[FWTools] ESRI JPG/ with JGW files conversion

[Frank Warmerdam]

Shaun Kolomeitz wrote:
> Dear Listers,
> 
> I have struck a problem converting a JPG file with an ESRI world file (JGW) and trying to maintain the position of the image in "real world" coordinates.
> When I do a GDALINFO on the images for example -
> 
> Z:\image\9541\0.6>gdalinfo 9541-1122.jpg
> Driver: JPEG/JPEG JFIF
> Size is 1608, 3227
> Coordinate System is `'
> Corner Coordinates:
> Upper Left  (    0.0,    0.0)
> Lower Left  (    0.0, 3227.0)
> Upper Right ( 1608.0,    0.0)
> Lower Right ( 1608.0, 3227.0)
> Center      (  804.0, 1613.5)
> Band 1 Block=1608x1 Type=Byte, ColorInterp=Red
> Band 2 Block=1608x1 Type=Byte, ColorInterp=Green
> Band 3 Block=1608x1 Type=Byte, ColorInterp=Blue
> 
> This is despite a JGW (world file) existing.
> As such when I try to translate the image it loses the appropriate conversion parameters listed in the JGW file.
> 
> Any suggestions on how I could convert these files using GDAL commands ?

Shaun,

This *should* work.

For instance:

warmerda at gdal2200[277]% ls -l utm*
-rw-r--r--  1 warmerda users     98 Sep 11  2005 utm.jgw
-rw-r--r--  1 warmerda users 104905 May  1  2001 utm.jpg
warmerda at gdal2200[278]% gdalinfo utm.jpg
Driver: JPEG/JPEG JFIF
Size is 512, 512
Coordinate System is `'
Origin = (440720.000000,3751320.000000)
Pixel Size = (60.00000000,-60.00000000)
Corner Coordinates:
Upper Left  (  440720.000, 3751320.000)
Lower Left  (  440720.000, 3720600.000)
Upper Right (  471440.000, 3751320.000)
Lower Right (  471440.000, 3720600.000)
Center      (  456080.000, 3735960.000)
Band 1 Block=512x1 Type=Byte, ColorInterp=Gray

Is there any chance that your .jgw files name is actually different
in some subtle way - perhaps one of the "1"s is an "l" or something
like that?

Is it possible that Z: is a unix network drive and is case
sensitive?  If so try renaming everything to be lower case.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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and watch the world go round - Rush    | President OSGF, http://osgeo.org