[FWTools] MrSID Reader performance?

[Jason Birch]

Hi all,

I'm converting a few MrSID images out into TIFFs with a reduced
resolution.  The first four went extremely fast, but the last one (which
is the second-largest) is taking forever, and from the  page faulting
like crazy.

Is there something about the dimensions of this image (100000x105000) or
size (1,149,185,743 b) that would be causing this?  Another one that I
just ran had a slightly larger size (by about 25 MB) but was a lot
faster.

Is there an environment variable that I can tweak to give this more
horsepower? :)

FWTools 1.1.3
Windows XP
2.8GHz Pentium D
3GB RAM

gdalinfo output:

Driver: MrSID/Multi-resolution Seamless Image Database (MrSID)
Size is 100000, 105000
Coordinate System is `'
Origin = (427000.000000000000000,5455000.000000000000000)
Pixel Size = (0.100000000000000,-0.100000000000000)
Metadata:
 
IMAGE__INPUT_NAME=R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pas
s\NE\252c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\252d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\352a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\352b.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\352c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\352d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\353a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\353c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\452a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\452b.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\452c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\452d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\453a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\453c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\453d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\552a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\552b.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\552c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\552d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\553a.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\553b.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\553c.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\553d.tif,
R:\Work\17580-0_Nanaimo-Ortho\Ortho\LOW\OV\bal\out\pass\NE\554c.tif
  IMAGE__INPUT_FILE_SIZE=21602844171.000000
  IMAGE__COMPRESSION_VERSION=1,3,0
  IMAGE__TARGET_COMPRESSION_RATIO=20.000000
  IMAGE__COMPRESSION_NLEV=8
  IMAGE__COMPRESSION_WEIGHT=4.000000
  IMAGE__COMPRESSION_GAMMA=2.000000
  IMAGE__COMPRESSION_BLOCK_SIZE=2048
  IMAGE__CREATION_DATE=Fri Nov 10 21:12:58 2006

  IMAGE__WIDTH=100000
  IMAGE__HEIGHT=105000
  IMAGE__NO_DATA_VALUE=255,255,255
  IMAGE__COLOR_SCHEME=0
  IMAGE__DATA_TYPE=0
  IMAGE__BITS_PER_SAMPLE=8
  IMAGE__XY_ORIGIN=427000.050000,5454999.950000
  IMAGE__X_RESOLUTION=0.100000
  IMAGE__Y_RESOLUTION=0.100000
Corner Coordinates:
Upper Left  (  427000.000, 5455000.000) 
Lower Left  (  427000.000, 5444500.000) 
Upper Right (  437000.000, 5455000.000) 
Lower Right (  437000.000, 5444500.000) 
Center      (  432000.000, 5449750.000) 
Band 1 Block=1024x128 Type=Byte, ColorInterp=Red
  Overviews: 50000x52500, 25000x26250, 12500x13125, 6250x6563,
3125x3282, 1563x1641, 782x821, 391x411
Band 2 Block=1024x128 Type=Byte, ColorInterp=Green
  Overviews: 50000x52500, 25000x26250, 12500x13125, 6250x6563,
3125x3282, 1563x1641, 782x821, 391x411
Band 3 Block=1024x128 Type=Byte, ColorInterp=Blue
  Overviews: 50000x52500, 25000x26250, 12500x13125, 6250x6563,
3125x3282, 1563x1641, 782x821, 391x411

Jason