'''ossim-preproc'''

Used to create reduced resolution data sets, histograms, and so on. Application does directory walking and is threaded at a file level. 

'''Usage:'''



{{{
$ ossim-preproc
Usage: ossim-preproc [options] <file-or-directory-to-walk>
Options:
  --ch or --create-histogram        Computes full histogram alongside overview.
  --chf or --create-histogram-fast  Computes a histogram in fast mode which
                                    samples partial tiles.
  --compression-quality             Compression quality for TIFF JPEG takes
                                    values from 0 to 100, where 100 is best. 
                                    For J2K plugin, numerically_lossless,
                                    visually_lossless, lossy
  --compression-type                Compression type can be: deflate, jpeg, lzw,
                                    none or packbits
  --create-histogram-r0             Forces create-histogram code to compute a
                                    histogram using r0 instead of the starting
                                    resolution for the overview builder. Can
                                    require a separate pass of R0 layer if the
                                    base image has built in overviews.
  --disable-elev                    Will disable the elevation
  --disable-notify                  Takes an argument. Arguments are ALL, WARN,
                                    NOTICE, INFO, FATAL, DEBUG.  If you want
                                    multiple disables then just do multiple
                                    --disable-notify on the command line.  All
                                    argument are case insensitive.  Default is
                                    all are enabled.
  --disable-plugin                  Will disable the plugin loader
  --list-entries                    Lists the entries within the image
  --of or --output-files            Output image files we can open, exluding
                                    overviews.
  --ossim-logfile                   takes a logfile as an argument.  All output
                                    messages are redirected to the specified log
                                    file.  By default there is no log file and
                                    all messages are enabled.
  --ot                              <overview_type> Overview type. see list at
                                    bottom for valid types.
                                    (default=ossim_tiff_box)
  --reader-prop                     Adds a property to send to the reader.
                                    format is name=value
  --rebuild-histogram               Rebuild histogram even if they are already
                                    present.
  --scanForMinMax                   Turns on min, max scanning when reading
                                    tiles. This option assumes the null is
                                    known.
  --scanForMinMaxNull               Turns on min, max, null scanning when
                                    reading tiles.  This option tries to find a
                                    null value which is useful for float data.
  --threads                         <threads> The number of threads to use.
                                    (default=1) Note a default can be set in
                                    your ossim preferences file by setting the
                                    key "ossim_threads".
  --tile-size                       <size> Defines the tile size for overview
                                    builder.  Tiff option only. Must be a
                                    multiple of 16. Size will be used in both x
                                    and y directions. Note a default can be set
                                    in your ossim preferences file by setting
                                    the key "tile_size".
  --writer-prop                     Adds a property to send to the writer.
                                    format is name=value
  -K                                specify individual keywords to add to the
                                    preferences keyword list: name=value
  -P                                specify a preference file to load
  -T                                specify the classes to trace, ex:
                                    ossimInit|ossimImage.* 
                                    will trace ossimInit and all ossimImage
                                    classes
  -V or --version                   Display version information.
  -a or --include-fullres           Copy full res dataset to overview file as
                                    well as building reduced res sets. Option
                                    only valid with tiff overview builder.
                                    Requires -o option.
  -d                                <output_directory> Write overview to output
                                    directory specified.
  -h                                Display this information
  -o                                Creates overviews. (default=ossim_tiff_box)
  -r or --rebuild-overviews         Rebuild overviews even if they are already
                                    present.
  -s                                Stop dimension for overviews.  This controls
                                    how 
                                    many layers will be built. If set to 64 then
                                    the builder will stop when height and width
                                    for current level are less than or equal to
                                    64.  Note a default can be set in the ossim
                                    preferences file by setting the keyword
                                    "overview_stop_dimension".


Valid overview types: 
ossim_tiff_box	
ossim_tiff_nearest	
ossim_kakadu_nitf_j2k	
gdal_tiff_nearest	
gdal_tiff_average	
gdal_hfa_nearest	
gdal_hfa_average	

Example commands:

// A single image standard tiff overviews, histogram:
ossim-preproc -o --ch <file>

// A single image with j2k overviews(requires kakadu plugin), histogram:
ossim-preproc --ot ossim_kakadu_nitf_j2k --ch <file>

// j2k, histogram, 4 threads

// standard tiff overviews, full histogram, 4 threads:
ossim-preproc -r -o --ch --threads 4 <directory_to_walk>

// j2k, histogram (fast mode), 4 threads
ossim-preproc -r --ot ossim_kakadu_nitf_j2k --chf --threads 4 <directory_to_walk>

// tiff, jpeg compression, histogram, 4 threads
ossim-preproc -r --ch --compression-quality 75 --compression-type jpeg --threads 4 <directory_to_walk>

NOTES:

  --ch  equals --create-histogram
  --chf equals --create-histogram-fast

}}}