Landsat Metadata (MTL) files contain beneficial information for the systematic searching and archiving practices of data. Information about data processing and values important for enhancing Landsat data (such as conversion to reflectance and radiance) are also included in this file. Data Format Control Books (DFCB) define and describe Landsat metadata. DFCB for all sensors can be found on http://landsat.usgs.gov/tools_project_documents.php.
Below are details of major changes made to MTL files that affect usage, as well as any changes made to the Landsat filenames. The changes to the MTL may affect parsing of information as well as scripting done with various software packages.
July 23, 2014 – Ground control points versioning to be added to MTL file
The version number of the GCPs used to register an image will be recorded in the MTL file following the next processing system release in September 2014. The Landsat Project is improving the ground control points (GCPs) used to georegister Landsat products.
The much higher geolocation accuracy of Landsat 8 makes it possible to significantly improve the absolute accuracy of Landsat data products for all Landsat sensors. For more information about the phased GCP Improvement Plan with details on the Phase 1 GCPs to be released in September, please see the July 1, 2014, headlines at http://landsat.usgs.gov/mission_headlines2014.php.
The new metadata parameter will only be provided for any scene that processes to a Level 1 Precision and Terrain-Corrected (L1T) product (PRODUCT_TYPE = "L1T"). The metadata parameter names for the GCP versioning are provided below:
Group name: IMAGE_ATTRIBUTES
Parameter name: GROUND_CONTROL_POINTS_VERSION
GCP versioning and the release of the Phase 1 GCPs take effect with Landsat Level 1 Product Generation System (LPGS) releases identified below and all future releases:
PROCESSING_SOFTWARE_VERSION = “LPGS_2.4.0” for Landsat 8 products
PROCESSING_SOFTWARE_VERSION = "LPGS_12.5.0" for Landsat 1-7 products
L1T products created in prior releases will not have the versioning field. See the Landsat L1 Data Format Control Books (DFCB) for more information about the MTL files (http://landsat.usgs.gov/tools_project_documents.php).
Users can use the GCP version in combination with GCP release notes to determine which scenes are impacted with each version number. A list of the 171 path/rows with GCPs updated in GCP Improvement Phase 1 (GROUND_CONTROL_POINTS_VERSION =”2”) can be found here.
All images for path/rows updated in Phase 1 will be removed from the online storage and will be reprocessed. We recommend reordering all images associated with Phase 1 path/rows. Guidance for future releases will be provided at the time of their release.
July 9, 2014 – Extra Lines to be removed at the end of the MTL file
The extra lines (padding) that are currently at the end of the MTL file, which were historically used to distribute a fixed-size file to support the HDF4 format, will be removed in September,2 014. Since GeoTIFF is now the only data format provided, the bytes at the end of the file are not needed, and the extra lines will be removed. Samples of the modified MTL files are available to download from http://landsat.usgs.gov/documents/remtlpaddingchangestexttoreview.zip. (4.77 KB)
April 25, 2013 – Old Metadata Format to be removed
For over 6 months, Landsat 1-7 products have included a new metadata format to align with operational data from the Landsat Data Continuity Mission. We have been including the historic metadata format to allow users enough transition time to adjust to the new format. That file, *_OLD.txt, will be removed as of Monday, April 29, 2013.
August 29, 2012 - Landsat metadata and filename changes
On August 29, 2012, metadata files and filenames associated with Landsat Level 1 Products changed. Modifications were made to make filenames, metadata fields, and files consistent for all sensors, including Landsat 8 data products.
The historical metadata files were renamed to end in _MTLold.txt. The new files end in the standard _MTL.txt. Effective April 29, 2013, any Landsat scene processed includes only the _MTL.txt. Some scenes will have two files until the data is removed from downloadable status and reprocessed.
The files below list the ordering and field names of the current metadata in the first column, and the ordering and field names of the new metadata in the second column for each sensor. Each field name is identified as 'No change', 'Removed', 'Name update', or 'Added'. For each 'Name update', an explanation of the change is provided.
ETM+ Metadata Changes - .pdf (241 KB)
TM Metadata Changes - .pdf (226 KB)
MSS Metadata Changes - .pdf (227 KB)