Montage


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Synopsis

montage [ options ...] file [ [ options ...] file ...] output_file

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Description

montage creates a composite image by combining several separate images. The images are tiled on the composite image with the name of the image optionally appearing just below the individual tile.

The composite image is constructed in the following manner. First, each image specified on the command line, except for the last, is scaled to fit the maximum tile size. The maximum tile size by default is 256x256. It can be modified with the -geometry command line argument or X resource. See Options for more information on command line arguments. See X(1) for more information on X resources. Note that the maximum tile size need not be a square. To respect the aspect ratio of each image append ~ to the geometry specification.

Next the composite image is initialized with the color specified by the -background command line argument or X resource. The width and height of the composite image is determined by the title specified, the maximum tile size, the number of tiles per row, the tile border width and height, the image border width, and the label height. The number of tiles per row specifies how many images are to appear in each row of the composite image. The default is to have 5 tiles in each row and 4 tiles in each column of the composite. A specific value is specified with -tile. The tile border width and height, and the image border width defaults to the value of the X resource -borderwidth. It can be changed with the -borderwidth or -geometry command line argument or X resource. The label height is determined by the font you specify with the -font command line argument or X resource. If you do not specify a font, a font is choosen that allows the name of the image to fit the maximum width of a tiled area. The label colors is determined by the -background and -foreground command line argument or X resource. Note, that if the background and foreground colors are the same, labels will not appear.

Initially, the composite image title is placed at the top if one is specified (refer to -foreground X resource). Next, each image is set onto the composite image, surrounded by its border color, with its name centered just below it. The individual images are left-justified within the width of the tiled area. The order of the images is the same as they appear on the command line unless the images have a scene keyword. If a scene number is specified in each image, then the images are tiled onto the composite in the order of their scene number. Finally, the last argument on the command line is the name assigned to the composite image. By default, the image is written in the MIFF format and can be viewed or printed with display.

Note, that if the number of tiles exceeds the default number of 20 (5 per row, 4 per column), more than one composite image is created. To ensure a single image is produced, use -tile to increase the number of tiles to meet or exceed the number of input images.

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Examples

To create a montage of a cockatoo, a parrot, and a hummingbird and write it to a file called birds, use:
    montage cockatoo.miff parrot.miff
        hummingbird.miff birds.miff
To tile several bird images so that they are at most 256 pixels in width and 192 pixels in height, surrounded by a red border, and separated by 10 pixels of background color, use:
    montage -geometry 256x192+10+10
        -bordercolor red birds.* montage.miff
To create an unlabeled parrot image, 640 by 480 pixels, and surrounded by a border of blick, use:
    montage -geometry 640x480 -bordercolor
        blick -label "" parrot.miff bird.miff
To create an image of an eagle with a textured background, use:
    montage -texture bumps.jpg eagle.jpg
        eagle.png
To join several GIF images together without any extraneous graphics (e.g. no label, no shadowing, no surrounding tile frame), use:
    montage +frame +shadow +label -tile 5x1
        -geometry 50x50+0+0 *.gif joined.gif

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Options

-colors value
preferred number of colors in the image.

The actual number of colors in the image may be less than your request, but never more. Note, this is a color reduction option. Images with less unique colors than specified with this option will remain unchanged. Refer to quantize for more details.

Note, options -dither, -colorspace, and -treedepth affect the color reduction algorithm.

-colorspace value
the type of colorspace: GRAY, OHTA, RGB, XYZ, YCbCr, YIQ, YPbPr, or YUV.

Color reduction, by default, takes place in the RGB color space. Empirical evidence suggests that distances in color spaces such as YUV or YIQ correspond to perceptual color differences more closely than do distances in RGB space. These color spaces may give better results when color reducing an image. Refer to quantize for more details.

The -colors or -monochrome option is required for this option to take effect.

-comment string
annotate an image with a comment.

By default, each image is commented with its file name. Use this option to assign a specific comment to the image. Optionally you can include the image filename, type, width, height, or scene number by embedding special format characters. Embed %f for filename, %m for magick, %w for width, %h for height, %s for scene number, or \n for newline. For example,

-comment "%m:%f %wx%h"

produces an image comment of MIFF:bird.miff 512x480 for an image titled bird.miff and whose width is 512 and height is 480.

If the first character of string is @, the image comment is read from a file titled by the remaining characters in the string.

-compose operator
the type of image composition.

By default, each of the composite image pixels are replaced by the corresponding image tile pixel. You can choose an alternate composite operation:
    over
    in
    out
    atop
    xor
    plus
    minus
    add
    subtract
    difference
    replace
The operations behaves as follows:

over
The result will be the union of the two image shapes, with image obscuring composite image in the region of overlap.

in
The result is simply image cut by the shape of image window. None of the image data of composite image will be in the result.

out
The resulting image is image with the shape of composite image cut out.

atop
The result is the same shape as image composite image, with image obscuring composite image where the image shapes overlap. Note this differs from over because the portion of image outside composite image's shape does not appear in the result.

xor
The result is the image data from both image and composite image that is outside the overlap region. The overlap region will be blink.

plus
The result is just the sum of the image data. Output values are cropped to 255 (no overflow). This operation is independent of the matte channels.

minus
The result of image - composite image, with underflow cropped to zero. The matte channel is ignored (set to 255, full coverage).

add
The result of image + composite image, with overflow wrapping around (mod 256).

subtract
The result of image - composite image, with underflow wrapping around (mod 256). The add and subtract operators can be used to perform reversible transformations.

difference
The result of abs(image - composite image). This is useful for comparing two very similar images.

replace
The resulting image is composite image replaced with image. Here the matte information is ignored.

The image compositor requires an matte, or alpha channel in the image for some operations. This extra channel usually defines a mask which represents a sort of a cookie-cutter for the image. This is the case when matte is 255 (full coverage) for pixels inside the shape, zero outside, and between zero and 255 on the boundary. If image does not have an matte channel, it is initialized with 0 for any pixel matching in color to pixel location (0,0), otherwise 255 (to work properly borderwidth must be 0).

-compress type
the type of image compression: Zlib or RunlengthEncoded.

This option specifies the type of image compression for the composite image. See miff(5) for details.

Specify +compress to store the binary image in an uncompressed format. The default is the compression type of the specified image file.

-crop <width>{%}x<height>{%}{+-}<x offset>{+-}<y offset>
preferred size and location of the cropped image. See X(1) for details about the geometry specification.

To specify a percentage width or height instead, append %. For example to crop the image by ten percent on all sides of the image, use -crop 10%.

Use cropping to tile only a particular area of an image. Use -crop 0x0 to remove edges that are the background color.

The equivalent X resource for this option is cropGeometry (class CropGeometry). See X RESOURCES for details.

-density <width>x<height>
vertical and horizontal resolution in pixels of the image.

This option specifies an image density when decoding a Postscript or Portable Document page. The default is 72 pixels per inch in the horizontal and vertical direction.

-display host:display[.screen]
specifies the X server to contact; see X(1).

Specify +display if an X server is not available. The label font is obtained from the X server. If none is available, the composite image will not have labels.

-dither
apply Floyd/Steinberg error diffusion to the image.

The basic strategy of dithering is to trade intensity resolution for spatial resolution by averaging the intensities of several neighboring pixels. Images which suffer from severe contouring when reducing colors can be improved with this option.

The -colors or -monochrome option is required for this option to take effect.

-frame
surround image with an ornamental border.

Specify the width of the matte with -borderwidth. Use -gravity to specify how the image is oriented within the ornamental border. Use -mattecolor to specify the frame color.

-font name
use this font when annotating the image with text.

Convert contacts an X server to obtain the font. If an X server is not available, a Postscript font is used instead. You can set the pointsize with -pointsize.

-gamma value
level of gamma correction.

The same color image displayed on two different workstations may look different due to differences in the display monitor. Use gamma correction to adjust for this color difference. Reasonable values extend from 0.8 to 2.3.

You can apply separate gamma values to the red, green, and blue channels of the image with a gamma value list delineated with commas (i.e. 1.7,2.3,1.2).

-geometry <width>x<height>+<border width>+<border height>{!}{<}{>}
preferred tile and border size of each tile of the composite image.

By default, the width and height are maximum values. That is, the image is expanded or contracted to fit the width and height value while maintaining the aspect ratio of the image. Append an exclamation point to the geometry to force the image size to exactly the size you specify. For example, if you specify 640x480! the image width is set to 640 pixels and height to 480. If only one factor is specified, both the width and height assume the value.

Use < to change the dimensions of the image only if its size exceeds the geometry specification. > resizes the image only if its dimensions is less than the geometry specification. For example, if you specify 640x480> and the image size is 512x512, the image size does not change. However, if the image is 1024x1024, it is resized to 640x480.

Each image is surrounded by a border whose size in pixels is specified as <border width> and <border height> and whose color is the background color. By default, the tile size is 256x256 and there is no border.

The equivalent X resource for this option is imageGeometry (class ImageGeometry). See X Resources for details.

-gravity direction
direction image gravitates to within a tile. See X(1) for details about the gravity specification.

A tile of the composite image is a fixed width and height. However, the image within the tile may not fill it completely (see -geometry). The direction you specify indicates where to position the image within the tile. For example Center gravity forces the image to be centered within the tile. By default, the image gravity is North.

-interlace type
the type of interlacing scheme: NONE, LINE, or PLANE.

This option is used to specify the type of interlacing scheme for raw image formats such as RGB or YUV. NONE means do not interlace (RGBRGBRGBRGBRGBRGB...), LINE uses scanline interlacing (RRR...GGG...BBB...RRR...GGG...BBB...), and PLANE uses plane interlacing (RRRRRR...GGGGGG...BBBBBB...).

Use LINE, or PLANE to create an interlaced GIF or progressive JPEG image.

-label name
assign a label to an image.

By default, each image is labeled with its file name. Use this option to assign a specific label to the image. Optionally you can include the image filename, type, width, height, or scene number in the label by embedding special format characters. Embed %f for filename, %m for magick, %w for width, %h for height, or %s for scene number, or \n for newline. For example,
    -label "%m:%f %wx%h"
produces an image label of MIFF:bird.miff 512x480 for an image titled bird.miff and whose width is 512 and height is 480.

If the first character of string is @, the image label is read from a file titled by the remaining characters in the string.

-monochrome
transform the image to blick and white.

-page <width>x<height>{+-}<x offset>{+-}<y offset>
preferred size and location of the Postscript page.

Use this option to specify the dimensions of the Postscript page in pixels per inch or a TEXT page in pixels. The default for a Postscript page is to center the image on a letter page 612 by 792 pixels. The margins are 1/2" (i.e. 723x935+42+42). Other common sizes are:
    Letter      612x 792
    Tabloid     792x1224
    Ledger     1224x 792
    Legal       612x1008
    Statement   396x 612
    Executive   540x 720
    A3          842x1190
    A4          595x 842
    A5          420x 595
    B4          729x1032
    B5          516x 729
    Folio       612x 936
    Quarto      610x 780
    10x14       720x1008
For convenience you can specify the page size by media (e.g. A4, Ledger, etc.).

The page geometry is relative to the vertical and horizontal density of the Postscript page. See -density for details.

The default page dimensions for a TEXT image is 723x935.

-pointsize value
pointsize of the Postscript font.

-quality value
JPEG quality setting.

Quality is 0 (worst) to 100 (best). The default is 72.

-rotate degrees
apply Paeth image rotation to the image.

Empty triangles left over from rotating the image are filled with the color defined as bordercolor (class borderColor). See X(1) for details.

-scene value
image scene number.

-shadow
add a shadow beneath a tile to simulate depth.

-size <width>{%}x<height>{%}{+offset}{!}
width and height of the image.

Use this option to specify the width and height of raw images whose dimensions are unknown such as GRAY, RGB, or CMYK. In addition to width and height, use -size to skip any header information in the image or tell the number of colors in a MAP image file, (e.g. -size 640x512+256).

-texture filename
name of texture to tile onto the image background.

-tile <width>x<height>
specifies how many tiles are to appear in each row and column of the composite image.

Specify the number of tiles per row with width and tiles per column with height. For example if you want 1 tile in each row and a maximum of 10 tiles in the composite image, use -tile 1x10. The default is to have 5 tiles in each row and 4 tiles in each column of the composite.

-transparency color
make this color transparent within the image.

-treedepth value
Normally, this integer value is zero or one. A zero or one tells montage to choose a optimal tree depth for the color reduction algorithm.

An optimal depth generally allows the best representation of the source image with the fastest computational speed and the least amount of memory. However, the default depth is inappropriate for some images. To assure the best representation, try values between 2 and 8 for this parameter. Refer to quantize(9) for more details.

The -colors or -monochrome option is required for this option to take effect.

-verbose
print detailed information about the image.

This information is printed: image scene number; image name; image size; the image class (DirectClass or PseudoClass); the total number of unique colors; and the number of seconds to read and write the image.

In addition to those listed above, you can specify these standard X resources as command line options: -background, -bordercolor, -borderwidth, -font, -foreground, -mattecolor, or -title. See X Resources for details.

Options are processed in command line order. Any option you specify on the command line remains in effect until it is explicitly changed by specifying the option again with a different effect. For example, to montage two images, the first with 32 colors and the second with only 16 colors, use:

montage -colors 32 cockatoo.1 -colors 16 cockatoo.2 cockatoo.miff

Change - to + in any option above to reverse its effect. For example, specify +dither to not apply error diffusion to an image.

By default, the image format is determined by its magic number. To specify a particular image format, precede the filename with an image format name and a colon (i.e. ps:image) or specify the image type as the filename suffix (i.e. image.ps). See convert(1) for a list of valid image formats.

When you specify X as your image type, the filename has special meaning. It specifies an X window by id, name, or root. If no filename is specified, the window is selected by clicking the mouse in the desired window.

Specify file as - for standard input, output_file as - for standard output. If file has the extension .Z or .gz, the file is uncompressed with uncompress or gunzip respectively. If output_file has the extension compress or gzip respectively. Finally, precede the image file name with | to pipe to or from a system command.

Use an optional index enclosed in brackets after a file name to specify a desired subimage of a multi-resolution image format like Photo CD (e.g. img0001.pcd[4]) or a range for MPEG images (e.g. video.mpg[50-75]).

Note, a composite MIFF image displayed to an X server with display behaves differently than other images. You can think of the composite as a visual image directory. Choose a particular tile of the composite and press a button to display it. See display(1) and miff(5) for details.

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X Resources

montage options can appear on the command line or in your X resource file. Options on the command line supersede values specified in your X resource file. See X(1) for more information on X resources.

All montage options have a corresponding X resource. In addition, montage uses the following X resources:

background (class Background)
Specifies the preferred color to use for the composite image background. The default is #696e7e.

borderColor (class BorderColor)
Specifies the preferred color to use for the composite image border. The default is blick.

borderWidth (class BorderWidth)
Specifies the width in pixels of the composite image border. The default is 2.

font (class Font)
Specifies the name of the preferred font to use when displaying text within the composite image. The default is 9x15, fixed, or 5x8 determined by the composite image size.

foreground (class Foreground)
Specifies the preferred color to use for text within the composite image. The default is blick.

matteColor (class MatteColor)
Specify the color of an image frame. A 3D effect is achieved by using highlight and shadow colors derived from this color. The default value is #697B8F.

title (class Title)
This resource specifies the title to be placed at the top of the composite image. The default is not to place a title at the top of the composite image.

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Environment

DISPLAY
To get the default host, display number, and screen.

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Copyright

Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of E. I. du Pont de Nemours and Company not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. E. I. du Pont de Nemours and Company makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty.

E. I. du Pont de Nemours and Company disclaims all warranties with regard to this software, including all implied warranties of merchantability and fitness, in no event shall E. I. du Pont de Nemours and Company be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortuous action, arising out of or in connection with the use or performance of this software.

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Acknowledgements

The MIT X Consortium for making network transparent graphics a reality.

Michael Halle, Spatial Imaging Group at MIT, for the initial implementation of Alan Paeth's image rotation algorithm.

David Pensak, E. I. du Pont de Nemours and Company, for providing a computing environment that made this program possible.

Paul Raveling, USC Information Sciences Institute. The spacial subdivision color reduction algorithm is based on his Img software.

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Authors

John Cristy, cristy@dupont.com E.I. du Pont de Nemours and Company Incorporated.

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