos LAS-tiedostot ovat ladattavissa FTP:lt\u00e4 kuten esimerkiksi Washingtonin yliopiston tapauksessa ftp:\/\/lidar.wustl.edu\/from_WRC\/Franklin\/LAS_Files\/ niin 3 GB tiedostojen latauksen ja latauksen j\u00e4lkeisen zippauksen sijaan tiedostot voi pakata suoraan latauksen aikana ja n\u00e4in s\u00e4\u00e4st\u00e4\u00e4 koneen kiintolevy\u00e4. T\u00e4m\u00e4n operaation tekemiseksi tarvitaan ”laszip.exe” sek\u00e4 ”curl.exe” (l\u00f6ytyy Google-haulla), jotka sitten ajetaan […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-382","post","type-post","status-publish","format-standard","hentry","category-laserkeilaus"],"_links":{"self":[{"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/posts\/382","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/comments?post=382"}],"version-history":[{"count":0,"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/posts\/382\/revisions"}],"wp:attachment":[{"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/media?parent=382"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/categories?post=382"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/geocenter.fi\/blogi\/wp-json\/wp\/v2\/tags?post=382"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}