- -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 blank.
- 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 black 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.
Back to Contents
- 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 black.
- 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 black.
- 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.