[Gdal-dev] RE: Kakadu georeferencing

[Frank Warmerdam]

Gerald Buckmaster wrote:

> Frank,
> 
> This is a bit off-topic, development-wise, but the thread touched off a 
> question.
> 
> I am using geotifcp, and gdal_translate.exe with Kakadu to georeference and 
> compress BMP files, first converting the BMP to a regular TIF, then TIF to 
> GeoTIFF, and finally GeoTIFF to JP2 format.  I use a VBScript to do the 
> number crunching and passing of variables to the executables for processing.  
> Is there a way I can go straight from BMP to JP2 using only a geotiff tag, 
> like the one below, without the 2 intermediate conversion steps?  I'm looking 
> to reduce the processing time per image (currently 60 seconds per 82mb BMP 
> file)?
> 
> v/r
> 
> Buck
> 
> Geotiff_Information:
> Version: 1
> Key_Revision: 1.0
> Tagged_Information:
> ModelTransformationTag(4,4):
> 3.17756913644005E-07 1.56182512826881E-06 0 -147.895661114049
> 1.56182512826881E-06 -3.17756913644005E-07 0 33.2643388859509
> 0 0 0 0
> 0 0 0 1
> End_Of_Tags.
> Keyed_Information:
> GTModelTypeGeoKey (Short,1): ModelTypeGeographic
> GTRasterTypeGeoKey (Short,1): RasterPixelIsArea
> GeographicTypeGeoKey (Short,1): GCS_WGS_84
> End_Of_Keys.
> End_Of_Geotiff.

Gerald,

You can do the translation in one step using gdal_translate if you write
out your ModelTransformationTag info to a .wld file along side the .bmp file.
Assuming your .bmp has the appropriate .wld the following command would
translate to JP2 format with the WGS84 LL coordinate system:

   gdal_translate -a_srs WGS84 -of JP2KAK input.bmp output.jp2

Hopefully the world file format is pretty obvious, but one easy way to
verify the correct argument order is to run the "listgeo" utility with the
-tfw flag against a geotiff file and a corresponding world file (with the
.tfw extension) will be written out.  From that you can ensure you know what
order to put in the coefficients.

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    | Geospatial Programmer for Rent