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mogrify(1)					     mogrify(1)

NAME
       mogrify - transform an image or sequence of images

SYNOPSIS
       mogrify [ options ...] file [ [ options ...] file ...]

DESCRIPTION
       mogrify 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
       -blur factor
	      blurs an image.  Specify factor as the percent
	      enhancement (0.0 - 99.9%).

       -border <width>x<height>
	      surround the image with a border of color.  See
	      X(1) for details about the geometry specification.

	      The color of the border is obtained from the X
	      server and is defined as bordercolor (class border-
	      Color).  See X(1) for details.

       -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.

       -charcoal factor
	      simulate a charcoal drawing.

       -colorize value
	      colorize the image with the pen 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).

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       -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(9) 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, Transpar-
	      ent, XYZ, YCbCr, YIQ, YPbPr, or YUV.

	      Color reduction, by default, takes place in the RGB
	      color space.  Empirical evidence suggests that dis-
	      tances in color spaces such as YUV or YIQ corre-
	      spond 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(9) for more details.

	      The Transparent color space behaves uniquely in
	      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.

	      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, %d for directory, %e for filename exten-
	      tion, %t for top of filename, %m for magick, %w for
	      width, %h for height, %s for scene number, %b for
	      file size, 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.

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	      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: No, RunlengthEn-
	      coded, or Zip.

	      Specify +compress to store the binary image in an
	      uncompressed format.  The default is the compres-
	      sion 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 +con-
	      trast 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 specifica-
	      tion.

	      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.
	      Use -crop 0x0 to remove edges that are the back-
	      ground color.   Omit the x and y offset to generate
	      one or more subimages of a uniform size.

       -cycle amount
	      displace image colormap by amount.

	      Amount defines the number of positions each col-
	      ormap 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 redis-
	      play of the image sequence.  The default is no
	      delay between each showing of the image sequence.
	      The maximum delay is 65535.

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

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

       -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.
		   2	Restore to background color.
		   3	Restore to previous.

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

	      The basic strategy of dithering is to trade inten-
	      sity 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.

       -draw string
	      annotate an image with one or more graphic primi-
	      tives.

	      Use this option to annotate an image with one or
	      more graphic primitives.	The primitives include

		   point
		   line
		   rectangle
		   fillRectangle
		   circle
		   fillCircle
		   polygon
		   fillPolygon
		   color
		   matte
		   text
		   image

	      Point, line, color, matte, text, and image each

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	      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.  Finally, polygon requires three or more
	      coordinates defining 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'

	      Use color to change the color of a pixel. Follow
	      the pixel coordinate with a method:

		   point
		   replace
		   floodfill
		   reset

	      Consider the target pixel as that specified by your
	      coordinate.  The point method recolors the target
	      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.  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. 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 scene number by embedding
	      special format characters.  Embed %f for filename,
	      %d for directory, %e for filename extention, %t for
	      top of filename, %m for magick, %w for width, %h
	      for height, %s for scene number, or \n for newline.
	      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

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	      and height is 480.

	      If the first character of the string is @, the text
	      is read from a file titled by the remaining charac-
	      ters in the string.

	      Use image to composite an image with another image.
	      Follow the image coordinates with the filename of
	      an image.

	      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 -pen, -font, and -box
	      respectively.  Options are processed in command
	      line order so be sure to use -pen before the -draw
	      option.

       -edge factor
	      detect edges with an image.  Specify factor as the
	      percent enhancement (0.0 - 99.9%).

       -emboss
	      emboss the image.

       -enhance
	      apply a digital filter to enhance a noisy image.

       -equalize
	      perform histogram equalization to the image.

       -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
	      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.

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

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

       -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 -mat-
	      tecolor command line option.

       -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 val-
	      ues 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.
	      1.7/2.3/1.2).

       -geometry <width>{%}x<height>{%}{!}{<}{>}
	      preferred width and height of the image.	See X(1)
	      for details about the geometry specification.

	      By default, the width and height are maximum val-
	      ues.  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 exclama-
	      tion 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 change the dimensions of the image only if

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	      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.

       -implode factor
	      implode image pixels about the center. Specify fac-
	      tor as the percent implosion (0 - 99.9 %) or explo-
	      sion (-99.9 - 0)

       -interlace type
	      the type of interlacing scheme: No, Line, Plane, or
	      Partition.  The default is Plane.

	      This option is used to specify the type of inter-
	      lacing scheme for raw image formats such as RGB or
	      YUV.  No means do not interlace (RGBRGBRGBRGBRG-
	      BRGB...), 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 file-
	      name, type, width, height, or scene number in the
	      label by embedding special format characters.
	      Embed %f for filename, %d for directory, %e for
	      filename extention, %t for top of 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.

	      When converting to Postscript, use this option to
	      specify a header string to print above the image.

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       -linewidth value
	      set the width of a line.	See -draw for further
	      details.

       -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.

       -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 20/-10.

       -monochrome
	      transform the image to black and white.

       -negate
	      apply color inversion to image.

	      The red, green, and blue intensities of an image
	      are negated.    Use +negate to only negate the
	      grayscale pixels of the image.

       -noise 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 creat-
	      ing undesired structures. The central idea of the
	      algorithm is to replace a pixel with its next
	      neighbor in value within a 3 x 3 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 3 x 3 window.  PP Use
	      +noise followed by a noise type to add noise to an
	      image.  Choose from these noise types:

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		  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 pen color within the
	      image.  See -pen for more details.

       -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 pix-
	      els. The margins are 1/2" (i.e.  612x792+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.).

	      To place a Postscript image with a given size on a
	      given location on a page, use -page +HOFFSET+VOFF-
	      SET -geometry WIDTHxHEIGHT (fill in numbers). Note:
	      this is only for generating Postscript, not Encap-
	      sulated Postscript.

	      To position a GIF image, use -page +LEFT+TOP (e.g.
	      -page +100+200).

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	      The default page dimensions for a TEXT image is
	      612x792.

       -paint radius
	      simulate an oil painting.

	      Each pixel is replaced by the most frequent color
	      in a circular neighborhood whose width is specified
	      with radius.

       -pen color
	      set the color of the font or opaque color.  See
	      -draw for further details.

	      See X(1) for details about the color specification.

       -pointsize value
	      pointsize of the Postscript font.

       -quality value
	      JPEG quality setting.

	      Quality is 0 (worst) to 100 (best). The default is
	      75.

       -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.

       -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 opera-
	      tions 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 spec-
	      ify -90> and the image size is 480x640, the image

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	      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 bordercolor
	      (class borderColor).

       -sample geometry
	      scale image with pixel sampling.

       -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 thresh-
	      old 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.

       -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 factor
	      sharpen an image. Specify factor as the percent
	      enhancement (0.0 - 99.9%).

       -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 mea-
	      sured relative to the Y axis, and similarly, for Y
	      direction shears y degrees is measured relative to
	      the X axis.

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	      Empty triangles left over from shearing the image
	      are filled with the color defined as bordercolor
	      (class borderColor).  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).

       -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.

       -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 inten-
	      sity that is equal or exceeds the threshold is

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	      reassigned the maximum intensity otherwise the min-
	      imum intensity.

       -transparency 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 repre-
	      sentation of the source image with the fastest com-
	      putational 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.

       -undercolor <undercolor factor>x<black-generation factor>
	      control undercolor removal and black generation on
	      CMYK images.

	      This option enables you to perform undercolor
	      removal and black generation on CMYK images--
	      images to be printed on a four-color printing sys-
	      tem. You can control how much cyan, magenta, and
	      yellow to remove from your image and how much black
	      to add to it.  The standard undercolor removal is
	      1.0x1.0.	You'll frequently get better results,
	      though, if the percentage of black you add to your
	      image is slightly higher than the percentage of C,
	      M, and Y you remove from it.  For example you might
	      try 0.5x0.7.

       -verbose
	      print detailed information about the image.

	      This information is printed: image scene number;
	      image name;  image size; the image class (Direct-
	      Class 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 col-
	      ors in the image and color reduction error values
	      are printed.  Refer to quantize(9) for a descrip-
	      tion of these values.

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mogrify(1)					     mogrify(1)

       -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 col-
       ors, use:

	    mogrify -colors 32 cockatoo.miff -colors 16
       macaw.miff

       Change - to + in any option above to reverse its effect.
       For example, specify +compress to store the binary image
       in an uncompressed format.

       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 com-
       pressed using with compress or gzip.  Finally, precede the
       image file name with | to pipe to or from a system com-
       mand.

       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]).

IMAGE SEGMENTATION
       Use -segment to segment an image by analyzing the his-
       tograms 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.

ImageMagick		 1 May 1994			 15

mogrify(1)					     mogrify(1)

       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 deter-
	      mine 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
	      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 member-
       ship 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 Recogni-
	      tion, Volume 23, Number 9, pages 935-952, 1990.

SEE ALSO
       display(1), animate(1), import(1), montage(1), convert(1),
       combine(1), xtp(1)

COPYRIGHT
       Copyright 1997 E. I. du Pont de Nemours and Company

       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 public-
       ity pertaining to distribution of the software without
       specific, written prior permission.  E. I. du Pont de

ImageMagick		 1 May 1994			 16

mogrify(1)					     mogrify(1)

       Nemours and Company makes no representations about the
       suitability of this software for any purpose.  It is pro-
       vided "as is" without express or implied warranty.

       E. I. du Pont de Nemours and Company disclaims all war-
       ranties 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 tortious action, arising out of or in connection
       with the use or performance of this software.

ACKNOWLEDGEMENTS
       Michael Halle, Spatial Imaging Group at MIT, for the ini-
       tial implementation of Alan Paeth's image rotation algo-
       rithm.

       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, E.I. du Pont de Nemours and Company Incorpo-
       rated

ImageMagick		 1 May 1994			 17

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