nearblack(1) [debian man page]

nearblack(1)						      General Commands Manual						      nearblack(1)

NAME

       nearblack - nearblack convert nearly black/white borders to black

SYNOPSIS

       nearblack [-of format] [-white | [-color c1,c2,c3...cn]*] [-near dist] [-nb non_black_pixels]
		 [-setalpha] [-setmask] [-o outfile] [-q]  [-co "NAME=VALUE"]* infile

DESCRIPTION

       This utility will scan an image and try to set all pixels that are nearly or exactly black, white or one or more custom colors around the
       collar to black or white. This is often used to 'fix up' lossy compressed airphotos so that color pixels can be treated as transparent when
       mosaicing.

       -o outfile:
	   The name of the output file to be created. Newly created files are created with the HFA driver by default (Erdas Imagine - .img)

       -of format:
	   (GDAL 1.8.0 or later) Select the output format. Use the short format name (GTiff for GeoTIFF for examle).

       -co 'NAME=VALUE':
	   (GDAL 1.8.0 or later) Passes a creation option to the output format driver. Multiple -co options may be listed. See format specific
	   documentation for legal creation options for each format. Only valid when creating a new file

       -white:
	   Search for nearly white (255) pixels instead of nearly black pixels.

       -color c1,c2,c3...cn:
	   (GDAL >= 1.9.0) Search for pixels near the specified color. May be specified multiple times. When -color is specified, the pixels that
	   are considered as the collar are set to 0.

       -near dist:
	   Select how far from black, white or custom colors the pixel values can be and still considered near black, white or custom color.
	   Defaults to 15.

       -nb non_black_pixels:
	   number of non-black pixels that can be encountered before the giving up search inwards. Defaults to 2.

       -setalpha:
	   (GDAL 1.8.0 or later) Adds an alpha band if the output file is specified and the input file has 3 bands, or sets the alpha band of the
	   output file if it is specified and the input file has 4 bands, or sets the alpha band of the input file if it has 4 bands and no output
	   file is specified. The alpha band is set to 0 in the image collar and to 255 elsewhere.

       -setmask:
	   (GDAL 1.8.0 or later) Adds a mask band to the output file, or adds a mask band to the input file if it does not already have one and no
	   output file is specified. The mask band is set to 0 in the image collar and to 255 elsewhere.

       -q:
	   (GDAL 1.8.0 or later) Suppress progress monitor and other non-error output.

       infile:
	   The input file. Any GDAL supported format, any number of bands, normally 8bit Byte bands.

       The algorithm processes the image one scanline at a time. A scan 'in' is done from either end setting pixels to black or white until at
       least 'non_black_pixels' pixels that are more than 'dist' gray levels away from black, white or custom colors have been encountered at
       which point the scan stops. The nearly black, white or custom color pixels are set to black or white. The algorithm also scans from top to
       bottom and from bottom to top to identify indentations in the top or bottom.

       The processing is all done in 8bit (Bytes).

       If the output file is omitted, the processed results will be written back to the input file - which must support update.

AUTHORS

       Frank Warmerdam warmerdam@pobox.com

GDAL
								  Tue Sep 18 2012						      nearblack(1)

gdal_translate(1)					      General Commands Manual						 gdal_translate(1)

NAME

       gdal_translate - gdal_translate converts raster data between different formats

SYNOPSIS

       gdal_translate [--help-general]
	      [-ot {Byte/Int16/UInt16/UInt32/Int32/Float32/Float64/
		    CInt16/CInt32/CFloat32/CFloat64}] [-strict]
	      [-of format] [-b band] [-mask band] [-expand {gray|rgb|rgba}]
	      [-outsize xsize[%] ysize[%]]
	      [-unscale] [-scale [src_min src_max [dst_min dst_max]]]
	      [-srcwin xoff yoff xsize ysize] [-projwin ulx uly lrx lry]
	      [-a_srs srs_def] [-a_ullr ulx uly lrx lry] [-a_nodata value]
	      [-gcp pixel line easting northing [elevation]]*
	      [-mo "META-TAG=VALUE"]* [-q] [-sds]
	      [-co "NAME=VALUE"]* [-stats]
	      src_dataset dst_dataset

DESCRIPTION

       The gdal_translate utility can be used to convert raster data between different formats, potentially performing some operations like
       subsettings, resampling, and rescaling pixels in the process.

       -ot: type
	   For the output bands to be of the indicated data type.

       -strict:
	   Do'nt be forgiving of mismatches and lost data when translating to the output format.

       -of format:
	   Select the output format. The default is GeoTIFF (GTiff). Use the short format name.

       -b band:
	   Select an input band band for output. Bands are numbered from 1. Multiple -b switches may be used to select a set of input bands to
	   write to the output file, or to reorder bands. Starting with GDAL 1.8.0, band can also be set to 'mask,1' (or just 'mask') to mean the
	   mask band of the 1st band of the input dataset.

       -mask band:
	   (GDAL >= 1.8.0) Select an input band band to create output dataset mask band. Bands are numbered from 1. band can be set to 'none' to
	   avoid copying the global mask of the input dataset if it exists. Otherwise it is copied by default ('auto'), unless the mask is an
	   alpha channel, or if it is explicitely used to ben a regular band of the output dataset ('-b mask'). band can also be set to 'mask,1'
	   (or just 'mask') to mean the mask band of the 1st band of the input dataset.

       -expand gray|rgb|rgba:
	   (From GDAL 1.6.0) To expose a dataset with 1 band with a color table as a dataset with 3 (RGB) or 4 (RGBA) bands. Usefull for output
	   drivers such as JPEG, JPEG2000, MrSID, ECW that don't support color indexed datasets. The 'gray' value (from GDAL 1.7.0) enables to
	   expand a dataset with a color table that only contains gray levels to a gray indexed dataset.

       -outsize xsize[%] ysize[%]:
	   Set the size of the output file. Outsize is in pixels and lines unless '' is attached in which case it is as a fraction of the input
	   image size.

       -scale [src_min src_max [dst_min dst_max]]:
	   Rescale the input pixels values from the range src_min to src_max to the range dst_min to dst_max. If omitted the output range is 0 to
	   255. If omitted the input range is automatically computed from the source data.

       -unscale:
	   Apply the scale/offset metadata for the bands to convert scaled values to unscaled values. It is also often necessary to reset the
	   output datatype with the -ot switch.

       -srcwin xoff yoff xsize ysize:
	   Selects a subwindow from the source image for copying based on pixel/line location.

       -projwin ulx uly lrx lry:
	   Selects a subwindow from the source image for copying (like -srcwin) but with the corners given in georeferenced coordinates.

       -a_srs srs_def:
	   Override the projection for the output file. The srs_def may be any of the usual GDAL/OGR forms, complete WKT, PROJ.4, EPSG:n or a file
	   containing the WKT.

       -a_ullr ulx uly lrx lry:
	   Assign/override the georeferenced bounds of the output file. This assigns georeferenced bounds to the output file, ignoring what would
	   have been derived from the source file.

       -a_nodata value:
	   Assign a specified nodata value to output bands. Starting with GDAL 1.8.0, can be set to none to avoid setting a nodata value to the
	   output file if one exists for the source file

       -mo 'META-TAG=VALUE':
	   Passes a metadata key and value to set on the output dataset if possible.

       -co 'NAME=VALUE':
	   Passes a creation option to the output format driver. Multiple -co options may be listed. See format specific documentation for legal
	   creation options for each format.

       -gcp pixel line easting northing elevation:
	   Add the indicated ground control point to the output dataset. This option may be provided multiple times to provide a set of GCPs.

       -q:
	   Suppress progress monitor and other non-error output.

       -sds:
	   Copy all subdatasets of this file to individual output files. Use with formats like HDF or OGDI that have subdatasets.

       -stats:
	   (GDAL >= 1.8.0) Force (re)computation of statistics.

       src_dataset:
	   The source dataset name. It can be either file name, URL of data source or subdataset name for multi-dataset files.

       dst_dataset:
	   The destination file name.

EXAMPLE

       gdal_translate -of GTiff -co "TILED=YES" utm.tif utm_tiled.tif

       Starting with GDAL 1.8.0, to create a JPEG-compressed TIFF with internal mask from a RGBA dataset :

       gdal_translate rgba.tif withmask.tif -b 1 -b 2 -b 3 -mask 4 -co COMPRESS=JPEG -co PHOTOMETRIC=YCBCR --config GDAL_TIFF_INTERNAL_MASK YES

       Starting with GDAL 1.8.0, to create a RGBA dataset from a RGB dataset with a mask :

       gdal_translate withmask.tif rgba.tif -b 1 -b 2 -b 3 -b mask

AUTHORS

       Frank Warmerdam warmerdam@pobox.com, Silke Reimer silke@intevation.de

GDAL
								  Tue Sep 18 2012						 gdal_translate(1)