mogrify(1)mogrify(1)NAMEmogrify - transform an image or sequence of images
SYNOPSISmogrify [ options ...] file [ [ options ...] file ...]
DESCRIPTIONmogrify transforms an image or a sequence of images.
These transforms include image scaling, image rotation,
color reduction, and others. The transmogrified image
overwrites the original image.
EXAMPLES
To convert all the TIFF files in a particular directory to
JPEG, use:
mogrify-format jpeg *.tiff
To scale an image of a cockatoo to exactly 640 pixels in
width and 480 pixels in height, use:
mogrify-geometry 640x480! cockatoo.miff
OPTIONS-antialias
remove pixel aliasing.
-background color
the background color.
-blur <radius>x<sigma>
blur the image with a Gaussian operator of the
given radius and standard deviation (sigma).
-border <width>x<height>
surround the image with a border of color. See
X(1) for details about the geometry specification.
-bordercolor color
the border color.
-box color
set the color of the annotation bounding box. See
-draw or for further details.
See X(1) for details about the color specification.
-cache threshold
megabytes of memory available to the pixel cache.
Image pixels are stored in memory until 80
megabytes of memory have been consumed. Subsequent
pixel operations are cached on disk. Operations to
memory are significantly faster but if your
ImageMagick $Date: 2001/12/04 18:54:24 $ 1
mogrify(1)mogrify(1)
computer does not have a sufficient amount of free
memory you may want to adjust this threshold value.
-channel type
the type of channel: Red, Green, Blue, Opacity,
Cyan, Yellow, Magenta, or lack.
Use this option to extract a particular channel
from the image. Matte, for example, is useful for
extracting the opacity values from an image.
-charcoal radius
simulate a charcoal drawing.
-colorize value
colorize the image with the fill color.
Specify the amount of colorization as a percentage.
You can apply separate colorization values to the
red, green, and blue channels of the image with a
colorization value list delineated with slashes
(e.g. 0/0/50).
-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
have any duplicate or unused colors removed. Refer
to quantize(5) for more details.
If more than one image is specified on the command
line, a single colormap is created and saved with
each image.
Note, options -colormap, -dither, -colorspace, and
-treedepth affect the color reduction algorithm.
-colorspace value
the type of colorspace: GRAY, OHTA, RGB,
Transparent, XYZ, YCbCr, YIQ, YPbPr, YUV, or CMYK.
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(5) for more
details.
The Transparent color space behaves uniquely in
ImageMagick $Date: 2001/12/04 18:54:24 $ 2
mogrify(1)mogrify(1)
that it preserves the matte channel of the image if
it exists.
The -colors or -monochrome option is required for
this option to take effect.
-comment string
annotate an image with a comment.
Use this option to assign a specific comment to the
image. You can include the image filename, type,
width, height, or other image attributes by
embedding special format characters:
%b file size
%c comment
%d directory
%e filename extention
%f filename
%h height
%i input filename
%k number of unique colors
%l label
%m magick
%n number of scenes
%o output filename
%p page number
%q quantum depth
%s scene number
%t top of filename
%u unique temporary filename
%w width
%x x resolution
%y y resolution
\n newline
\r carriage return
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.
-compress type
the type of image compression: None, BZip, Fax,
Group4, JPEG, LZW, RLE, or Zip.
Specify +compress to store the binary image in an
ImageMagick $Date: 2001/12/04 18:54:24 $ 3
mogrify(1)mogrify(1)
uncompressed format. The default is the
compression type of the specified image file.
-contrast
enhance or reduce the image contrast.
This option enhances the intensity differences
between the lighter and darker elements of the
image. Use -contrast to enhance the image or
+contrast to reduce the image contrast.
-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 apply image processing options, or
transmogrify, only a particular area of an image.
Omit the x and y offset to generate one or more
subimages of a uniform size.
Use cropping to crop a particular area of an image.
Use -crop 0x0 to trim edges that are the background
color. Add an x and y offset to leave a portion of
the trimmed edges with the image.
-cycle amount
displace image colormap by amount.
Amount defines the number of positions each
colormap entry is shifted.
-delay <1/100ths of a second>
display the next image after pausing.
This option is useful for regulating the animation
of a sequence of GIF images within Netscape.
1/100ths of a second must expire before the
redisplay of the image sequence. The default is no
delay between each showing of the image sequence.
The maximum delay is 65535.
You can specify a delay range (e.g. -delay 10-500)
which sets the minimum and maximum delay.
-density <width>x<height>
vertical and horizontal resolution in pixels of the
image.
ImageMagick $Date: 2001/12/04 18:54:24 $ 4
mogrify(1)mogrify(1)
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. This option is used in
concert with -page.
-depth value
depth of the image. This is the number of bits in
a pixel. The only acceptable values are 8 or 16.
-despeckle
reduce the speckles within an image.
-display host:display[.screen]
specifies the X server to contact; see X(1).
-dispose method
GIF disposal method.
Here are the valid methods:
0 No disposal specified.
1 Do not dispose between frames.
2 Overwrite frame with background color from header.
3 Overwrite with previous frame.
-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.
Use +dither to render Postscript without text or
graphic aliasing.
-draw string
annotate an image with one or more graphic
primitives.
Use this option to annotate an image with one or
more graphic primitives. The primitives include
point
line
rectangle
roundRectangle
arc
ImageMagick $Date: 2001/12/04 18:54:24 $ 5
mogrify(1)mogrify(1)
ellipse
circle
polyline
polygon
bezier
path
color
matte
text
image
Point, line, color, matte, text, and image each
require a single coordinate. Line requires a start
and end coordinate, while rectangle expects an
upper left and lower right coordinate. Circle has
a center coordinate and a coordinate on the outer
edge. Use Arc to circumscribe an arc within a
rectangle. Arcs require a start and end point as
well as the degree of rotation (e.g. 130,30 200,100
45,90). Use Ellipse to draw a partial ellipse
centered at the given point with the x-axis and y-
axis radius and start and end of arc in degrees
(e.g. 100,100 100,150 0,360). Finally, polyline
and polygon require three or more coordinates to
define its boundaries. Coordinates are integers
separated by an optional comma. For example, to
define a circle centered at 100,100 that extends to
150,150 use:
-draw 'circle 100,100 150,150'
Paths represent an outline of an object which is
defined in terms of moveto (set a new current
point), lineto (draw a straight line), curveto
(draw a curve using a cubic bezier), arc
(elliptical or circular arc) and closepath (close
the current shape by drawing a line to the last
moveto) elements. Compound paths (i.e., a path with
subpaths, each consisting of a single moveto
followed by one or more line or curve operations)
are possible to allow effects such as "donut holes"
in objects.
Use color to change the color of a pixel. Follow
the pixel coordinate with a method:
point
replace
floodfill
filltoborder
reset
Consider the target pixel as that specified by your
coordinate. The point method recolors the target
ImageMagick $Date: 2001/12/04 18:54:24 $ 6
mogrify(1)mogrify(1)
pixel. The replace method recolors any pixel that
matches the color of the target pixel. Floodfill
recolors any pixel that matches the color of the
target pixel and is a neighbor, whereas
filltoborder recolors any neighbor pixel that is
not the border color. Finally, reset recolors all
pixels.
Use matte to the change the pixel matte value to
transparent. Follow the pixel coordinate with a
method (see the color primitive for a description
of methods). The point method changes the matte
value of the target pixel. The replace method
changes the matte value of any pixel that matches
the color of the target pixel. Floodfill changes
the matte value of any pixel that matches the color
of the target pixel and is a neighbor, whereas
filltoborder changes the matte value of any
neighbor pixel that is not the border color
(-bordercolor). Finally reset changes the matte
value of all pixels.
Use text to annotate an image with text. Follow
the text coordinates with a string. If the string
has embedded spaces, enclose it in double quotes.
Optionally you can include the image filename,
type, width, height, or other image attributes by
embedding special format characters. See -comment
for details.
For example,
-draw 'text 100,100 "%m:%f %wx%h"'
annotates the image with MIFF:bird.miff 512x480 for
an image titled bird.miff and whose width is 512
and height is 480.
Use image to composite an image with another image.
Follow the image primitive with a composite
operator, image position, image size, and filename:
-draw 'image Over 100,100 225,225 image.jpg'
If the first character of string is @, the text is
read from a file titled by the remaining characters
in the string.
You can set the primitive color, font color, and
font bounding box color with -fill, -font, and -box
respectively. Options are processed in command
line order so be sure to use -fill before the -draw
option.
ImageMagick $Date: 2001/12/04 18:54:24 $ 7
mogrify(1)mogrify(1)-edge <radius>
enhance the edges of the image with a convolution
filter of the given radius.
-emboss <radius>x<sigma>
emboss the image with a convolution kernel of the
given radius and standard deviation (sigma).
-enhance
apply a digital filter to enhance a noisy image.
-equalize
perform histogram equalization to the image.
-fill color
color to use when filling a graphic primitive. See
-draw for further details.
-filter value
use this type of filter when resizing an image.
Use this option to affect the resizing operation of
an image (see -geometry). Choose from these
filters:
Point
Box
Triangle
Hermite
Hanning
Hamming
Blackman
Gaussian
Quadratic
Cubic
Catrom
Mitchell
Lanczos
Bessel
Sinc
The default filter is Lanczos.
-flip create a "mirror image" by reflecting the image
scanlines in the vertical direction.
-flop create a "mirror image" by reflecting the image
scanlines in the horizontal direction.
-format type
the image format type.
This option will convert any image to the image
ImageMagick $Date: 2001/12/04 18:54:24 $ 8
mogrify(1)mogrify(1)
format you specify. See convert(1) for a list of
image format types supported by ImageMagick.
By default the file is written to its original
name. However, if the filename extension matches a
supported format, the extension is replaced with
the image format type specified with -format. For
example, if you specify tiff as the format type and
the input image filename is image.gif, the output
image filename becomes image.tiff.
-font name
use this font when annotating the image with text.
If the font is a fully qualified X server font
name, the font is obtained from an X server (e.g.
-*-helvetica-medium-r-*-*-12-*-*-*-*-*-iso8859-*).
To use a TrueType font, precede the TrueType
filename with a @ (e.g. @times.ttf). Otherwise,
specify a Postscript, X11, or TrueType font (e.g.
helvetica).
-frame <width>x<height>+<outer bevel width>+<inner bevel
width>
surround the image with an ornamental border. See
X(1) for details about the geometry specification.
The color of the border is specified with the
-mattecolor command line option.
-fuzz distance
colors within this distance are considered equal.
A number of algorithms search for a target color.
By default the color must be exact. Use this
option to match colors that are close to the target
color in RGB space. For example, if you want to
automatically trim the edges of an image with -crop
0x0 but the image was scanned. The target
background color may differ by a small amount.
This option can account for these differences.
-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 slashes (i.e.
ImageMagick $Date: 2001/12/04 18:54:24 $ 9
mogrify(1)mogrify(1)
1.7/2.3/1.2).
Use +gamma to set the image gamma level without
actually adjusting the image pixels. This option
is useful if the image is of a known gamma but not
set as an image attribute (e.g. PNG images).
-gaussian <radius>x<sigma>
blur the image with a Gaussian operator of the
given width and standard deviation (sigma).
-geometry <width>x<height>{+-}<x offset>{+-}<y
offset>{%}{@}{!}{<}{>}
preferred width and height of the image. See X(1)
for details about the geometry specification.
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.
To specify a percentage width or height instead,
append %. The image size is multiplied by the
width and height percentages to obtain the final
image dimensions. To increase the size of an
image, use a value greater than 100 (e.g. 125%).
To decrease an image's size, use a percentage less
than 100.
Use @ to specify the maximum area in pixels of an
image.
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.
-gravity type
direction text gravitates to when annotating the
image: NorthWest, North, NorthEast, West, Center,
East, SouthWest, South, SouthEast. See X(1) for
details about the gravity specification.
The direction you choose specifies where to
ImageMagick $Date: 2001/12/04 18:54:24 $ 10
mogrify(1)mogrify(1)
position the text when annotating the image. For
example Center gravity forces the text to be
centered within the image. By default, the text
gravity is NorthWest.
-implode amount
implode image pixels about the center.
-interlace type
the type of interlacing scheme: None, Line, Plane,
or Partition. The default is None.
This option is used to specify the type of
interlacing scheme for raw image formats such as
RGB or YUV. No means do not interlace
(RGBRGBRGBRGBRGBRGB...), Line uses scanline
interlacing (RRR...GGG...BBB...RRR...GGG...BBB...),
and Plane uses plane interlacing
(RRRRRR...GGGGGG...BBBBBB...). Partition is like
plane except the different planes are saved to
individual files (e.g. image.R, image.G, and
image.B).
Use Line, or Plane to create an interlaced GIF or
progressive JPEG image. -label name assign a label
to an image.
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.
Optionally you can include the image filename,
type, width, height, or other image attributes by
embedding special format characters. See -comment
for details.
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.
When converting to Postscript, use this option to
specify a header string to print above the image.
Specify the label font with -font.
-level value
adjust the level of image contrast.
ImageMagick $Date: 2001/12/04 18:54:24 $ 11
mogrify(1)mogrify(1)
Give three point values delineated with slashes:
black, mid, and white (e.g. 10/1.0/65000). The
white and black points range from 0 to MaxRGB and
mid ranges from 0 to 10.
-list type
the type of list: Color, Delegate, Format, Magic,
Module, or Type.
This option lists entries from the ImageMagick
configuration files.
-loop iterations
add Netscape loop extension to your GIF animation.
A value other than zero forces the animation to
repeat itself up to iterations times.
-map filename
choose a particular set of colors from this image.
By default, color reduction chooses an optimal set
of colors that best represent the original image.
Alternatively, you can choose a particular set of
colors from an image file with this option. Use
+map to reduce all images in an image sequence to a
single optimal set of colors that best represent
all the images.
-matte store matte channel if the image has one otherwise
create an opaque one.
-median radius
apply a median filter to the image.
-modulate value
vary the brightness, saturation, and hue of an
image.
Specify the percent change in brightness, the color
saturation, and the hue separated by commas. For
example, to increase the color brightness by 20%
and decrease the color saturation by 10% and leave
the hue unchanged, use: -modulate 120,90.
-monochrome
transform the image to black and white.
-negate
replace every pixel with its complementary color
(white becomes black, yellow becomes blue, etc.).
The red, green, and blue intensities of an image
are negated. Use +negate to only negate the
ImageMagick $Date: 2001/12/04 18:54:24 $ 12
mogrify(1)mogrify(1)
grayscale pixels of the image.
-noise value
add or reduce noise in an image.
The principal function of noise peak elimination
filter is to smooth the objects within an image
without losing edge information and without
creating undesired structures. The central idea of
the algorithm is to replace a pixel with its next
neighbor in value within a pixel window, if this
pixel has been found to be noise. A pixel is
defined as noise if and only if this pixel is a
maximum or minimum within the pixel window. Use
radius to specify the width of the neighborhood.
Use +noise followed by a noise type to add noise to
an image. Choose from these noise types:
Uniform
Gaussian
Multiplicative
Impulse
Laplacian
Poisson
-normalize
transform image to span the full range of color
values.
This is a contrast enhancement technique.
-opaque color
change this color to the fill color within the
image. See -fill for more details.
-page <width>x<height>{+-}<x offset>{+-}<y
offset>{%}{!}{<}{>}
preferred size and location of an image canvas.
Use this option to specify the dimensions of the
Postscript page in dots per inch or a TEXT page in
pixels. The choices for a Postscript page are:
11x17 792 1224
Ledger 1224 792
Legal 612 1008
Letter 612 792
LetterSmall 612 792
ArchE 2592 3456
ArchD 1728 2592
ArchC 1296 1728
ArchB 864 1296
ArchA 648 864
ImageMagick $Date: 2001/12/04 18:54:24 $ 13
mogrify(1)mogrify(1)
A0 2380 3368
A1 1684 2380
A2 1190 1684
A3 842 1190
A4 595 842
A4Small 595 842
A5 421 595
A6 297 421
A7 210 297
A8 148 210
A9 105 148
A10 74 105
B0 2836 4008
B1 2004 2836
B2 1418 2004
B3 1002 1418
B4 709 1002
B5 501 709
C0 2600 3677
C1 1837 2600
C2 1298 1837
C3 918 1298
C4 649 918
C5 459 649
C6 323 459
Flsa 612 936
Flse 612 936
HalfLetter 396 612
For convenience you can specify the page size by
media (e.g. A4, Ledger, etc.). Otherwise, -page
behaves much like -geometry (e.g. -page
letter+43+43>).
To position a GIF image, use -page {+-}<x
offset>{+-}<y offset> (e.g. -page +100+200).
For a Postscript page, the image is sized as in
-geometry and positioned relative to the lower left
hand corner of the page by {+-}<x offset>{+-}<y
offset>. Use -page 612x792>, for example, to
center the image within the page. If the image
size exceeds the Postscript page, it is reduced to
fit the page.
The default page dimensions for a TEXT image is
612x792.
This option is used in concert with -density.
-paint radius
simulate an oil painting.
Each pixel is replaced by the most frequent color
ImageMagick $Date: 2001/12/04 18:54:24 $ 14
mogrify(1)mogrify(1)
in a circular neighborhood whose width is specified
with radius.
-pointsize value
pointsize of the Postscript, X11, or TrueType font.
-profile filename
add ICM color or IPTC newswire information profile
to image.
Use +profile icm or +profile iptc to remove the
respective profile.
-quality value
JPEG/MIFF/PNG compression level.
For the JPEG image format, quality is 0 (worst) to
100 (best). The default quality is 75.
Quality for the MIFF and PNG image format sets the
amount of image compression (quality / 10) and
filter-type (quality % 10). Compression quality
values range from 0 (worst) to 100 (best). If
filter-type is 4 or less, the specified filter-type
is used for all scanlines:
0: none
1: sub
2: up
3: average
4: Paeth
If filter-type is 5, adaptive filtering is used
when quality is greater than 50 and the image does
not have a color map, otherwise no filtering is
used.
If filter-type is 6 or more, adaptive filtering
with minimum-sum-of-absolute-values is used.
The default is quality is 75. Which means nearly
the best compression with adaptive filtering.
For further information, see the PNG specification
(RFC 2083), <http://www.w3.org/pub/WWW/TR>.
-raise <width>x<height>
lighten or darken image edges to create a 3-D
effect. See X(1) for details about the geometry
specification.
Use -raise to create a raised effect, otherwise use
+raise.
ImageMagick $Date: 2001/12/04 18:54:24 $ 15
mogrify(1)mogrify(1)-region <width>x<height>{+-}<x offset>{+-}<y offset>
apply options to a portion of the image.
By default, any command line options are applied to
the entire image. Use -region to restrict
operations to a particular area of the image.
-roll {+-}<x offset>{+-}<y offset>
roll an image vertically or horizontally. See X(1)
for details about the geometry specification.
A negative x offset rolls the image left-to-right.
A negative y offset rolls the image top-to-bottom.
-rotate degrees{<}{>}
apply Paeth image rotation to the image.
Use > to rotate the image only if its width exceeds
the height. < rotates the image only if its width
is less than the height. For example, if you
specify -90> and the image size is 480x640, the
image is not rotated by the specified angle.
However, if the image is 640x480, it is rotated by
-90 degrees.
Empty triangles left over from rotating the image
are filled with the color defined as background
(class backgroundColor).
-sample geometry
scale image with pixel sampling.
-scale geometry
scale image.
-scene value
image scene number.
-seed value
pseudo-random number generator seed value.
-segment <cluster threshold>x<smoothing threshold>
segment an image by analyzing the histograms of the
color components and identifying units that are
homogeneous with the fuzzy c-means technique.
Specify cluster threshold as the number of pixels
in each cluster must exceed the the cluster
threshold to be considered valid. Smoothing
threshold eliminates noise in the second derivative
of the histogram. As the value is increased, you
can expect a smoother second derivative. The
default is 1.5. See IMAGE SEGMENTATION for
details.
ImageMagick $Date: 2001/12/04 18:54:24 $ 16
mogrify(1)mogrify(1)-shade <azimuth>x<elevation>
shade the image using a distant light source.
Specify azimuth and elevation as the position of
the light source. Use +shade to return the shading
results as a grayscale image.
-sharpen <radius>x<sigma>
sharpen the image with a Laplacian operator of the
given radius and standard deviation (sigma).
-shave <width>x<height>
shave pixels from the image edges.
-shear <x degrees>x<y degrees>
shear the image along the X or Y axis by a positive
or negative shear angle.
Shearing slides one edge of an image along the X or
Y axis, creating a parallelogram. An X direction
shear slides an edge along the X axis, while a Y
direction shear slides an edge along the Y axis.
The amount of the shear is controlled by a shear
angle. For X direction shears, x degrees> is
measured relative to the Y axis, and similarly, for
Y direction shears y degrees is measured relative
to the X axis.
Empty triangles left over from shearing the image
are filled with the color defined as background
(class backgroundColor). See X(1) for details.
-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).
For Photo CD images, choose from these sizes:
192x128
384x256
768x512
1536x1024
3072x2048
Finally, use this option to choose a particular
resolution layer of a JBIG or JPEG image (e.g.
-size 1024x768).
ImageMagick $Date: 2001/12/04 18:54:24 $ 17
mogrify(1)mogrify(1)-solarize threshold
negate all pixels above the threshold level.
Specify factor as the percent threshold of the
intensity (0 - 99.9%).
This option produces a solarization effect seen
when exposing a photographic film to light during
the development process.
-spread amount
displace image pixels by a random amount.
Amount defines the size of the neighborhood around
each pixel to choose a candidate pixel to swap.
-stroke color
color to use when stroking a graphic primitive.
See -draw for further details.
-strokewidth value
set the stroke width. See -draw for further
details.
-swirl degrees
swirl image pixels about the center.
Degrees defines the tightness of the swirl.
-texture filename
name of texture to tile onto the image background.
-threshold value
threshold the image.
Create a bi-level image such that any pixel
intensity that is equal or exceeds the threshold is
reassigned the maximum intensity otherwise the
minimum intensity.
-tile filename
tile image when filling a graphic primitive.
-transparent color
make this color transparent within the image.
-treedepth value
Normally, this integer value is zero or one. A
zero or one tells mogrify 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
ImageMagick $Date: 2001/12/04 18:54:24 $ 18
mogrify(1)mogrify(1)
some images. To assure the best representation,
try values between 2 and 8 for this parameter.
Refer to quantize(5) for more details.
The -colors or -monochrome option is required for
this option to take effect.
-type type
set the image type: Bilevel, Grayscale, Palette,
PaletteMatte, TrueColor, TrueColorMatte,
ColorSeparation, ColorSeparationMatte, or Optimize.
-units type
the type of image resolution: Undefined,
PixelsPerInch, or PixelsPerCentimeter. The default
is Undefined.
-unsharp <radius>x<sigma>
sharpen the image with a unsharp mask operator of
the given radius and standard deviation (sigma).
-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 (if known); and the number of
seconds to read and transform the image. Refer to
miff(5) for a description of the image class.
If -colors is also specified, the total unique
colors in the image and color reduction error
values are printed. Refer to quantize(5) for a
description of these values.
-view string
FlashPix viewing parameters.
-wave <amplitude>x<wavelength>
alter an image along a sine wave.
Specify amplitude and wavelength to effect the
characteristics of the wave.
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 mogrify two images,
the first with 32 colors and the second with only 16
colors, use:
mogrify-colors 32 cockatoo.miff -colors 16
macaw.miff
ImageMagick $Date: 2001/12/04 18:54:24 $ 19
mogrify(1)mogrify(1)
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.
Specify file as - for standard input and output. If file
has the extension .Z or .gz, the file is uncompressed with
uncompress or gunzip respectively and subsequently
compressed using with compress or gzip. 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]). A subimage
specification can be disjoint (e.g. image.tiff[2,7,4]).
For raw images, specify a subimage with a geometry (e.g.
-size 640x512 image.rgb[320x256+50+50]).
Prepend an at sign (@) to a filename to read a list of
image filenames from that file. This is convenient in the
event you have too many image filenames to fit on the
command line.
IMAGE SEGMENTATION
Use -segment to segment an image by analyzing the
histograms of the color components and identifying units
that are homogeneous with the fuzzy c-means technique.
The scale-space filter analyzes the histograms of the
three color components of the image and identifies a set
of classes. The extents of each class is used to coarsely
segment the image with thresholding. The color associated
with each class is determined by the mean color of all
pixels within the extents of a particular class. Finally,
any unclassified pixels are assigned to the closest class
with the fuzzy c-means technique.
The fuzzy c-Means algorithm can be summarized as follows:
o Build a histogram, one for each color component
of the image.
o For each histogram, successively apply the scale-
space filter and build an interval tree of zero
crossings in the second derivative at each scale.
Analyze this scale-space ``fingerprint'' to
determine which peaks or valleys in the histogram
are most predominant.
o The fingerprint defines intervals on the axis of
the histogram. Each interval contains either a
ImageMagick $Date: 2001/12/04 18:54:24 $ 20
mogrify(1)mogrify(1)
minima or a maxima in the original signal. If each
color component lies within the maxima interval,
that pixel is considered ``classified'' and is
assigned an unique class number.
o Any pixel that fails to be classified in the
above thresholding pass is classified using the
fuzzy c-Means technique. It is assigned to one of
the classes discovered in the histogram analysis
phase.
The fuzzy c-Means technique attempts to cluster a pixel by
finding the local minima of the generalized within group
sum of squared error objective function. A pixel is
assigned to the closest class of which the fuzzy
membership has a maximum value.
For additional information see
Young Won Lim, Sang Uk Lee, "On The Color Image
Segmentation Algorithm Based on the Thresholding
and the Fuzzy c-Means Techniques", Pattern
Recognition, Volume 23, Number 9, pages 935-952,
1990.
SEE ALSOdisplay(1), animate(1), import(1), montage(1), convert(1),
composite(1)COPYRIGHT
Copyright (C) 2001 ImageMagick Studio, a non-profit
organization dedicated to making software imaging
solutions freely available.
Permission is hereby granted, free of charge, to any
person obtaining a copy of this software and associated
documentation files ("ImageMagick"), to deal in
ImageMagick without restriction, including without
limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of
ImageMagick, and to permit persons to whom the ImageMagick
is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice
shall be included in all copies or substantial portions of
ImageMagick.
The software is provided "as is", without warranty of any
kind, express or implied, including but not limited to the
warranties of merchantability, fitness for a particular
purpose and noninfringement. In no event shall
ImageMagick Studio be liable for any claim, damages or
other liability, whether in an action of contract, tort or
ImageMagick $Date: 2001/12/04 18:54:24 $ 21
mogrify(1)mogrify(1)
otherwise, arising from, out of or in connection with
ImageMagick or the use or other dealings in ImageMagick.
Except as contained in this notice, the name of the
ImageMagick Studio shall not be used in advertising or
otherwise to promote the sale, use or other dealings in
ImageMagick without prior written authorization from the
ImageMagick Studio.
ACKNOWLEDGEMENTS
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, for the
original idea of using space subdivision for the color
reduction algorithm.
AUTHORS
John Cristy, ImageMagick Studio
ImageMagick $Date: 2001/12/04 18:54:24 $ 22
