pamdeinterlace(1) [minix man page]

pamdeinterlace(1)                                             General Commands Manual                                            pamdeinterlace(1)

NAME

       pamdeinterlace - remove ever other row from a PAM/PNM image

SYNOPSIS

       pamdeinterlace [-takeodd] [-takeeven] N [infile]

       You  can use the minimum unique abbreviation of the options.  You can use two hyphens instead of one.  You can separate an option name from
       its value with white space instead of an equals sign.

DESCRIPTION

       pamdeinterlace Removes all the even-numbered or odd-numbered rows from the input PNM or PAM image.  Specify which with  the  -takeeven  and
       -takeodd options.

       This  can  be useful if the image is a video capture from an interlaced video source.  In that case, each row shows the subject 1/60 second
       before or after the two rows that surround it.  If the subject is moving, this can detract from the quality of the image.

       Because the resulting image is half the height of the input image, you will then want to use pamstretch or pnmscale to restore  it  to  its
       normal height:

       pamdeinterlace myimage.ppm | pamstretch -yscale=2 >newimage.ppm

OPTIONS

       -takeodd
              Take  the  odd-numbered rows from the input and put them in the output.  The rows are numbered starting at zero, so the first row in
              the output is the second row from the input.  You cannot specify both -takeeven and -takeodd.

       -takeeven
              Take the even-numbered rows from the input and put them in the output.  The rows are numbered starting at zero, so the first row  in
              the output is the first row from the input.  This is the default.  You cannot specify both -takeeven and -takeodd.

SEE ALSO

       pamstretch(1), pnmscale(1)

AUTHOR

       put by Bryan Henderson in the public domain in 2001

                                                                 11 November 2001                                                pamdeinterlace(1)

pamstretch(1)						      General Commands Manual						     pamstretch(1)

NAME
       pamstretch - scale up a PNM or PAM image by interpolating between pixels

SYNOPSIS
       pamstretch [-xscale=X] [-yscale=Y]
       [-blackedge] [-dropedge] N [infile]

       You  can use the minimum unique abbreviation of the options.  You can use two hyphens instead of one.  You can separate an option name from
       its value with white space instead of an equals sign.

DESCRIPTION
       pamstretch scales up pictures by integer values, either vertically, horizontally, or both.  pamstretch differs from pnmscale and pnmenlarge
       in  that  when it inserts the additional rows and columns, instead of making the new row or column a copy of its neighbor, pamstretch makes
       the new row or column an interpolation between its neighbors.  In some images, this produces better looking output.

       To scale up to non-integer pixel sizes, e.g. 2.5, try pamstretch-gen(1) instead.

       Options let you select alternative methods of dealing with the right/bottom edges of the picture.  Since the interpolation is done  between
       the  top-left  corners of the scaled-up pixels, it's not obvious what to do with the right/bottom edges.  The default behaviour is to scale
       those up without interpolation (more precisely, the right edge is only interpolated vertically, and the bottom edge  is	only  interpolated
       horizontally), but there are two other possibilities, selected by the blackedge and dropedge options.

PARAMETERS
       The  N  parameter  is the scale factor.	It is valid only if you don't specify -xscale or -yscale.  In that case, pamstretch scales in both
       dimensions and by the scale factor N.

OPTIONS
       -xscale=X
	      This is the horizontal scale factor.  If you don't specify this, but do specify a vertical scale factor, the horizontal scale factor
	      is 1.

       -yscale=Y
	      This  is	the vertical scale factor.  If you don't specify this, but do specify a horizontal scale factor, the vertical scale factor
	      is 1.

       -blackedge
	      interpolate to black at right/bottom edges.
       -dropedge
	      drop one (source) pixel at right/bottom edges. This is arguably more logical than the default behaviour, but it means producing out-
	      put which is a slightly odd size.

BUGS
       Usually	produces  fairly  ugly	output	for PBMs. For most PBM input you'll probably want to reduce the `noise' first using something like
       pnmnlfilt(1).

SEE ALSO
       pamstretch-gen(1), pnmenlarge(1), pnmscale(1), pnmnlfilt(1)

AUTHOR
       Russell Marks (russell.marks@ntlworld.com).

								 11 November 2001						     pamstretch(1)