「convert」

  LINUX MANUAL PAGES

convert – convert between image formats as well as resize an image, blur, crop, despeckle, dither, draw on, flip, join, re-sample, and much more.

SYNOPSIS

convert [input-option] input-file [output-option] output-file

OVERVIEW

The convert program is a member of the ImageMagick(1) suite of tools. Use it to convert between image for‐
mats as well as resize an image, blur, crop, despeckle, dither, draw on, flip, join, re-sample, and much
more.

For more information about the convert command, point your browser to file:///usr/share/doc/imagemag
ick-6-common/html/www/convert.html (on debian system you may install the imagemagick-6-doc package) or
http://www.imagemagick.org/script/convert.php.

DESCRIPTION

Image Settings

-adjoin join images into a single multi-image file
-affine matrix affine transform matrix
-alpha option activate, deactivate, reset, or set the alpha channel
-antialias remove pixel-aliasing
-authenticate value decrypt image with this password
-attenuate value lessen (or intensify) when adding noise to an image
-background color background color
-bias value add bias when convolving an image
-black-point-compensation

use black point compensation

-blue-primary point chromaticity blue primary point

-bordercolor color border color

-caption string assign a caption to an image

-cdl filename color correct with a color decision list

-channel type apply option to select image channels

-clip clip along the first path from the 8BIM profile

-clip-mask filename associate a clip mask with the image

-clip-path id clip along a named path from the 8BIM profile

-colors value preferred number of colors in the image

-colorspace type alternate image colorspace

-comment string annotate image with comment

-compose operator set image composite operator

-compress type type of pixel compression when writing the image

-decipher filename convert cipher pixels to plain pixels

-define format:option

define one or more image format options

-delay value display the next image after pausing

-density geometry horizontal and vertical density of the image

-depth value image depth

-direction type render text right-to-left or left-to-right

-display server get image or font from this X server

-dispose method layer disposal method

-dither method apply error diffusion to image

-encipher filename convert plain pixels to cipher pixels

-encoding type text encoding type

-endian type endianness (MSB or LSB) of the image

-family name render text with this font family

-features distance analyze image features (e.g. contrast, correlation)

-fill color color to use when filling a graphic primitive

-filter type use this filter when resizing an image

-flatten flatten a sequence of images

-font name render text with this font

-format “string” output formatted image characteristics

-fuzz distance colors within this distance are considered equal

-gravity type horizontal and vertical text placement

-green-primary point chromaticity green primary point

-intensity method method to generate intensity value from pixel

-intent type type of rendering intent when managing the image color

-interlace type type of image interlacing scheme

-interline-spacing value

set the space between two text lines

-interpolate method pixel color interpolation method

-interword-spacing value

set the space between two words

-kerning value set the space between two letters

-label string assign a label to an image

-limit type value pixel cache resource limit

-loop iterations add Netscape loop extension to your GIF animation

-mask filename associate a mask with the image

-matte store matte channel if the image has one

-mattecolor color frame color

-metric type measure differences between images with this metric

-moments report image moments

-monitor monitor progress

-orient type image orientation

-page geometry size and location of an image canvas (setting)

-ping efficiently determine image attributes

-pointsize value font point size

-precision value maximum number of significant digits to print

-preview type image preview type

-quality value JPEG/MIFF/PNG compression level

-quiet suppress all warning messages

-red-primary point chromaticity red primary point

-regard-warnings pay attention to warning messages

-remap filename transform image colors to match this set of colors

-respect-parentheses settings remain in effect until parenthesis boundary

-sampling-factor geometry

horizontal and vertical sampling factor

-scene value image scene number

-seed value seed a new sequence of pseudo-random numbers

-size geometry width and height of image

-statistic type geometry

replace each pixel with corresponding statistic from the neighborhood

-stretch type render text with this font stretch

-stroke color graphic primitive stroke color

-strokewidth value graphic primitive stroke width

-style type render text with this font style

-support factor resize support: > 1.0 is blurry, < 1.0 is sharp

-synchronize synchronize image to storage device

-taint declare the image as modified

-texture filename name of texture to tile onto the image background

-tile-offset geometry

tile offset

-treedepth value color tree depth

-transparent-color color

transparent color

-undercolor color annotation bounding box color

-units type the units of image resolution

-verbose print detailed information about the image

-view FlashPix viewing transforms

-virtual-pixel method

virtual pixel access method

-weight type render text with this font weight

-white-point point chromaticity white point

Image Operators

-adaptive-blur geometry

adaptively blur pixels; decrease effect near edges

-adaptive-resize geometry

adaptively resize image with data dependent triangulation

-adaptive-sharpen geometry

adaptively sharpen pixels; increase effect near edges

-annotate geometry text

annotate the image with text

-auto-gamma automagically adjust gamma level of image

-auto-level automagically adjust color levels of image

-auto-orient automatically orient image

-bench iterations measure performance

-black-threshold value

force all pixels below the threshold into black

-blue-shift factor simulate a scene at nighttime in the moonlight

-blur geometry reduce image noise and reduce detail levels

-border geometry surround image with a border of color

-brightness-contrast geometry

improve brightness / contrast of the image

-canny geometry detect edges in the image

-charcoal radius simulate a charcoal drawing

-chop geometry remove pixels from the image interior

-clamp keep pixel values in range (0-QuantumRange)

-clip clip along the first path from the 8BIM profile

-clip-mask filename associate a clip mask with the image

-clip-path id clip along a named path from the 8BIM profile

-colorize value colorize the image with the fill color

-color-matrix matrix apply color correction to the image

-connected-component connectivity

connected-components uniquely labeled

-contrast enhance or reduce the image contrast

-contrast-stretch geometry

improve contrast by `stretching’ the intensity range

-convolve coefficients

apply a convolution kernel to the image

-cycle amount cycle the image colormap

-deskew threshold straighten an image

-despeckle reduce the speckles within an image

-distort method args

distort images according to given method ad args

-draw string annotate the image with a graphic primitive

-edge radius apply a filter to detect edges in the image

-emboss radius emboss an image

-enhance apply a digital filter to enhance a noisy image

-equalize perform histogram equalization to an image

-evaluate operator value

evaluate an arithmetic, relational, or logical expression

-extent geometry set the image size

-extract geometry extract area from image

-fft implements the discrete Fourier transform (DFT)

-flip flip image vertically

-floodfill geometry color

floodfill the image with color

-flop flop image horizontally

-frame geometry surround image with an ornamental border

-function name apply a function to the image

-gamma value level of gamma correction

-gaussian-blur geometry

reduce image noise and reduce detail levels

-geometry geometry preferred size or location of the image

-grayscale method convert image to grayscale

-hough-lines geometry

identify lines in the image

-identify identify the format and characteristics of the image

-ift implements the inverse discrete Fourier transform (DFT)

-implode amount implode image pixels about the center

-interpolative-resize geometry

resize image using ‘point sampled’ interpolation

-lat geometry local adaptive thresholding

-layers method optimize or compare image layers

-level value adjust the level of image contrast

-level-colors color,color

level image with the given colors

-linear-stretch geometry

improve contrast by `stretching with saturation’ the intensity range

-liquid-rescale geometry

rescale image with seam-carving

-magnify double the size of the image with pixel art scaling

-mean-shift geometry delineate arbitrarily shaped clusters in the image

-median geometry apply a median filter to the image

-mode geometry make each pixel the ‘predominant color’ of the neighborhood

-modulate value vary the brightness, saturation, and hue

-monochrome transform image to black and white

-morphology method kernel

apply a morphology method to the image

-motion-blur geometry

simulate motion blur

-negate replace each pixel with its complementary color

-noise geometry add or reduce noise in an image

-normalize transform image to span the full range of colors

-opaque color change this color to the fill color

-ordered-dither NxN

add a noise pattern to the image with specific amplitudes

-paint radius simulate an oil painting

-perceptible epsilon

pixel value less than |epsilon| become epsilon or -epsilon

-polaroid angle simulate a Polaroid picture

-posterize levels reduce the image to a limited number of color levels

-print string interpret string and print to console

-profile filename add, delete, or apply an image profile

-quantize colorspace reduce colors in this colorspace

-radial-blur angle radial blur the image

-raise value lighten/darken image edges to create a 3-D effect

-random-threshold low,high

random threshold the image

-region geometry apply options to a portion of the image

-render render vector graphics

-repage geometry size and location of an image canvas

-resample geometry change the resolution of an image

-resize geometry resize the image

-roll geometry roll an image vertically or horizontally

-rotate degrees apply Paeth rotation to the image

-sample geometry scale image with pixel sampling

-scale geometry scale the image

-segment values segment an image

-selective-blur geometry

selectively blur pixels within a contrast threshold

-sepia-tone threshold

simulate a sepia-toned photo

-set property value set an image property

-shade degrees shade the image using a distant light source

-shadow geometry simulate an image shadow

-sharpen geometry sharpen the image

-shave geometry shave pixels from the image edges

-shear geometry slide one edge of the image along the X or Y axis

-sigmoidal-contrast geometry

lightness rescaling using sigmoidal contrast enhancement

-sketch geometry simulate a pencil sketch

-solarize threshold negate all pixels above the threshold level

-sparse-color method args

fill in a image based on a few color points

-splice geometry splice the background color into the image

-spread amount displace image pixels by a random amount

-strip strip image of all profiles and comments

-swirl degrees swirl image pixels about the center

-threshold value threshold the image

-thumbnail geometry create a thumbnail of the image

-tile filename tile image when filling a graphic primitive

-tint value tint the image with the fill color

-transform affine transform image

-transparent color
使图片中指定的颜色变为透明。
convert test.png -transparent white transparent.png

-transpose flip image vertically and rotate 90 degrees
-transverse flop image horizontally and rotate 270 degrees
-trim trim image edges
-type type image type
-unique-colors discard all but one of any pixel color
-unsharp geometry sharpen the image
-vignette geometry soften the edges of the image in vignette style
-wave geometry alter an image along a sine wave
-wavelet-denoise threshold

removes noise from the image using a wavelet transform

-white-threshold value

force all pixels above the threshold into white

Image Sequence Operators

-append append an image sequence top to bottom (use +append for left to right)
-clut apply a color lookup table to the image
-coalesce merge a sequence of images
-combine combine a sequence of images
-compare mathematically and visually annotate the difference between an image and its reconstruction
-complex operator perform complex mathematics on an image sequence
-composite composite image
-copy geometry offset,

copy pixels from one area of an image to another

-crop geometry cut out a rectangular region of the image

-deconstruct break down an image sequence into constituent parts

-evaluate-sequence operator

evaluate an arithmetic, relational, or logical expression

-flatten flatten a sequence of images

-fx expression apply mathematical expression to an image channel(s)

-hald-clut apply a Hald color lookup table to the image

-morph value morph an image sequence

-mosaic create a mosaic from an image sequence

-poly terms build a polynomial from the image sequence and the corresponding terms (coefficients and degree pairs)

-process arguments process the image with a custom image filter

-separate separate an image channel into a grayscale image

-smush geometry smush an image sequence together

-write filename write images to this file

Image Stack Operators

-clone indexes clone an image
-delete indexes delete the image from the image sequence
-duplicate count,indexes

duplicate an image one or more times

-insert index insert last image into the image sequence

-reverse reverse image sequence

-swap indexes swap two images in the image sequence

Miscellaneous Options

-debug events display copious debugging information
-distribute-cache port

distributed pixel cache spanning one or more servers

-help print program options

-log format format of debugging information

-list type print a list of supported option arguments

-version print version information

Use any setting or operator as an output-option. Only a limited number of setting are input-option. They
include: -antialias, -caption, -density, -define, -encoding, -font, -pointsize, -size, and -texture as well
as any of the miscellaneous options.

By default, the image format of `file’ is determined by its magic number. To specify a particular image for‐
mat, 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). Specify ‘file’ as ‘-‘ for standard input or output.

SEE ALSO

ImageMagick(1)

参考文献

  • man 1 convert, version 6.9.7.4+dfsg-16