pkdiff - program to compare two raster image files
pkdiff
-i input -ref reference [options]
[advanced options]
pkdiff compares two datasets. The reference can either be a
raster or a vector, but the input must be a raster dataset. In case the
reference is a raster dataset, a pixel by pixel comparison is performed.
With no further options, the utility reports if the rasters are identical or
different. If required, an output raster dataset can be written with a
qualitative information per pixel: 0 (input=reference), 1
(input>reference) or 2 (input<reference). If, however, the reference
is a vector dataset, it must consist of point features. Polygon features are
automatically converted to the centroid points before analyzing.
A typical use of the utility is to assess the accuracy of an input
raster land cover map, based on a reference vector dataset. The reference
dataset must contain an attribute (label) for each class. A confusion matrix
is produced if the option -cm|--confusion is set. Here too, an
output dataset can be written, which will be a vector dataset in this case.
It contains the reference feature points with the extracted data value of
the raster input dataset as a new attribute.
- -i filename,
--input filename
- Input raster dataset.
- -ref filename,
--reference filename
- Reference (raster or vector) dataset
- -ln layer,
--ln layer
- Layer name(s) in sample. Leave empty to select all (for vector reference
datasets only)
- -b band, --band
band
- Input raster band
- -cm,
--confusion
- Create confusion matrix (to stdout)
- -lr attribute,
--lref attribute
- Attribute name of the reference label (for vector reference datasets
only)
- -c name,
--class name
- List of class names.
- -r value,
--reclass value
- List of class values (use same order as in classname option).
- -nodata
value, --nodata value
- No data value(s) in input or reference dataset are ignored
- -m mask, --mask
mask
- Use the first band of the specified file as a validity mask. Nodata values
can be set with the option --msknodata.
- -msknodata
value, --msknodata value
- Mask value(s) where image is invalid. Use negative value for valid data
(example: use -t -1: if only -1 is valid value)
- -v level,
--verbose level
- verbose level
Advanced options
- -o output,
--output output
- Output dataset (optional)
- -f OGRformat,
--f OGRformat
- OGR format for output vector (for vector reference datasets only)
- -of GDALformat,
--oformat GDALformat
- Output image format (see also gdal_translate(1)). Empty string:
inherit from input image
- -lc attribute,
--lclass attribute
- Attribute name of the classified label (for vector reference datasets
only)
- --commission
value
- Value for commission errors: input label < reference label
- -bnd value,
--boundary value
- Boundary for selecting the sample (for vector reference datasets
only)
- -hom,
--homogeneous
- Only take regions with homogeneous boundary into account (for reference
datasets only)
- -circ,
--circular
- Use circular boundary (for vector reference datasets only)
- -ct colortable,
--ct colortable
- Color table in ASCII format having 5 columns: id R G B ALFA (0:
transparent, 255: solid).
- -co NAME=VALUE,
--co NAME=VALUE
- Creation option for output file. Multiple options can be specified.
Check if two raster images are different (reports only if images
are different or not)
pkdiff -i input.tif -ref reference.tif
Validate a classification map using points from a reference sample
and report confusion matrix
pkdiff -i classificationMap.tif -ref referencePoints.tif -cm