---
name: "pgmabel"
section: "1"
platform: "linux"
package: "netpbm"
version: "10.86.51-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/pgmabel"
---

# pgmabel(1)

create cross section using Abel Integration for Deconvolution

## NAME

pgmabel - create cross section using Abel Integration for Deconvolution

## SYNOPSIS

**pgmabel** \[**-help**\] \[**-axis** *axis*\] \[**-factor** *factor*\] \[**-pixsize** *pixsize*\] \[**-left** \| **-right**\] \[**-verbose**\] \[*filespec*\]

## DESCRIPTION

This program is part of **Netpbm**(1) .

**pgmabel** reads as input a PGM image, which it assumes to be an image of a rotational symmetric transparent object.  The image must have a vertical symmetry axis.  **pgmabel** produces as output an image of a cross-section of the image.

**pgmabel** does the calculation by performing the Abel Integration for Deconvolution of an axial-symmetrical image by solving the system of linear equations.

After integration, **pgmabel** weights all gray-values of one side by the surface area of the calculated ring in square pixels divided by 4\**factor* multiplied by the size of one pixel (*pixsize*). With the **-verbose** option, **pgmabel** prints the weighting factors.

Where the calculation generates a negative result, the output is black.

The computation is unstable against periodic structures with size 2 in the vertical direction.

## OPTIONS

In addition to the options common to all programs based on libnetpbm (most notably **-quiet**, see \
  Common Options ⟨index.html#commonoptions⟩ ), **pgmabel** recognizes the following command line options:

You can abbreviate any option to its shortest unique prefix.

- **-help**

  Prints a help message.

- **-axis** *axis*

  Position of the axis of symmetry in the image in pixels from the left edge of the image.  Default is the center of the image.

- **-factor** *factor*

  User defined factor for enhancement of the output.  Use a *factor* less than 1 for decreasing gary values.  Default is 1.0.

- **-pixsize** *pixsize*

  The size of a pixel for getting scale invariant.  Default is 0.1.

- **-left**

  Calculate only the left side of the image.  You cannot specify both **left** and **right**.

- **-right**

  Analogous to **-left**.

- **-verbose**

  print information about the calculation.

## EXAMPLE

Rotate a PGM image to get an image with a vertical axis of symmetry, then calculate the cross section:

```
    pnmrotate 90 file.pgm | pgmabel -axis 140 >cross_section.pgm
```

## SEE ALSO

[**pnmrotate**(1)](/pnmrotate/1.md) , **pgm**(1) ,

## HISTORY

This program was added to Netpbm in Release 10.3 (June 2002).

## AUTHOR

Volker Schmidt (lefti@voyager.boerde.de)

Copyright (C) 1997-2002 German Aerospace research establishment

## DOCUMENT SOURCE

This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The master documentation is at

-

  **http://netpbm.sourceforge.net/doc/pgmabel.html**