3ImageMagick Image Conversion Utility4NF,
B

 


Contents





Synopsis

J
convert [ options ... ] input_fileoutput_file


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Description

H
Convert converts an input file using one image format to anOoutput file with a differing image format. In addition, various types of imageHprocessing can be performed on the converted image during the conversion&process. Convert recognizes thefollowing image formats:



+
*AVS - AVS X image file.+
*KBIE+ - Joint Bi-level Image experts Group file interchange format.+
*4BMP+ - Microsoft Windows bitmap image file.+
*(CGM - Computer Graphics Metafile.+
*:CMYK - Raw cyan, magenta, yellow, and black bytes.+
*8DCX+ - ZSoft IBM PC multi-page Paintbrush file.+
*3DIB - Microsoft Windows bitmap image file.+
*2EPS - Adobe Encapsulated PostScript file.+
*<EPS2 - Adobe Level II Encapsulated PostScript file.+
*2EPSF - Adobe Encapsulated PostScript file.+
*@EPSI - Adobe Encapsulated PostScript Interchange format.+
*FAX+ - Group 3.+
*/FITS - Flexible Image Transport System.+
*CGIF - CompuServe graphics interchange format; 8-bit color.+
*QGIF87 - CompuServe graphics interchange format; 8-bit color (version 87a).+
*GRAY - Raw gray bytes.+
*KGRADATION - gradual passing from one shade to another. Specify theEdesired shading with the filename (e.g. gradation:red-blue).+
*"GRANITE - granite texture.+
*)HDF+ - Hierarchical Data Format.+
*HISTOGRAM+
*GHTML - Hypertext Markup Language a with client-side image map.+
*LJBIG+ - Joint Bi-level Image experts Group file interchange format.+
*VJPEG - Joint Photographic Experts Group JFIF format; compressed 24-bit color.+
*0MAP - colormap intensities and indices.+
*MATTE - Raw matte bytes.+
*)MIFF+ - Magick image file format.+
*KMONO - Bi-level bitmap in least-significant-byte (LSB) first order.+
*EMPEG+ - Motion Picture Experts Group file interchange format.+
* MTV+ -+
*+NETSCAPE - Netscape 216 color cube.+
*NULL - NULL image.+
*9PBM+ - Portable bitmap format (black and white).+
*PCD - Photo CD.+
*%PCL - Page Control Language.+
*,PCX - ZSoft IBM PC Paintbrush file.+
*)PDF+ - Portable Document Format.+
*5PGM+ - Portable graymap format (gray scale).+
*3PICT - Apple Macintosh QuickDraw/PICT file.+
*EPLASMA - plasma fractal image. Specify the base color as theMfilename (e.g. plasma:gray). Use fractal to initialize to.a random value (e.g. plasma:fractal).+
*)PNG - Portable Network Graphics.+
* PNM+ - Portable anymap.+
*/PPM+ - Portable pixmap format (color).+
*&PS+ - Adobe PostScript file.+
*/PS2+ - Adobe Level II PostScript file.+
*#RAD - Radiance image file.+
*.RGB - Raw red, green, and blue bytes.+
*5RGBA - Raw red, green, blue, and matte bytes.+
*5RLA - Alias/Wavefront image file; read only.+
*=RLE - Utah Run length encoded image file; read only.+
*$SGI+ - Irix RGB image file.+
*HSHTML - Hypertext Markup Language a with client-side image map.+
*SUN+ - SUN Rasterfile.+
*(TEXT - raw text file; read only.+
*,TGA+ - Truevision Targa image file.+
*)TIFF+ - Tagged Image File Format.+
*)TILE - tile image with a texture.+
*VICAR - read only.+
*&VID - Visual Image Directory.+
*0VIFF+ - Khoros Visualization image file.+
*1X - select image from X server screen.+
*IXC - constant image of X server color. Specify the image color*as the filename (e.g. xc:yellow).+
*=XBM - X Windows system bitmap, black and white only.+
*4XPM - X Windows system pixmap file (color).+
*9XWD - X Windows system window dump file (color).+
*#YUV - CCIR 601 4:1:1 file.


OSupport for some of these formats require additional programs or libraries.HREADME tells where to find this software.

NNote, a format delineated with + means that if more than one image is>specified, it is combined into a single multi-image file. UseB+adjoin if you want a single image produced for each frame.

LRaw images are expected to have one byte per pixel unless ImageMagickHis compiled in 16-bit mode. Here, the raw data is expected to be stored9two bytes per pixel in most-significant-byte-first order.



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Examples 

I
To convert a MIFF image of a cockatoo to a SUN raster image,use:

5
convert cockatoo.miff sun:cockatoo.ras

I

To convert a multi-page PostScript document to individualFAX pages, use:

7
convert -monochrome document.ps fax:page

I

To convert a TIFF image to a PostScript A4 page with the)image in the lower left-hand corner, use:

:
convert -page A4+0+0 image.tiff document.ps

D

To convert a raw Gray image with a 128 byte header to a portable graymap, use:

;
convert -size 768x512+128 gray:raw image.pgm

5

To convert a Photo CD image to a TIFF image, use:

=
convert -size 1536x1024 img0009.pcd image.tiff0
convert img0009.pcd[4] image.tiff

@

To create a visual image directory of all your JPEG images,use:

1
convert 'vid:*.jpg' directory.miff

@

To annotate an image with blue text using font 12x24 atposition (100,100), use:

^
convert -font 12x24 -pen blue -draw "text +100+100 Cockatoo" bird.jpg bird.miff

?

To tile a 640x480 image with a JPEG texture with bumps use:

=
convert -size 640x480 tile:bumps.jpg tiled.png

@

To surround an icon with an ornamental border to use withMosaic(1), use:

G
convert -mattecolor #697B8F -frame 6x6 bird.jpg icon.png

@

To create a GIF animation from a DNA molecule sequence, use:

.
convert -delay 20 dna.* dna.gif





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Options



-adjoin0
join images into a single multi-image file.



-average
average a set of images.



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

6

-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 borderColor).See X(1) for details.



-box colorC
set the color of the annotation bounding box. See -drawfor further details.

$

-charcoal factor
simulate a charcoal drawing.

=

See \fBX(1)\fP for details about the color specification.

#

-colorize value*
colorize the image with the pen color.

G

Specify the amount of colorization as a percentage. You can applyHseparate colorization values to the red, green, and blue channels of theKimage with a colorization value list delineated with slashes (e.g. 0/0/50).



-colors value,
preferred number of colors in the image.

8

The actual number of colors in the image may be less3than your request, but never more. Note, this is a0color reduction option. Images with less unique2colors than specified with this option will remain=unchanged. Refer to quantize for more details.

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

#

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

7

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 more4closely than do distances in RGB space. These color5spaces may give better results when color reducing anGimage. Refer to quantize for more details.

HThe 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 forthis option to take effect.

!

-comment string%
annotate an image with a comment.

5

By default, each image is commented with its file3name. Use this option to assign a specific comment3to the image. Optionally you can include the image1filename, type, width, height, or scene number by9embedding special format characters. Embed %f forJfilename, %m for magick, %w for width, %h for height,E%s for scene number, %b for file size in kilobytes, or$\n for newline. For example,



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


E

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

J

If the first character of string is @, the image comment9is read from a file titled by the remaining characters in the string.

-compress typeI
the type of image compression: Zip or RunlengthEncoded.

<

Specify +compress to store the binary image in an4uncompressed format. The default is the compression!type of the specified image file.



-contrast)
enhance or reduce the image contrast.

2

This option enhances the intensity differences5between the lighter and darker elements of the image.@Use -contrast to enhance the image or +contrast toreduce the image contrast.

?

-crop <width>{%}x<height>{%}{+-}<x%offset>{+-}<y offset> 5
preferred size and location of the cropped image..See X(1) for details about the geometryspecification.

4

To specify a percentage width or height instead,9append %. For example to crop the image by ten 8percent on all sides of the image, use -crop 10%.

9

Use cropping to apply image processing options to, orMdisplay, a particular area of an image. Use -crop 0x0 to remove edges8that are the background color. Omit the x and y offset4to generate one or more subimages of a uniform size.



-cycle amount'
displace image colormap by amount.

H

Amount defines the number of positions each colormap entry isshifted.

/

-delay <1/100ths of a second>)
display the next image after pausing.

5This option is useful for regulating the animation of=GIF images within Netscape.. 1/100ths of a second must0expire before the display of the next image. The?default is no delay between each showing of the image sequence.The maximum delay is 65535.

7

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

8

This option specifies an image density when decoding;a PostScript or Portable Document page. The default4is 72 pixels per inch in the horizontal and vertical direction.



-despeckle(
reduce the speckles within an image.

0

-display host:display[.screen]K
specifies the X server to contact. This option is used with convert for<obtaining image or font from this X server. see X(1).

!

-dispose method
GIF disposal method.

L

Graphics Interchange Format (GIF) Specification 89a of July 31, 1990 fordetails.



-dither7
apply Floyd/Steinberg error diffusion to the image.

9

The basic strategy of dithering is to trade intensity2resolution for spatial resolution by averaging the2intensities of several neighboring pixels. Images1which suffer from severe contouring when reducing(colors can be improved with this option.

C

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



-draw string:
annotate an image with one or more graphic primitives.

M

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


K

Point, line, color, matte, text, andFimage each require a single coordinate. Line requires aFstart and end coordinate, while rectangle expects an upper leftHand lower right coordinate. Circle has a center coordinate and aHcoordinate on the outer edge. Finally, polygon requires three orCmore coordinates defining its boundaries. Coordinates are integers@separated by an optional comma. For example, to define a circle0centered 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 thepixel coordinate with a method:
  point	  replace  floodfill  reset


H

Consider the target pixel as that specified by your coordinate. TheIpoint method recolors the target pixel. The replace method>recolors any pixel that matches the color of the target pixel.HFloodfill recolors any pixel that matches the color of the targetDpixel and is a neighbor. Finally, reset recolors all pixels.

H

Use matte to the change the pixel matte value to transparent.?Follow the pixel coordinate with a method (see the colorAprimitive for a description of methods). The point methodGchanges the matte value of the target pixel. The replace methodBchanges the matte value of any pixel that matches the color of theDtarget pixel. Floodfill changes the matte value of any pixelEthat matches the color of the target pixel and is a neighbor. Finally3reset changes the matte value of all pixels.

?

Use text to annotate an image with text. Follow theCtext coordinates with a string. If the string has embedded spaces,0enclose it in double quotes. Optionally you canCinclude the image filename, type, width, height, or scene number byCembedding special format characters. Embed %f for filename,J%m for magick, %w for width, %h for height, %sIfor scene number, %b for file size in kilobytes, or \n fornewline. For example,
'     -draw 'text 100,100 "%m:%f %wx%h"'


Eannotates the image with MIFF:bird.miff 512x480 for an imageCtitled bird.miff and whose width is 512 and height is 480.

FUse image to composite an image with another image. Follow the0image coordinates with the filename of an image.

K

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

MYou can set the primitive color, font color, and font bounding box color withE-pen, -font, and -box respectively. Options are=processed in command line order so be sure to use -pen(before the -draw option.



-edge factorG
detect edges within an image. Specify factor as the percentenhancement (0.0 - 99.9%). 



-enhance4
apply a digital filter to enhance a noisy image.



-equalize4
perform histogram equalization to the image.



-flipH
create a "mirror image" by reflecting the scanlines in the vertical direction.



-flop7
create a "mirror image" by reflecting the image&scanlines in the horizontal direction.



-font name6
use this font when annotating the image with text.

AConvert contacts an X server to obtain the font.LIf an X server is not available, a Postscript font is used instead. You can3set the pointsize with -pointsize.

P

-frame <width>x<height+<outer bevel width>+<inner bevel width>:
surround the image with an ornamental border. See9X(1) for details about the geometry specification.

5

The color of the border is specified with the'-mattecolor command line option.



-gamma value
level of gamma correction.

3

The same color image displayed on two different5workstations may look different due to differences in4the display monitor. Use gamma correction to adjust4for this color difference. Reasonable values extendfrom 0.8 to 2.3.

3

You can apply separate gamma values to the red,2green, and blue channels of the image with a gammaKvalue list delineated with slashes (i.e. 1.7,2.3,1.2).

M

-geometry <width>{%}x<height>{%}{!}{<}{>}:
preferred size and location of the Image window. See9X(1) for details about the geometry specification.5By default, the window size is the image size and the,location is chosen by you when it is mapped.

8

By default, the width and height are maximum values.3That is, the image is expanded or contracted to fit0the width and height value while maintaining the5aspect ratio of the image. Append an exclamation0point to the geometry to force the image size to7exactly the size you specify. For example, if you<specify 640x480! the image width is set to 640 pixels4and height to 480. If only one factor is specified,+both the width and height assume the value.

4

To specify a percentage width or height instead,4append %. The image size is multiplied by the width0and height percentages to obtain the final image4dimensions. To increase the size of an image, use a3value greater than 100 (e.g. 125%). To decrease an-image's size, use a percentage less than 100.

CUse > to change the dimensions of the image onlyDif its size exceeds the geometry specification. < resizesCthe image only if its dimensions is less than the geometryFspecification. For example, if you specify 640x480> and theCimage size is 512x512, the image size does not change. However, if1the image is 1024x1024, it is resized to 640x480.

CUse < to change the dimensions of the image onlyDif its size exceeds the geometry specification. > resizesCthe image only if its dimensions is less than the geometryFspecification. For example, if you specify 640x480> and theCimage size is 512x512, the image size does not change. However, if1the image is 1024x1024, it is resized to 640x480.

7There are 72 pixels per inch in PostScript coordinates.

!

-implode factorK
implode image pixels about the center. Specify factor as the8percent implosion (0 - 99.9%) or explosion (-99.9 - 0%).

!

-interlace typeK
the type of interlacing scheme: None, Line, Plane,2or Partition. The default is Plane.

I

This option is used to specify the type of interlacing scheme for rawIimage formats such as RGB or YUV. None means do notHinterlace (RGBRGBRGBRGBRGBRGB...), Line uses scanline interlacingC(RRR...GGG...BBB...RRR...GGG...BBB...), and Plane uses planeLinterlacing (RRRRRR...GGGGGG...BBBBBB...). Partition is like planeIexcept the different planes are saved to individual files (e.g. image.R,image.G, and image.B).

H

Use Line, or Plane to create an interlaced GIF !or progressive JPEG image.



-label name
assign a label to an image.

9

Use this option to assign a specific label to the5image. Optionally you can include the image file-5name, type, width, height, or scene number in the5label by embedding special format characters. EmbedP%f for filename, %m for magick, %w for width, %h forJheight, %s for scene number, %b for file size in kilobytes,(or \n for newline.. For example,



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

C

produces an image label of MIFF:bird.miff 512x480 for an?image titled bird.miff and whose width is 512 and heightis 480.

K

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

D

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

$

-linewidth value:
set the width of a line. See -draw for furtherdetails.

"

-loop iterations6
add Netscape loop extension to your GIF animation.

G

A value other than zero forces the animation to repeat itself up toiterations times.

!

-map filename6
choose a particular set of colors from this image.

E

By default, color reduction chooses an optimal set of colors thatCbest represent the original image. Alternatively, you can choose aBparticular set of colors from an image file with this option. UseI+map to reduce all images provided on the command line to a single9optimal set of colors that best represent all the images.



-matte-
store matte channel if the image has one.

!

-modulate value9
vary the brightness, saturation, and hue of an image.

7

Specify the percent change in brightness, the color,saturation, and the hue separated by commas.8For example, to increase the color brightness by 20% and2decrease 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.

8

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



-noise$
add or reduce noise in an image.

4

The principal function of noise peak elimination/filter is to smooth the objects within an image4without losing edge information and without creating.undesired structures. The central idea of the-algorithm is to replace a pixel with its next0neighbor in value within a 3 x 3 window, if this5pixel has been found to be noise. A pixel is defined2as noise if and only if this pixel is a maximum or minimum within the 3 x 3 window.

J

Use +noise followed by a noise type to add noise to an image.Choose from these noise types:
    uniform    gaussian    multiplicative    impulse
    laplacian    poisson




-normalize3
transform image to span the full range of colorvalues.

6

This is a contrast enhancement technique.

!

-opaque color4change this color to the pen color within the image.

%

See -pen for more details.



-pageD<width>x<height>{+-}<x offset>{+-}<y offset>4
size and location of the PostScript page.

4

Use this option to specify the dimensions of the;PostScript page in pixels per inch or a TEXT page in7pixels. The default for a PostScript page is to4center the image on a letter page 612 by 792 pixels.2The margins are 1/2" (i.e. 612x792+42+42). Othercommon 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.).

J

To place a Postscript image with a given size on a given location on aNpage, use -page +HOFFSET+VOFFSET -geometry WIDTHxHEIGHT (fill inHnumbers). Note: this is only for generating Postscript, not Encapsulated Postscript.

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

C

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

!

-paint radius
simulate an oil painting.

C

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



-pen colorL
set the color of the font or opaque color. See -draw for furtherdetails.

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

"

-pointsize value%
pointsize of the Postscript font.

-quality value
JPEG quality setting.

H

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

5

-raise <width>x<height>I
lighten or darken image edges to create a 3-D effect. See X(1)-for details about the geometry specification.

M

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.

O

By default, any command line options are applied to the entire image. UseH-region to restrict operations to a particular area of the image.

9

-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. A7negative y offset rolls the image top-to-bottom.

-

-rotate degrees{<}{>},
apply Paeth image rotation to the image.

O

Use > to rotate the image only if its width exceeds theNheight. < rotates the image only if its width is less thanLthe height. For example, if you specify -90> and the image sizeFis 480x640, the image is not rotated by the specified angle. However,6if the image is 640x480, it is rotated by -90 degrees.

9

Empty triangles left over from rotating the image are:filled with the color defined as bordercolor (class2borderColor). See X(1) for details.

"

-sample geometry>
scale image with pixel sampling. See -geometry for)details about the geometry specification.



-scene value
image scene number.

P

-segment <cluster threshold>x<smoothing threshold>L
segment an image by analyzing the histograms of the color components andHidentifying units that are homogeneous with the fuzzy c-means technique.

L

Specify cluster threshold as the number of pixels in each clusterKmust exceed the the cluster threshold to be considered valid. Smoothing>threshold eliminates noise in the second derivative of theGhistogram. As the value is increased, you can expect a smoother secondLderivative. The default is 1.5. See Image Segmentation for details.

:

-shade <azimuth>x<elevation>1
shade the image using a distant light source.

L

Specify azimuth and elevation as the position of the lightNsource. Use +shade to return the shading results as a grayscale image.image.

!

-sharpen factor;
sharpen an image. Specify factor as the percentenhancement (0.0 - 99.9%). 

5

-shear <x degrees>x<y degrees>7
shear the image along the X or Y axis by a positiveor negative shear angle. 

9

Shearing slides one edge of an image along the X or Y5axis, creating a parallelogram. An X direction shear4slides an edge along the X axis, while a Y direction5shear slides an edge along the Y axis. The amount of0the shear is controlled by a shear angle. For X:direction shears, x degrees is measured relative to6the Y axis, and similarly, for Y direction shears y/degrees is measured relative to the X axis.

9

Empty triangles left over from shearing the image are:filled with the color defined as bordercolor (class2borderColor). See X(1) for details.

<

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

6

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

1

For Photo CD images, choose from these sizes:

   192x128
   384x256
   768x512   1536x1024   3072x2048
N
Finally, use this option to choose a particular resolution layer of a JBIGimage (e.g. -size 1024x768).

"

-solarize factorL
negate all pixels above the threshold level. Specify factor6as the percent threshold of the intensity (0 - 99.9%).

J

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.

K

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.

6

Degrees defines the tightness of the swirl.

%

-transparency color1
make this color transparent within the image.

#

-texture filename6
name of texture to tile onto the image background.

"

-threshold value
threshold the image.

?

Create a bi-level image such that any pixel intensity thatOis equal or exceeds the threshold is reassigned the maximum intensity otherwisethe minimum intensity.

"

-treedepth value8
Normally, this integer value is zero or one. A zero3or one tells display to choose a optimal tree depth"for the color reduction algorithm.

.

An optimal depth generally allows the best3representation of the source image with the fastest3computational speed and the least amount of memory.4However, the default depth is inappropriate for some/images. To assure the best representation, try4values between 2 and 8 for this parameter. Refer to6quantize for more details.

C

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

.

-undercolor <undercolorAfactor>x<black-generationfactor>;
control undercolor removal and black generation on CMYKimages.

;

This option enables you to perform undercolor removal7and black generation on CMYK images-- images to be7printed on a four-color printing system. You can con-7trol how much cyan, magenta, and yellow to remove from7your image and how much black to add to it. The stan->dard undercolor removal is 1.0x1.0. You'll frequently7get better results, though, if the percentage of black7you add to your image is slightly higher than the per-7centage of C, M, and Y you remove from it. For exampleyou might try 0.5x0.7.



-verbose/
print detailed information about the image.

4

This information is printed: image scene number;<image name; image size; the image class (DirectClass;or PseudoClass); the total number of unique colors;3and the number of seconds to read and transform the?image. Refer to miff for a descriptionof the image class.

@

If -colors is also specified, the total unique colors1in the image and color reduction error values are=printed. Refer to quantize for adescription of these values.



A

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.

@

Change '-' to '+' in any option above to reverse its effect.CFor example, specify +matte to store the image without itsmatte channel.

@

By default, the image format is determined by its magic<number. To specify a particular image format, precede theCfilename with an image format name and a colon (i.e.Cps:image) or specify the image type as the filename suffix

B

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

8

Specify input_file as - for standard input,output_file as -Lfor standard output. If input_file has the extension .Z orC.gz, the file is uncompressed with uncompress or gunzipGrespectively. If output_file has the extension .Z or .gz,Jthe file size is compressed using with compress or gzip<respectively. Finally, precede the image file name with |$to pipe to or from a system command.

GUse an optional index enclosed in brackets after a file name to specifyCa desired subimage of a multi-resolution image format like Photo CDI(e.g. img0001.pcd[4]) or a range for MPEG images (e.g. video.mpg[50-75]).BA subimage specification can be disjoint (e.g. image.tiff[2,4,7]).GFor raw images, specify a subimage with a geometry (e.g. -size 640x512image.rgb[320x256+50+50]).

@

Single images are written with the filename you specify.<However, multi-part images (i.e. a multi-page PostScriptNdocument with +adjoin specified) are written with the filename followedOby a period (.) and the scene number. You can change this behavior byCembedding a printf format specification in the file name. For example,




image%02d.miff

/converts files image00.miff, image01.miff, etc.




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Image Segmentation

H
Use -segment to segment an image by analyzing the histogramsBof the color components and identifying units that are homogeneous9with 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 each0class is used to coarsely segment the image with6thresholding. The color associated with each class is5determined by the mean color of all pixels within the9extents of a particular class. Finally, any unclassifiedJpixels are assigned to the closest class with the fuzzy c-means technique.

9The fuzzy c-Means algorithm can be summarized as follows:





: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 to5the closest class of which the fuzzy membership has amaximum value.

For additional information see:

9Young Won Lim, Sang Uk Lee, "On The Color Image4Segmentation Algorithm Based on the Thresholding and7the Fuzzy c-Means Techniques", Pattern Recognition,)Volume 23, Number 9, pages 935-952, 1990.



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Environment



DISPLAY8
To get the default host, display number, and screen.



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Copyright

7
Copyright 1997 E. I. du Pont de Nemours and Company:Permission to use, copy, modify, distribute, and sell this8software and its documentation for any purpose is hereby6granted without fee, provided that the above copyright8notice appear in all copies and that both that copyright6notice and this permission notice appear in supporting4documentation, and that the name of E. I. du Pont de1Nemours and Company not be used in advertising or4publicity pertaining to distribution of the software:without specific, written prior permission. E. I. du Pont9de Nemours and Company makes no representations about the4suitability of this software for any purpose. It is5provided "as is" without express or implied warranty.

6

E. I. du Pont de Nemours and Company disclaims all6warranties with regard to this software, including all8implied warranties of merchantability and fitness, in no:event shall E. I. du Pont de Nemours and Company be liable9for any special, indirect or consequential damages or any6damages whatsoever resulting from loss of use, data or8profits, whether in an action of contract, negligence or6other tortious action, arising out of or in connection-with the use or performance of this software.


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Authors

>
John Cristy, G cristy@sympatico.org E.I. du Pont de Nemours and CompanyIncorporated.


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4[home page]IImage manipulation software that works like magic.