SYNOPSIS

stereograph [options] -b base [-t texture] [-o output]

DESCRIPTION

Stereograph is a stereogram generator. In detail it is a single image stereogram (SIS) generator. It produces twodimensional images that seem to be threedimensional.

base is the file describung the ''relief`` of the 3d model. It is a simple graphic where the brightness of a pixel defines its individual depth. The darker a pixel is, the more far away it will seem to be in the final stereogram - the brighter it is, the closer it will be.

The texture is that what everyone sees when regarding your stereogram - even if he cannot get in the third dimensions of the composition. If you use the -w swich this becomes optional.

The width of the texture stands for the maximum depth of any steregram and it cannot be greater than the distance of a viewer's two eyes - otherwise they won't be able to see anything in the stereogram but the beautiful great texture. As a hand rule, 100 should work nice for stereograms of 640*480 up to 800*600 pixels. Use 110 to 120 for greater ones.

The files given as base and texture must be supplied either in the tga or in the png format. Which you used is derived from the file name.

output is the file where the stereogram is written to. The file format to use is deduced from the filename given if not overridden by -f. (q.tga``, (q.png``, and (q.ppm`` are supported. If not given, stereograph will write the image in PPM or the format given with -f format to the standard output.

OPTIONS

-v

Be verbose.

-f outputformat

outputformat is one of the following: tga, png, or ppm.

-A

The Aid flag -A will add a pair of black triangles at the top of the stereogram to make it easier for unexperienced eyes to achieve the magic view.

Quality controling arguments

-a anti-aliasing

anti-aliasing describes a value between 1 and 32 (4 is the default) that declares how many pixels shall be calculated by the renderer virtually for ONE pixel.

You can calculate easily: physically you habe n depth levels, where n is the width of the texture used for the stereogram. With the AA feature you now have theoretically a*n levels. This feature increases _massively_ the color depth of the output file

-z zoom

based on the same idea as AA and has the same effects but physically increases the file size. Values range from 1 (default) up to 32.

perspective

-d distance

distance describes the distance of your eyes and the virtual glass that is between you and your stereogram. Allowed are values from 0.0 up to 20.0 where 5.0 is the default.

-p front factor

front factor defines the finally used depth space; value between 0.0 and 1.0.

-e eye-shift

eye-shift (a value between -1.0 and 1.0) controls the perspective along the x axis (left to right). That is if e is positive the image is shifted slightly to the right. The default value of 0.0 is exactly the centered perspective.

layout

-x texture-insert-x

texture-insert-x is a value between 0 and the width of the texture controlling where the texture is inserted the first time and where the rendering process begins its round. default: 0 (left image border).

-y texture-insert-y

texture-insert-y is a value between 0 and the height of the texture controlling where the texture is inserted the first time and where the rendering process begins its round. default: 0 (top image border).

-w texture-width

texture-width specifies the texture width to use for the stereogram. This option tells stereograph to generate a random texture or if a texture was defined it resizes the texture to match your dimension. Note that this can only reduce the width and stereograph doesn't care about image ratios. It just cuts your texture. Random textures cannot be used with transparent rendering.

-M, -G, -C, -S

Use one of there flags to define which color type the random texture should conform to. Use -M for monochrome, -G for a grayscale or -C for a random color texture. Please note that the random texture feature cannot be combined with transparent rendering and that anti-aliasing increases the color depth of you image - even if you use a monochrome texture. To disable anti-aliasing use -a 1.

The -S flag is experimental - it generates an artistic random texture.

base options

-I

inverts a base (non-transparent rendering only)

-L

disables linear rendering.

-R

The anti-artefacts feature tells stereograph to process every second line in reversed order to prevent artefacts. This flag should be used only with random textures.

transparancy

Transparent stereograms are rendered in the same way as normal stereograms, the only difference for you is to define more than one input base file and provide respectively the same number of textures. The different bases must have the same dimensions, the textures must equal themselves in the width. You may use the -w option to let steregraph resize them interactively for you.

-l (none|back|top)

adjusts the base levels for transparent rendering: the keyword none keeps the defined height levels of the base images, back adjusts the bottom area of all upper layers to the level defined by the preceding layer and top adjusts the areas of upper layers that are not as far as the preceeding layer to the level of the preceding layer.

AUTHOR

stereograph has been written by Fabian Januszewski <[email protected]>.

This manual page was written by Peter Palfrader <[email protected]> using large parts from the README file, for the Debian GNU/Linux system (but may be used by others).

COMMENT

This manpage documents version 0.30a of stereograph.