- pamstereogram
--Updated: 10 May 2020
--
--Table Of Contents
-+
-+Updated: 10 May 2020
-+
-+Table Of Contents
-+
-
- NAME
-
--pamstereogram - create a single-image stereogram from a PAM depth map
-+pamstereogram - create a single-image stereogram from a PAM
-+depth map
-
- SYNOPSIS
-
-@@ -38,13 +41,13 @@ pamstereogram - create a single-image stereogram from a PAM depth map
- [-randomseed=integer]
- [-tileable]
- [infile]
--
-+
-
-
-
- DESCRIPTION
-
--This program is part of Netpbm.
-+
This program is part of Netpbm.
-
- pamstereogram inputs a depth map (a map of the distances
- from your eye of the points in a scene) and outputs a single-image
-@@ -54,22 +57,22 @@ eyes. What's exciting about single-image stereograms is that they
- don't require special glasses to view, although it does require a bit
- of practice to train your eyes to unfocus properly. The
- pamstereogram program provides a wealth of control over how the
--stereogram is generated, including the following:
-+stereogram is generated, including the following:
-
-
--- black and white, grayscale, or color output
-+
- black and white, grayscale, or color output
-
- - single-image random-dot stereograms (SIRDS), single-image
- stereograms (SIS) using a tiled image, or mapped-texture stereograms
--(MTS)
-+(MTS)
-
--- images targeting a given device resolution and eye separation
-+
- images targeting a given device resolution and eye separation
-
--- optional guide boxes to assist in focusing
-+
- optional guide boxes to assist in focusing
-
--- the ability to trade off depth levels for easier viewing
-+
- the ability to trade off depth levels for easier viewing
-
--- choice of wall-eyed or cross-eyed stereograms
-+
- choice of wall-eyed or cross-eyed stereograms
-
-
- The output is a PAM image on standard output. Options control
-@@ -79,7 +82,7 @@ if you will use the image as input to a current Netpbm program, but
- many other programs don't know what a PAM is.
-
-
To make a red/green type of stereogram (that you view with 3-D
--glasses) instead, see ppm3d.
-+glasses) instead, see ppm3d.
-
-
- OPTIONS
-@@ -87,36 +90,36 @@ glasses) instead, see ppm3d.
- In addition to the options common to all programs based on libnetpbm
- (most notably -quiet, see
- Common Options), pamstereogram recognizes the following
--command line options:
-+command line options:
-
- You may use either single or double hyphens to denote options. You
- may use either whitespace or an equals sign to separate an option name
--from its value.
-+from its value.
-
-
-
--- -verbose
-+
- -verbose
- - Display messages about image sizes and formats and properties
--of the stereogram being generated.
-+of the stereogram being generated.
-
--- -blackandwhite
-+
- -blackandwhite
- - Produce a single-image random-dot black-and-white stereogram.
--This is the default.
-+This is the default.
-
--- -grayscale
--
- Produce a single-image random-dot grayscale stereogram.
-+
- -grayscale
-+- Produce a single-image random-dot grayscale stereogram.
-
--- -color
--
- Produce a single-image random-dot color stereogram.
-+
- -color
-+- Produce a single-image random-dot color stereogram.
-
--- -maxval=value
-+
- -maxval=value
- - Designate the maximum value of each gray/color component, i.e.
- the color resolution. Smaller values make the output image have
- smaller numbers of unique grays/colors. If you don't specify
- -maxval, pamstereogram uses the maxval of the input
--image. This option has no effect with -blackandwhite.
-+image. This option has no effect with -blackandwhite.
-
--- -patfile=pamfile
-+
- -patfile=pamfile
- - Specify an image to use as a repeated background pattern for
- the stereogram instead of a random-dot pattern. Intricate images
- generally produce a crisper 3-D effect that simpler images. The
-@@ -125,9 +128,9 @@ grayscale or color) as the pattern file. You cannot specify the
- -patfile option along with -blackandwhite,
- -grayscale, -color, or -maxval. The
- -verbose option will give you information on the ideal
--dimensions of the pattern file.
-+dimensions of the pattern file.
-
--
- -xbegin=pixels
-+
- -xbegin=pixels
- - Specify the horizontal coordinate at which to begin stereogram generation.
- The background pattern will be minimally distorted at this point and more
- distorted at greater distances. Consider using this in conjunction
-@@ -141,7 +144,7 @@ and pamstereogram actually ignores it with respect to -texfile
-
-
This option was new in Netpbm 10.71 (June 2015).
-
--
- -texfile=pamfile
-+
- -texfile=pamfile
- - Specify an image to use as the texture for a mapped-texture
- stereogram. The idea is that the depth-map image provides the depth
- values of the 3-D object/scene while the texture image provides the
-@@ -150,10 +153,10 @@ the depth-map image. (Note that it's required to have the same
- dimensions.) The texture image's background color is ignored when
- blending colors.
-
--
This option was new in Netpbm 10.53 (December 2010).
--
-+
This option was new in Netpbm 10.53 (December 2010).
-+
-
--- -bgcolor=color
-+
- -bgcolor=color
- - Use color as the texture image's background color instead
- of letting pamstereogram determine it automatically. Specify
- the color as described for the
-@@ -161,10 +164,10 @@ the color as described for the
- routine. The -bgcolor option is meaningful only in conjunction
- with -texfile.
-
--
This option was new in Netpbm 10.53 (December 2010).
--
-+
This option was new in Netpbm 10.53 (December 2010).
-+
-
--- -smoothing=pixels
-+
- -smoothing=pixels
- - When used without -texfile, attempt to eliminate artifacts
- introduced by edges in the depth map if pixels is greater than zero.
-
-@@ -175,29 +178,29 @@ by the stereogram's color constraints when producing a mapped-texture
- stereogram. In this case, the -smoothing option is helpful
- when the texture image includes smooth color transitions (as in a
- photograph) but makes crisp texture images (as in a line drawing)
--appear blurry.
-+appear blurry.
-
-
This option was new in Netpbm 10.53 (December 2010). Before
--Netpbm 10.61 (December 2012), it has no effect without -texfile.
-+Netpbm 10.61 (December 2012), it has no effect without -texfile.
-+
-
--
--- -xshift=pixels
-+
- -xshift=pixels
- - Shift the pattern image (designated by -patfile) to the
- right by pixels pixels (default: 0).
--
--This option is valid only along with -patfile.
-+
-+This option is valid only along with -patfile.
-
--- -yshift pixels
-+
- -yshift pixels
- - Shift the pattern image (designated by -patfile)
- downwards by pixels pixels (default: 0). This option is
--valid only along with -patfile.
-+valid only along with -patfile.
-
--- -magnifypat=scale
-+
- -magnifypat=scale
- - Magnify each pixel in the pattern file or each random dot by
- integral scaling factor scale. Note that
- pamstereogram applies the pattern magnification
- after pattern shifting (-xshift and
---yshift).
-+-yshift).
-
- - -guidebottom
-
-
-@@ -211,7 +214,7 @@ square. At that point, a crisp, 3-D image will appear.
-
This option was new in Netpbm 10.61 (December 2012). Before that,
- the presence of -guidesize, with a positive value, has the same
- effect.
--
-+
-
- - -guidetop
-
-
-@@ -221,7 +224,7 @@ Same as -guidebottom, except the guides go at the top of the image.
- the presence of -guidesize, with a negative value, has the same
- effect.
-
--
- -guidesize=pixels
-+
- -guidesize=pixels
-
- - The size (width and height) of each guide box.
-
-@@ -236,15 +239,15 @@ too, and if you specify it with a negative value, it behaves as if you
- specified -guidetop and specified guidesize with the absolute
- value of that negative value.
-
--
- -dpi=resolution
-+
- -dpi=resolution
- - Specify the resolution of the output device in dots per inch.
- The default is 100 DPI, which represents a fairly crisp screen
- resolution.
-
--
Before Netpbm 10.53 (December 2010), the default was 96 DPI.
--
-+
Before Netpbm 10.53 (December 2010), the default was 96 DPI.
-+
-
--- -crosseyed
-+
- -crosseyed
- - Invert the gray levels in the depth map (input image) so that the 3-D
- image pops out of the page where it would otherwise sink into the page and
- vice versa. Some people are unable to diverge their eyes and can only cross
-@@ -255,10 +258,10 @@ colors are farther from the eye.
-
-
Before Netpbm 10.53 (December 2010), pamstereogram used higher
- (lighter) numbers for things closer to the eye without
---crosseyed and vice versa.
-+-crosseyed and vice versa.
-+
-
--
--- -makemask
-+
- -makemask
- - Instead of a stereogram, output a PAM mask image showing
- coloring constraints. New pixels will be taken from the pattern
- file where the mask is black. Copies of existing pixels will be
-@@ -266,30 +269,30 @@ taken from the pattern file where the mask is white. The
- -makemask option can be used to help create more
- sophisticated pattern files (to use with -patfile) Note that
- -makemask ignores -magnifypat; it always produces
--masks that assume a pattern magnification of 1.
-+masks that assume a pattern magnification of 1.
-
--- -eyesep=inches
-+
- -eyesep=inches
- - Specify the separation in inches between your eyes. The
- default, 2.5 inches (6.4 cm), should be sufficient for most people
--and probably doesn't need to be changed.
-+and probably doesn't need to be changed.
-
--- -depth=fraction
-+
- -depth=fraction
- - Specify the output image's depth of field. That is,
- fraction represents the fractional distance of the near
- plane from the far plane. Smaller numbers make the 3-D image easier
- to perceive but flatter. Larger numbers make the 3-D image more
- difficult to perceive but deeper. The default, 0.3333, generally
--works fairly well.
-+works fairly well.
-
--- -planes=near_pixels,far_pixels
-+
- -planes=near_pixels,far_pixels
- - Explicitly specify the distance between repeated pixels in the near plane
- and in the far plane. This is an alternative to
- -eyesep and -depth. The following equalities hold:
-
-
-- - eyesep = 2 * far
-+
- eyesep = 2 * far
- - depth = 2 * (far − near) /
-- (2 * far − near)
-+ (2 * far − near)
-
-
- The number of distinct 3-D depths is far
-@@ -299,10 +302,10 @@ parameters (distance between eyes and tradeoff between perceptibility
- and depth) while -planes is a more computer-centric way (pixel
- distances in the resulting stereogram).
-
--
This option was new in Netpbm 10.59 (June 2012).
--
-+
This option was new in Netpbm 10.59 (June 2012).
-+
-
--- -randomseed=integer
-+
- -randomseed=integer
- - Specify a seed to be used for the random number generator.
- The default is to use a seed based on the time of day, to one second
- granularity.
-@@ -313,18 +316,19 @@ every time you run pamstereogram.
-
-
This is irrelevant if you use a pattern file (-patfile
- option), because there is no random element to pamstereogram's
--behavior.
-+behavior.
-
--This option was new in Netpbm 10.32 (February 2006).
-+
This option was new in Netpbm 10.32 (February 2006).
-+
-
--- -tileable
-+
- -tileable
-
- - Make the generated image horizontally tileable. This works by
- blending a left-to-right rendering (the equivalent
- of -xbegin=0) with a right-to-left rendering (the equivalent
- of -xbegin=width−1).
-
--
This option was new in Netpbm 10.91 (June 2020).
-+
This option was new in Netpbm 10.91 (June 2020).
-
-
-
-@@ -333,7 +337,7 @@ of -xbegin=width−1).
-
- The only parameter, infile, is the name of an input file
- that is a depth map image. If you don't specify infile, the
--input is from standard input.
-+input is from standard input.
-
- The input is a PAM image of depth 1. Each sample represents the
- distance from the eye that the 3-D image at that location should
-@@ -344,10 +348,10 @@ be. Lower (darker) numbers mean further from the eye.
-
-
- pamstereogram pays no attention to the image's tuple type and
--ignores all planes other than plane 0.
-+ignores all planes other than plane 0.
-
- Like any Netpbm program, pamstereogram will accept PNM
--input as if it were the PAM equivalent.
-+input as if it were the PAM equivalent.
-
- Mapped-texture Stereograms
-
-@@ -355,12 +359,12 @@ input as if it were the PAM equivalent.
- drawn with true colors. Unlike a SIRDS or tiled-image SIS, however,
- the image portrayed by an MTS is apparent in normal 2-D viewing. It
- appears repeated multiple times and overlapped with itself, but it is
--not hidden.
-+not hidden.
-
- You create an MTS with pamstereogram by passing the filename
- of a PAM "texture image" with a -texfile option. A
- texture image portrays the same 3-D object as the depth-map image but
--indicates the colors that the program should apply to the object.
-+indicates the colors that the program should apply to the object.
-
- pamstereogram ignores the texture image's background color when it
- overlaps copies of the 3-D object. This prevents, for example, a bright-red
-@@ -370,32 +374,32 @@ object remains bright red. A consequence of this feature is that an MTS looks
- best when the objects in the texture image have a crisp outline. Smooth
- transitions to the background color result in unwanted color artifacts around
- edges because the program ignores only exact matches with the
--background color.
-+background color.
-
- You should specify a larger-than-normal value for -eyesep
- (and/or -dpi) when producing an MTS. Otherwise, the 3-D object will
- repeat so many times that most colored pixels will overlap other colored
--pixels, reducing the number of true-colored pixels that remain.
-+pixels, reducing the number of true-colored pixels that remain.
-
- An MTS can employ a background pattern (-patfile). In this
- case, pamstereogram replaces background pixels with pattern pixels in
--the final step of generating the image.
-+the final step of generating the image.
-
-
- Miscellaneous
-
- A good initial test is to input an image consisting of a solid
- shape of distance 0 within a large field of maximum distance (e.g., a
--white square on a black background).
-+white square on a black background).
-
- With the default values for -dpi and -eyesep, pattern
--images that are 128 pixels wide can tile seamlessly.
-+images that are 128 pixels wide can tile seamlessly.
-
-
- EXAMPLES
-
- Generate a SIRDS out of small, brightly colored squares and
--prepare it for display on an 87 DPI monitor:
-+prepare it for display on an 87 DPI monitor:
-
-
- pamstereogram depthmap.pam \
-@@ -406,7 +410,7 @@ prepare it for display on an 87 DPI monitor:
- Generate a SIS by tiling a PPM file (a prior run with
- -verbose indicates how wide the pattern file should be for
- seamless tiling, although any width is acceptable for producing
--SISes):
-+SISes):
-
-
- pamstereogram depthmap.pam -patfile mypattern.ppm >3d.pam
-@@ -416,7 +420,7 @@ SISes):
- Generate an MTS by associating colors with a depth-mapped object
- (using a large eye separation to reduce the number of repetitions of
- the texture image) and twice smoothing over background-colored
--speckles:
-+speckles:
-
-
- pamstereogram depthmap.pam \
-@@ -427,21 +431,21 @@ speckles:
-
- SEE ALSO
-
-
-
-@@ -457,24 +461,25 @@ Netpbm 10.61 (December 2012).
-
-
- AUTHOR
--Copyright © 2006-2020 Scott Pakin, scott+pbm@pakin.org.
-+
Copyright © 2006-2020 Scott Pakin, scott+pbm@pakin.org.
-
- Table Of Contents
-
-