RCSTATS

Description

Outputs row or column image statistics to an array segment.

Parameters

Name	Type	Length	Value range
Input: Input raster channel *	Raster port	1 - 1
Exclude Values or Ranges	Float	0 - 16
Output Statistics Mode	String	0 - 1	Default: COLMEAN
Output: Output array segment	Array port	0 - 1
Output Layer Name	String	0 -
Output Layer Description	String	0 -
Image Mean	Real	0 - 1
Image Sum	Real	0 - 1
Standard Deviation	Real	0 - 1
Image Variance	Real	0 - 1
Lowest Gray Level	Real	0 - 1
Highest Gray Level	Real	0 - 1

* Required parameter

Parameter descriptions

Input: Input raster channel

Specifies the image channel to use to generate the row/column statistics.

Exclude Values or Ranges

Optionally specifies ranges of gray-level values to exclude when generating the row/column statistics. If this parameter is not specified, all gray levels in the image window are used.

Ranges are specified in pairs of values. In each pair, the first value is the beginning of the range and the second is the end of the range. The exception here is that, if there is an odd number of values, the last value is used as a range of one value.

For example:

EXCLUDE = 1,1,20,31.7,41.3

In this example, pixels with a gray-level value of 1 (that is, a range of 1 to 1) or in the range of 20 to 31.7, or a gray level of 41.3 (that is, a range of 41.3 to 41.3) are excluded.

Output Statistics Mode

Optionally specifies the row or column statistics to output. If this parameter is not specified, the only column means are output.

Output: Output array segment

Optionally specifies the number of the array segment to receive the row/column statistics. If this parameter is not specified, a new array segment (type 181) is created.

If an existing segment is to be overwritten but is too small to contain the output statistics, RCSTATS exits in error.

Output Layer Name

Optionally specifies a name (up to 8 characters) for the output segment, if one is created.

If this parameter is not specified, the default name "ARRAYOP" is used.

Output Layer Description

Optionally describes (in up to 64 characters) the contents or origins of the output array segment.

Image Mean

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the output image mean.

Image Sum

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the output image sum.

Standard Deviation

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the output image standard deviation.

Image Variance

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the output image variance.

Lowest Gray Level

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the lowest gray level in the output image.

Highest Gray Level

This is an output parameter and requires no user input.

Upon completion, RCSTATS writes to the output image statistics parameters information about the processed image.

This parameter receives the highest gray level in the output image.

Details

RCSTATS generates column or row image statistics and writes them to an array segment. The operations available for columns or rows are means, sums, standard deviations, variances, minimums, or maximums.

You may also specify values to exclude when generating the statistics, using the EXCLUDE parameter. If this parameter is not specified, all gray levels in the image window are processed.

You may specify an existing array segment (ARRSEG) to overwrite. Note, however, that if the existing segment is too small to contain the output statistics, RCSTATS will exit in error.

If the output array segment is not specified, a new array segment is created and appended to the end of the input file. If a new array segment is created, the segment name (DBSN) and description (DBSD) can be be specified.

RCSTATS writes the image statistics to the output parameters.

Statistics

Only image data in the image window (DBIW) and outside the exclusion range (EXCLUDE) is used as input to the statistics. For example, the column statistics available are:

COLMEAN	=	sum(  graylevels ) / count
COLSUM	=	sum(  graylevels )
COLSD	=	sqrt( sum( (graylevel - COLMEAN)**2 ) / (count - 1) )
COLVAR	=	sum( (graylevel - COLMEAN)**2 ) / (count - 1)
COLMIN	=	min(  graylevels )
COLMAX	=	max(  graylevels )

The row statistics apply to the discussion above by substituting ROW for COL and "row" for "column". The image statistics output to the IMSTAT parameter apply by substituting "image" for "column".