Post on 19-Jan-2016
USGS/EROSArchive Preservation
StatusUpdate
Stuart Doescher, USGS
(Cheryl Greenhagen)WGISS – 22
Sept 11- 15, 2006Annapolis, MD USA
TM and MSS Archive Conversion TM and MSS Archive Conversion System (TMACS)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 summaryWBVT 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 summarySPOT 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 DescriptionLACS 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.
Data to be converted by LACSData to be converted by LACS
Data SetNumber of
ScenesNumber of
Tapes Data Volume
MSS-P 65,128 118 DCTs 3.2 terabytes
MSS-A 262,088 277 DCTs 9.5 terabytes
TM-A 17,000 108 DCTs 3.6 terabytes
TM-R (1982 – 2005) 550,000 3,320 DCTs 140 terabytes
TM-R (1995 – 2002) 97,250 5,444 HDTs 27.0 terabytes
TM-R (new) ~ 14 terabytes
1,031,762 Total ~200 terabytes
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 Configuration
LACS1LTS 1: R C C Ingest
LACS3LTS 3: D C T Ingest
LACS2LTS 2: D C T Ingest
LAM
DCS
LIS 1D isk
SAN
LA C S 3D isk
LIS1LIS 1: D B ,
B rowse / A C C A
LIS2LIS 2: B rowse /
A C C A
LIS3LIS 3: B rowse /
A C C A
LCDSLA C S D BD C S D B
LACS4LTS 4: D C T Ingest
SILOLocal
D B linkSANnfs
LACS StatusLACS 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 StatusLACS 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)