U.S. Geological Survey LEVEL-1 PRODUCT README: GeoTIFF TABLE OF CONTENTS INTRODUCTION FORMAT ORGANIZATION * DATA FILE NAMES * GAP MASKS * README * READING DATA GENERAL INFORMATION and DOCUMENTATION PRODUCT SUPPORT DISCLAIMER INTRODUCTION This product was created by the U.S. Geological Survey (USGS) and contains Landsat data files in Geographic Tagged Image-File Format (GeoTIFF). The Landsat 1, 2, and 3 satellites carried the Multispectral Scanner (MSS) sensor; the Landsat 4 and 5 satellites carry both the MSS and the Thematic Mapper (TM) sensors; and the Landsat 7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. These sensors support the Landsat Project’s mission to provide quality remote sensing data in support of research and applications activities. For information on MSS products (Landsats 1-5): http://eros.usgs.gov/products/satellite/mss.php For information on TM products (Landsats 4-5): http://eros.usgs.gov/products/satellite/tm.php For information on ETM+ products (Landsat 7): http://eros.usgs.gov/products/satellite/landsat7.php For information on the Landsat Project, the Landsat Data Continuity Mission (LDCM), project documentation, and data acquisitions: http://landsat.usgs.gov For detailed information on the Landsat 7 satellite, the ETM+ sensor, and Landsat 7 data products: http://landsathandbook.gsfc.nasa.gov/handbook.html FORMAT Landsat MSS, TM, and ETM+ data are provided in GeoTIFF for Level 1T (terrain corrected) products, or for either Level 1Gt (systematic terrain corrected) or Level 1G (systematic corrected) products, if Level 1T processing is not available. GeoTIFF defines a set of publicly available TIFF tags that describe cartographic and geodetic information associated with TIFF images. GeoTIFF is a format that enables referencing a raster image to a known geodetic model or map projection. The initial tags are followed by image data that, in turn, may be interrupted by more descriptive tags. By using the GeoTIFF format, both metadata and image data can be encoded into the same file. The Landsat 7 ETM+ GeoTIFF file format is described in detail in the "Landsat 7 ETM+ Level 1 Product Data Format Control Book (DFCB), LS-DFCB-04": http://landsat.usgs.gov/documents/LS_DFCB_04.pdf The Landsat 4-5 TM GeoTIFF file format is described in detail in the "Landsat Thematic Mapper (TM) Level 1 (L1) Data Format Control Book (DFCB), LS-DFCB-20": http://landsat.usgs.gov/documents/LS_DFCB_20_TM_Level_1_DFCB.pdf For more information on GeoTIFF visit: http://trac.osgeo.org/geotiff ORGANIZATION Each band of Landsat data in the GeoTIFF format is delivered as a grayscale, uncompressed, 8-bit string of unsigned integers. A metadata (MTL) file is included with data processed through the Level-1 Product Generation System (LPGS). A file containing the ground control points (GCP) used during image processing is also included. A processing history (WO) file is included with data processed through the National Landsat Archive Production System (NLAPS). Landsat 7 ETM+ SLC-off products processed after December 11, 2008, will include an additional directory (gap_mask) that contains a set of flat binary scan gap mask files (one per band). (Please note that the processing date and acquisition date are not necessarily the same.) * DATA FILE NAMES The file naming convention for Landsat LPGS-processed GeoTIFF data is as follows: LLfppprrr_rrrYYYYMMDD_AAA.TIF where: LL = Landsat sensor (LE for ETM+ data; LT for TM data) f = ETM+ data format (1, 2, or G) (character omitted from TM file name) ppp = starting path of the product rrr_rrr = starting and ending rows of the product YYYYMMDD = acquisition date of the image AAA = file type: B10 = band 1 B20 = band 2 B30 = band 3 B40 = band 4 B50 = band 5 B61 = band 6L (low gain) B62 = band 6H (high gain) B70 = band 7 B80 = band 8 MTL = Level-1 metadata GCP = ground control points TIF = GeoTIFF file extension The file naming convention for Landsat NLAPS-processed GeoTIFF data is as follows: LLNppprrrOOYYDDDMM_AA.TIF where: LL = Landsat sensor (LM for MSS data; LT for TM data) N = satellite number ppp = starting path of the product rrr = starting row of the product OO = WRS row offset (set to 00) YY = last two digits of the year of acquisition DDD = Julian date of acquisition MM = instrument mode (10 for MSS; 50 for TM) AA = file type: B1 = band 1 B2 = band 2 B3 = band 3 B4 = band 4 B5 = band 5 B6 = band 6 B7 = band 7 WO = processing history file TIF = GeoTIFF file extension * GAP MASKS All Landsat 7 ETM+ SLC-off imagery processed on or after December 11, 2008, will include gap mask files. (Please note the difference between acquisition date and processing date.) The gap mask files are bit mask files showing the locations of the image gaps (areas that fall between ETM+ scans). One tarred and gzip-compressed gap mask file is provided for each band in GeoTIFF format. The file naming convention for gap mask files is identical to that described above for LPGS-processed GeoTIFF data, with the third character (data format) set as 'G'. If gap mask files are not included with the data, a tutorial for creating them can be found at: http://landsat.usgs.gov/gap_mask_files_are_not_provided_can_I_create_my_own.php * README The README_GTF.TXT (or README.GTF) is an ASCII text file and is this file. * READING DATA Delivered via file transfer protocol (FTP): data files are tarred and g-zip compressed and will need to be unzipped and untarred before the data files can be used. UNIX systems should have the "gunzip" and "tar" commands available for uncompressing and accessing the data. For PC users, free software can be downloaded from an online source. Otherwise, check your PC, as you may already have appropriate software available. No software is included on this product for viewing Landsat data. GENERAL INFORMATION and DOCUMENTATION Landsat and the Landsat Data Continuity Mission (LDCM): http://landsat.usgs.gov Landsat 7 (ETM+): http://eros.usgs.gov/products/satellite/landsat7.php Landsat 4-5 (TM): http://eros.usgs.gov/products/satellite/tm.php Landsat 1-5 (MSS): http://eros.usgs.gov/products/satellite/mss.php Landsat data access: * USGS Global Visualization Viewer (GloVis): http://glovis.usgs.gov * USGS EarthExplorer: http://earthexplorer.usgs.gov * Landsat International Ground Station (IGS) network: http://landsat.usgs.gov/about_ground_stations.php FGDC metadata: http://clearinghouse1.fgdc.gov/fgdc/EDCgateway.html Data restrictions and citation: http://eros.usgs.gov/about/customer/citation.html * National Snow and Ice Data Center (NSIDC) Radarsat Antarctic Mapping Project (RAMP) elevation data citation: Liu, H., K. Jezek, B. Li, and Z. Zhao. 2001. Radarsat Antarctic Mapping Project digital elevation model version 2. Boulder, CO: National Snow and Ice Data Center. Digital media. For information on the data, please refer to the data set documentation available at the following web site: http://nsidc.org/data/nsidc-0082.html PRODUCT SUPPORT For further information on this product, contact USGS EROS Customer Services: Customer Services (ATTN: Landsat) U.S. Geological Survey Earth Resources Observation and Science (EROS) Center 47914 252nd Street Sioux Falls, SD 57198-0001 Tel: 800-252-4547 Tel: 605-594-6151 Fax: 605-594-6589 Email: custserv@usgs.gov Web: http://eros.usgs.gov/about/customer/index.html For information on other products from USGS EROS: http://eros.usgs.gov/ For information on other USGS products: http://ask.usgs.gov/ or call 1-888-ASK-USGS (275-8747) DISCLAIMER Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Publication Date: February 2009