convert(1) General Commands Manual convert(1)
NAME
convert - convert an image or sequence of images
SYNOPSIS
convert [ options ... ] input_file output_file
DESCRIPTION
Convert converts an input file using one image format to an output file with a differing image format. In addition, various types of image
processing can be performed on the converted image during the conversion process. Convert recognizes the image formats listed in ImageMag-
ick(1).
EXAMPLES
To make a thumbnail of a JPEG image, use:
convert -size 120x120 cockatoo.jpg -resize 120x120
+profile '*' thumbnail.jpg
In this example, "-size 120x120" gives a hint to the JPEG decoder that the image is going to be downscaled to 120x120, allowing it to run
faster by avoiding returning a full-resolution image. The "-resize 120x120" specifies the desired dimensions of the output image. It will
be scaled so its largest dimension is 120 pixels. The "+profile '*'" removes any ICM, EXIF, IPTC, or other profiles that might be present
in the input and aren't needed in the thumbnail.
To convert a MIFF image of a cockatoo to a SUN raster image, use:
convert cockatoo.miff sun:cockatoo.ras
To convert a multi-page PostScript document to individual FAX pages, use:
convert -monochrome document.ps fax:page
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
To convert a raw Gray image with a 128 byte header to a portable graymap, use:
convert -depth 8 -size 768x512+128 gray:raw
image.pgm
To convert a Photo CD image to a TIFF image, use:
convert -size 1536x1024 img0009.pcd image.tiff
convert img0009.pcd[4] image.tiff
To create a visual image directory of all your JPEG images, use:
convert 'vid:*.jpg' directory.miff
To annotate an image with blue text using font 12x24 at position (100,100), use:
convert -font helvetica -fill 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 with Mosaic(1), use:
convert -mattecolor "#697B8F" -frame 6x6 bird.jpg
icon.png
To create a MNG animation from a DNA molecule sequence, use:
convert -delay 20 dna.* dna.mng
OPTIONS
Options are processed in command line order. Any option you specify on the command line remains in effect for the set of images that fol-
lows, until the set is terminated by the appearance of any option or -noop. Some options only affect the decoding of images and others
only the encoding. The latter can appear after the final group of input images.
For a more detailed description of each option, see ImageMagick(1).
-adjoin
join images into a single multi-image file
-affine <matrix>
drawing transform matrix
-antialias
remove pixel aliasing
-append
append a set of images
-average
average a set of images
-background <color>
the background color
-blur <radius>x<sigma>
blur the image with a gaussian operator
-border <width>x<height>
surround the image with a border of color
-bordercolor <color>
the border color
-box <color>
set the color of the annotation bounding box
-cache <threshold>
megabytes of memory available to the pixel cache
-channel <type>
the type of channel
-charcoal <factor>
simulate a charcoal drawing
-chop <width>x<height>{+-}<x>{+-}<y>{%}
remove pixels from the interior of an image
-clip apply the clipping path, if one is present
-coalesce
merge a sequence of images
-colorize <value>
colorize the image with the pen color
-colors <value>
preferred number of colors in the image
-colorspace <value>
the type of colorspace
-comment <string>
annotate an image with a comment
-compose <operator>
the type of image composition
-compress <type>
the type of image compression
-contrast
enhance or reduce the image contrast
-crop <width>x<height>{+-}<x>{+-}<y>{%}
preferred size and location of the cropped image
-cycle <amount>
displace image colormap by amount
-debug enable debug printout
-deconstruct
break down an image sequence into constituent parts
-delay <1/100ths of a second>
display the next image after pausing
-density <width>x<height>
vertical and horizontal resolution in pixels of the image
-depth <value>
depth of the image
-despeckle
reduce the speckles within an image
-display <host:display[.screen]>
specifies the X server to contact
-dispose <method>
GIF disposal method
-dither
apply Floyd/Steinberg error diffusion to the image
-draw <string>
annotate an image with one or more graphic primitives
-edge <radius>
detect edges within an image
-emboss
emboss an image
-encoding <type>
specify the font encoding
-endian <type>
specify endianness (MSB or LSB) of output image
-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
-filter <type>
use this type of filter when resizing an image
-flatten
flatten a sequence of images
-flip create a "mirror image"
-flop create a "mirror image"
-font <name>
use this font when annotating the image with text
-frame <width>x<height>+<outer bevel width>+<inner bevel width>
surround the image with an ornamental border
-fuzz <distance>{%}
colors within this distance are considered equal
-gamma <value>
level of gamma correction
-gaussian <radius>x<sigma>
blur the image with a gaussian operator
-geometry <width>x<height>{+-}<x>{+-}<y>{%}{@} {!}{<}{>}
preferred size and location of the Image window.
-gravity <type>
direction primitive gravitates to when annotating the image.
-help print usage instructions
-implode <factor>
implode image pixels about the center
-intent <type>
use this type of rendering intent when managing the image color
-interlace <type>
the type of interlacing scheme
-label <name>
assign a label to an image
-level <value>
adjust the level of image contrast
-list <type>
the type of list
-loop <iterations>
add Netscape loop extension to your GIF animation
-map <filename>
choose a particular set of colors from this image
-mask <filename>
Specify a clipping mask
-matte store matte channel if the image has one
-median <radius>
apply a median filter to the image
-modulate <value>
vary the brightness, saturation, and hue of an image
-monochrome
transform the image to black and white
-morph <frames>
morphs an image sequence
-mosaic
create a mosaic from an image sequence
-negate
replace every pixel with its complementary color
-noise <radius|type>
add or reduce noise in an image
-noop NOOP (no option)
-normalize
transform image to span the full range of color values
-opaque <color>
change this color to the pen color within the image
-page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
size and location of an image canvas
-paint <radius>
simulate an oil painting
-pen <color>
specify the pen color for drawing operations
-ping efficiently determine image characteristics
-pointsize <value>
pointsize of the Postscript, OPTION1, or TrueType font
-preview <type>
image preview type
-process <command>
process a sequence of images
-profile <filename>
add ICM, IPTC, or generic profile to image
-quality <value>
JPEG/MIFF/PNG compression level
-raise <width>x<height>
lighten or darken image edges
-region <width>x<height>{+-}<x>{+-}<y>
apply options to a portion of the image
-resize <width>x<height>{%}{@}{!}{<}{>}
resize an image
-roll {+-}<x>{+-}<y>
roll an image vertically or horizontally
-rotate <degrees>{<}{>}
apply Paeth image rotation to the image
-sample <geometry>
scale image with pixel sampling
-sampling_factor <horizontal_factor>x<vertical_factor>
sampling factors used by JPEG or MPEG-2 encoder and YUV decoder/encoder.
-scale <geometry>
scale the image.
-scene <value>
set scene number
-seed <value>
pseudo-random number generator seed value
-segment <cluster threshold>x<smoothing threshold>
segment an image
-shade <azimuth>x<elevation>
shade the image using a distant light source
-sharpen <radius>x<sigma>
sharpen the image
-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
-size <width>x<height>{+offset}
width and height of the image
-solarize <factor>
negate all pixels above the threshold level
-spread <amount>
displace image pixels by a random amount
-stroke <color>
color to use when stroking a graphic primitive
-strokewidth <value>
set the stroke width
-swirl <degrees>
swirl image pixels about the center
-texture <filename>
name of texture to tile onto the image background
-threshold <value>
threshold the image
-tile <filename>
tile image when filling a graphic primitive
-transform
transform the image
-transparent <color>
make this color transparent within the image
-treedepth <value>
tree depth for the color reduction algorithm
-trim trim an image
-type <type>
the image type
-units <type>
the type of image resolution
-unsharp <radius>x<sigma>
sharpen the image with an unsharp mask operator
-use_pixmap
use the pixmap
-verbose
print detailed information about the image
-view <string>
FlashPix viewing parameters
-wave <amplitude>x<wavelength>
alter an image along a sine wave
-write <filename>
write an image sequence [convert, composite]
For a more detailed description of each option, see ImageMagick(1).
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:
Build a histogram, one for each color component of the image.
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.
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.
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: <bq>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.</bq>
ENVIRONMENT
DISPLAY
To get the default host, display number, and screen.
SEE ALSO
display(1), animate(1), identify(1), ImageMagick(1), montage(1), mogrify(1), composite(1)
COPYRIGHT
Copyright (C) 2002 ImageMagick Studio
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 mer-
chantability, 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 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 LLC 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.
AUTHORS
John Cristy, ImageMagick Studio LLC,
Glenn Randers-Pehrson, ImageMagick Studio LLC.
ImageMagick Date: 2002/02/15 01:00:00 convert(1)