simulate a charcoal drawing. Good parameter values are odd
numbers from 3 to 31
Convolve
apply a convolution kernel to the image. Given the kernel
order, you would supply order*order float values. For
example, the parameter would look like this for a 3x3 Gaussian
kernel:
1, 2, 1, 2, 4, 2, 1, 2, 1
Fx
evaluate expression for each pixel in the specified channel. The Fx expressions includes any combination of the following:
x^y: exponentiation (x^{y})
( ... ): grouping
x*y: multiplication (the asterisk * is optional, for example, 2u or 2(x+y) are acceptable)
x/y: division
x%y: modulo
x+y: addition
x-y: subtraction
x<<y: left shift
x>>y: right shift
x<y: boolean relation, returns value 1.0 if x < y, otherwise 0.0
x<=y: boolean relation, returns value 1.0 if x <= y, otherwise 0.0
x>y: boolean relation, returns value 1.0 if x > y, otherwise 0.0
x>=y: boolean relation, returns value 1.0 if x >= y, otherwise 0.0
x==y: boolean relation, returns value 1.0 if x == y, otherwise 0.0
x!=y: boolean relation, returns value 1.0 if x != y, otherwise 0.0
x&y: binary AND
x|y: binary OR
x&&y: logical AND connective, returns value 1.0 if x > 0 and y > 0, otherwise 0.0
x||y: logical OR connective (inclusive), returns value 1.0 if x > 0 or y > 0 (or both), otherwise 0.0
~x: logical NOT operator, returns value 1.0 if notx > 0, otherwise 0.0
+x: unary plus, returns 1.0*value
-x: unary minus, returns -1.0*value
x?y : z: ternary conditional expression, returns value y if x > 0, otherwise z; only one ternary conditional permitted per statement
x=y: assignment
x;y: statement separator
pi: constant (3.141659...)
e: constant (2.71828...)
QuantumRange: constant maximum pixel value (255 for Q8, 65535 for Q16)
QuantumScale: constant 1.0/QuantumRange
intensity: pixel intensity
hue: pixel hue
saturation: pixel saturation
luminosity: pixel luminosity
red, green, blue, etc.: color names
#ccc, #cbfed0, #b9e1cc00, etc.: color hex values
rgb(), rgba(), cmyk(), cmyka(), hsl(), hsla(): color functions
s,t,u,v,n,i,j,w,h,z,r,g,b,a,o,c,y,m,k: symbols
abs(x): absolute value function
acos(x): arc cosine function
alt(x): sign alternation function (returns 1 if int(x) is even, -1 if int(x) is odd)
asin(x): arc sine function
atan(x): arc tangent function
atan2(y,x): arc tangent function of two variables
ceil(x): smallest integral value not less than argument
cos(x): cosine function
debug(x): print value for debugging
exp(x): natural exponential function (e^{x})
floor(x): largest integral value not greater than argument
int(x): greatest integer function (returns greatest integer less than or equal to x)
ln(x): natural logarithm function
log(x): logarithm base 10
max(x, y): maximum of x and y
min(x, y): minimum of x and y
mod(x, y): floating-point remainder function
pow(x,y): power function (x^{y})
rand(): value uniformly distributed over the interval [0.0, 1.0) with a 2 to the 128th-1 period
sign(x): returns 1 if x is less than 0 otherwise 1
sin(x): sine function
sqrt(x): square root function
tan(x): tangent function
The expression semantics include these rules:
symbols are case insensitive
only one ternary conditional (e.g. x ? y : z) per statement
statements are assignments or the final expression to return
an assignment starts a statement, it is not an operator
assignments to built-ins do not throw errors and have no effect; e.g. r=3.0; r returns the pixel red color value, not 3.0
Implode
implode/explode image pixels about the center. A positive
parameter implodes while a negative parameter explodes the
image.
mosaic
create an mosaic from an image sequence.
Morph
morphs an image sequence. Both the image pixels and size are
linearly interpolated to give the appearance of a meta-morphosis
from one image to the next. Specify the parameter as the number of
in-between images to generate. If you have a single image in your
sequence, the clipboard image is used as the morph anchor.
Oil Paint
simulate an oil painting. Each pixel is replaced by the most
frequent color in a circular neighborhood whose width is specified
as a radius. Good parameter values are odd numbers from 3 to 31
Recolor
translate, scale, shear, or rotate image colors. Although you can use variable sized matrices, typically you use a 5 x 5 for an RGBA image and a 6x6 for CMYKA. Populate the last row with normalized values to translate. For example to double the red component and add 20% to each of red, green, and blue, use:
apply a special effect to the image, similar to the effect achieved in a photo darkroom by sepia toning. Threshold ranges from 0 to MaxRGB and is a measure of the extent of the sepia toning. A threshold of 80% is a good starting point for a reasonable tone.
Shadow
simulate an image shadow. Start with a parameter of 50x5+20+30.
The first value is the percent opacity, the second is the blur sigma value,
and the third and fourth value is the shadow offset relative to the original image
Sketch
simulate a pencil sketch. Try a parameter of 0x20+135.
Solarize
negate all pixels above the threshold level. Specify the
parameter as the percent threshold of the intensity (0 -
99.9%).
Stegano
hide the clipboard image within this image. The parameter is
the offset within the image to begin any hiding.
Stereo
combine two image to create a stereo anaglyph. The left side of
the stereo pair is saved as the red channel of the output image.
The right sife is saved as the green channel. Red-blue stereo
glasses are required to properly view the stereo image.
Swirl
swirl image pixels about the center. Degrees defines the
tightness of the swirl.
Tint
tint the image with the fill color. Tint applies a color vector
to each pixel in the image. The length of the vector is 0 for black
and white and at its maximum for the midtones. The vector weighting
function in between is f(x) = (1-(4.0*((x-0.5)*(x-0.5)))). The
dynamic weighting can be controlled by a constant percentage
(0..100) given as the parameter for tint (e.g. 50%). Usually
de-saturating the image is what you want before tinting.
Vignette
soften the edges of the image in vignette style. Start with a parameter of 0x20.
The first value is the blur radius, the second is the blur sigma value,
and the third and fourth value is the vignette offset relative to the original image
Wave
alter an image along a sine wave. Specify amplitude and
wavelength as the parameter to effect the characteristics of
the wave:
<amplitude>x<wavelength>
See examples of select
ImageMagick Studio effects.