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USGS/EROS Archive Preservation Status Update Stuart Doescher, USGS (Cheryl Greenhagen) W GISS – 22 Sept 11- 15, 2006 Annapolis, MD USA. TM and MSS Archive Conversion System (TMACS). Operations: 1992 to 2002. Number of High Density Tapes (HDT) transcribed: 55,503 Landsat MSS, TM
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USGS/EROS Archive Preservation Status Update Stuart Doescher, USGS (Cheryl Greenhagen) WGISS – 22 Sept 11- 15, 2006 Annapolis, MD USA
TM and MSS Archive Conversion System (TMACS) • Operations: 1992 to 2002. • Number of High Density Tapes (HDT) transcribed: 55,503 • Landsat MSS, TM • Number of DCRSi Cassette Tapes (DCT)s output: 3,827 • Mostly in Telemetry stream format (Frame sync required to read)
WBVT summary • Operated: April 1999 - May 2002 • Number of HDTs converted: 21,300 • Number of Digital Linear Tape (DLT 7000) generated: 143 and an additional 143 as backup • Format: BSQ ( MSS-X) • "orphan" data (no DIAT / SLAT) save on 172 DLTs • Bad input tapes: 476 (even with cleaning & baking).
SPOT summary • Operated: late April 2000 - February 2002 • Number of HDTs converted: 6,100 • Number of DLT 7000 tapes generated: 901 • Format: MDA's FRED
Landsat Archive Conversion System (LACS) • Planned Operations: June 2004 – December 2006 • Input: About 5500 HDTs, 4000 DCTs, plus current Landsat 5 data • Output: ~ 1100 tapes of "formatted" data and ~ 1200 tapes of "raw" data on 9940B. (~180G/tape) • Format: BSQ
LACS Description • Ingest current Landsat 5 data from disk files • Ingest data from DCRSi Cassette Tapes (DCTs) • Multispectral Scanner Archive format (MSS-A) data • Multispectral Scanner Product format (MSS-P) data • Thematic Mapper Archive format (TM-A) data • Thematic Mapper raw (TM-R) data • Ingest TM-R data from High Density Tapes (HDTs) • Archive the data to a high-density computer-compatible digital tape: 9940B • Generate and archive browse imagery • Generate inventory information for the new archive.
LACS Status • Started Operations: June 2004 • Progress to Date: (July 31, 2006) • TM-R DCTs complete (3,320 DCTs, 555,000 scenes) • TM-R HDTs complete (5,444 HDTs, 112,000 scenes) • TM-A DCTs complete (108 DCTs, 17,000 scenes) • TM-R New Landsat 5 Data (86,000 scenes) • MSS-A started (21 DCTs, 17,000 scenes) • Transcription rate will decrease as we handle more data anomalies and problem tapes • Estimated completion: December 2006
LACS Status • LTS (LACS Transcription Subsystem) 4 Strings: • LTS1: Current Landsat 5 data (acquired at EDC or GLC, or received on DLT from Australia) • LTS2: DCT Input (2 shifts per day, 5 days a week) • LTS3: DCT Input (2 shifts per day, 5 days a week) • LTS4: DCT Input (2 shifts per day, 7 days a week)
LACS Status • LIS (LACS Integration Subsystem) Performs Automated Cloud Cover Assessment, Browse Generation, Quality Assignment Provides Interactive Assessment Capability Gives priority to current Landsat 5 data LIS work is distributed across 3 strings
LACS Status • Issues / Problems: • Data anomalies, tape degradation, cross-play issues • DCRSi tape drives require frequent cleaning and maintenance • Plans: • Complete tape transcription • Port LTS from SGI to Intel (Linux)