Enumerations
&gt;
Contents
#ChannelType
ChannelType
#ClassType
ClassType
#ColorspaceType
ColorspaceType
#CompositeOperator
CompositeOperator
#CompressionType
CompressionType
#DecorationType
DecorationType
#FillRule
FillRule
#FilterTypes
FilterTypes
#GravityType
GravityType
#ImageType
ImageType
#InterlaceType
InterlaceType
#ChannelType
ChannelType
#LineCap
LineCap
#LineJoin
LineJoin
#NoiseType
NoiseType
#PaintMethod
PaintMethod
#QuantumTypes
QuantumTypes
#RenderingIntent
RenderingIntent
#ResolutionType
ResolutionType
#StorageType
StorageType
#StretchType
StretchType
#StyleType
StyleType
&gt;
ChannelType
ChannelType
is used as an argument when doing color separations. Use
ChannelType
when extracting a layer from an image.
MatteChannel
is useful for extracting the opacity values from an image. Note that an image may be represented in RGB, RGBA, CMYK, or CMYKA, pixel formats and a channel may only be extracted if it is valid for the current pixel format.
ChannelType
Enumeration
Description
UndefinedChannel
Unset value.
RedChannel
Extract red channel (RGB images only)
CyanChannel
Extract cyan channel (CMYK images only)
GreenChannel
Extract green channel (RGB images only)
MagentaChannel
Extract magenta channel (CMYK images only)
BlueChannel
Extract blue channel (RGB images only)
YellowChannel
Extract yellow channel (CMYK images only)
OpacityChannel
Extract matte (opacity values) channel (CMYKA images only)
BlackChannel
Extract black channel (CMYK images only)
MatteChannel
Extract matte (opacity values) channel (RGB images only)
&gt;
ClassType
ClassType
specifies the image storage class.
ClassType
Enumeration
Description
UndefinedClass
Unset value.
DirectClass
Image is composed of pixels which represent literal color values.
PseudoClass
Image is composed of pixels which specify an index in a color palette.
&gt;
ColorspaceType
The ColorspaceType enumeration is used to specify the colorspace that quantization (color reduction and mapping) is done under or to specify the colorspace when encoding an output image. Colorspaces are ways of describing colors to fit the requirements of a particular application (e.g. Television, offset printing, color monitors). Color reduction, by default, takes place in the
RGBColorspace
. Empirical evidence suggests that distances in color spaces such as
YUVColorspace
or
YIQColorspace
correspond to perceptual color differences more closely han do distances in RGB space. These color spaces may give better results when color reducing an image. Refer to
quantize
for more details.
When encoding an output image, the colorspaces
RGBColorspace
,
CMYKColorspace
, and
GRAYColorspace
may be specified. The
CMYKColorspace
option is only applicable when writing TIFF, JPEG, and Adobe Photoshop bitmap (PSD) files.
ColorspaceType
Enumeration
Description
UndefinedColorspace
Unset value.
RGBColorspace
Red-Green-Blue colorspace.
GRAYColorspace
Grayscale colorspace
TransparentColorspace
The Transparent color space behaves uniquely in that it preserves the matte channel of the image if it exists.
OHTAColorspace
XYZColorspace
YCbCrColorspace
YCCColorspace
YIQColorspace
YPbPrColorspace
YUVColorspace
Y-signal, U-signal, and V-signal colorspace. YUV is most widely used to encode color for use in television transmission.
CMYKColorspace
Cyan-Magenta-Yellow-Black colorspace. CYMK is a subtractive color system used by printers and photographers for the rendering of colors with ink or emulsion, normally on a white surface.
sRGBColorspace
&gt;
CompositeOperator
CompositeOperator
is used to select the image composition algorithm used to compose a
composite image
with an
image
. By default, each of the composite image pixels are replaced by the corresponding image tile pixel. Specify
CompositeOperator
to select a different algorithm.
CompositeOperator
Enumeration
Description
UndefinedCompositeOp
Unset value.
OverCompositeOp
The result is the union of the the two image shapes with the
composite image
obscuring
image
in the region of overlap.
InCompositeOp
The result is a simply
composite image
cut by the shape of image. None of the image data of
image
is included in the result.
OutCompositeOp
The resulting image is
composite image
with the shape of
image
cut out.
AtopCompositeOp
The result is the same shape as image
image
, with
composite image
obscuring
image
there the image shapes overlap. Note that this differs from
OverCompositeOp
because the portion of
composite image
outside of
image
's shape does not appear in the result.
XorCompositeOp
The result is the image data from both c
omposite image
and
image
that is outside the overlap region. The overlap region will be blank.
PlusCompositeOp
The result is just the sum of the image data. Output values are cropped to 255 (no overflow). This operation is independent of the matte channels.
MinusCompositeOp
The result of
composite image
-
image
, with overflow cropped to zero. The matte chanel is ignored (set to 255, full coverage).
AddCompositeOp
The result of
composite image
+
image
, with overflow wrapping around (mod 256).
SubtractCompositeOp
The result of
composite image
-
image
, with underflow wrapping around (mod 256). The add and subtract operators can be used to perform reverible transformations.
DifferenceCompositeOp
The result of abs(c
omposite image
-
image
). This is useful for comparing two very similar images.
MultiplyCompositeOp
BumpmapCompositeOp
The result
image
shaded by
composite image.
CopyCompositeOp
The resulting
image
is image replaced with c
omposite image
. Here the matte information is ignored.
CopyRedCompositeOp
The resulting image is the red layer in
image
replaced with the red layer in
composite image
. The other layers are copied untouched.
CopyGreenCompositeOp
The resulting image is the green layer in
image
replaced with the green layer in
composite image
. The other layers are copied untouched.
CopyBlueCompositeOp
The resulting image is the blue layer in
image
replaced with the blue layer in
composite image
. The other layers are copied untouched.
CopyOpacityCompositeOp
The resulting image is the matte layer in
image
replaced with the matte layer in
composite image
. The other layers are copied untouched.
The image compositor requires a matte, or alpha channel in the image for some operations. This extra channel usually defines a mask which represents a sort of a cookie-cutter for the image. This is the case when matte is 255 (full coverage) for pixels inside the shape, zero outside, and between zero and 255 on the boundary. For certain operations, if
image
does not have a matte channel, it is initialized with 0 for any pixel matching in color to pixel location (0,0), otherwise 255 (to work properly
borderWidth
must be 0).
ClearCompositeOp
DissolveCompositeOp
DisplaceCompositeOp
ModulateCompositeOp
ThresholdCompositeOp
&gt;
CompressionType
CompressionType
is used to express the desired compression type when encoding an image. Be aware that most image types only support a sub-set of the available compression types. If the compression type specified is incompatable with the image, ImageMagick selects a compression type compatable with the image type.
CompressionType
Enumeration
Description
UndefinedCompression
Unset value.
NoCompression
No compression
BZipCompression
BZip (Burrows-Wheeler block-sorting text compression algorithm and Huffman coding) as used by bzip2 utilities
FaxCompression
CCITT Group 3 FAX compression
Group4Compression
CCITT Group 4 FAX compression (used only for TIFF)
JPEGCompression
JPEG compression
LZWCompression
Lempel-Ziv-Welch (LZW) compression (caution, patented by Unisys)
RunlengthEncodedCompression
Run-Length encoded (RLE) compression
ZipCompression
Lempel-Ziv compression (LZ77) as used in PKZIP and GNU gzip.
&gt;
DecorationType
The
DecorationType
enumerations are used to specify line decorations of rendered text.
DecorationType
Enumeration
Description
NoDecoration
No decoration
UnderlineDecoration
Underlined text
OverlineDecoration
Overlined text
LineThroughDecoration
Strike-through text
&gt;
EndianType
The
EndianType
enumerations are used to specify the endian option for formats which support it (e.g. TIFF).
EndianType
Enumeration
Description
UndefinedEndian
Not defined (default)
LSBEndian
Little endian (like Intel X86 and DEC Alpha)
MSBEndian
Big endian (like Motorola 68K, Mac PowerPC, & SPARC)
&gt;
FillRule
FillRule
specifies the algorithm which is to be used to determine what parts of the canvas are included inside the shape. See the documentation on SVG's
http://www.w3.org/TR/SVG/painting.html#FillRuleProperty
fill-rule
property for usage details.
FillRule
UndefinedRule
Fill rule not specified
EvenOddRule
See SVG fill-rule
evenodd
rule.
NonZeroRule
See SVG fill-rule
nonzero
rule.
&gt;
FilterTypes
FilterTypes
is used to adjust the filter algorithm used when resizing images. Different filters experience varying degrees of success with various images and can take sipngicantly different amounts of processing time. ImageMagick uses the
LanczosFilter
by default since this filter has been shown to provide the best results for most images in a reasonable amount of time. Other filter types (e.g.
TriangleFilter
) may execute much faster but may show artifacts when the image is re-sized or around diagonal lines. The only way to be sure is to test the filter with sample images.
FilterTypes
Enumeration
Description
UndefinedFilter
Unset value.
PointFilter
Point Filter
BoxFilter
Box Filter
TriangleFilter
Triangle Filter
HermiteFilter
Hermite Filter
HanningFilter
Hanning Filter
HammingFilter
Hamming Filter
BlackmanFilter
Blackman Filter
GaussianFilter
Gaussian Filter
QuadraticFilter
Quadratic Filter
CubicFilter
Cubic Filter
CatromFilter
Catrom Filter
MitchellFilter
Mitchell Filter
LanczosFilter
Lanczos Filter
BesselFilter
Bessel Filter
SincFilter
Sinc Filter
&gt;
GravityType
GravityType
specifies positioning of an object (e.g. text, image) within a bounding region (e.g. an image). Gravity provides a convenient way to locate objects irrespective of the size of the bounding region, in other words, you don't need to provide absolute coordinates in order to position an object. A common default for gravity is
NorthWestGravity
.
GravityType
Enumeration
Description
ForgetGravity
Don't use gravity.
NorthWestGravity
Position object at top-left of region.
NorthGravity
Postiion object at top-center of region
NorthEastGravity
Position object at top-right of region
WestGravity
Position object at left-center of region
CenterGravity
Position object at center of region
EastGravity
Position object at right-center of region
SouthWestGravity
Position object at left-bottom of region
SouthGravity
Position object at bottom-center of region
SouthEastGravity
Position object at bottom-right of region
&gt;
ImageType
ImageType
indicates the type classification of the image.
ImageType
Enumeration
Description
UndefinedType
Unset value.
BilevelType
Monochrome image
GrayscaleType
Grayscale image
GrayscaleMatteType
Grayscale image with opacity
PaletteType
Indexed color (palette) image
PaletteMatteType
Indexed color (palette) image with opacity
TrueColorType
Truecolor image
TrueColorMatteType
Truecolor image with opacity
ColorSeparationType
Cyan/Yellow/Magenta/Black (CYMK) image
&gt;
InterlaceType
InterlaceType
specifies the ordering of the red, green, and blue pixel information in the image. Interlacing is usually used to make image information available to the user faster by taking advantage of the space vs time tradeoff. For example, interlacing allows images on the Web to be recognizable sooner and satellite images to accumulate/render with image resolution increasing over time.
Use
LineInterlace
or
PlaneInterlace
to create an interlaced GIF or progressive JPEG image.
InterlaceType
Enumeration
Description
UndefinedInterlace
Unset value.
NoInterlace
Don't interlace image (RGBRGBRGBRGBRGBRGB...)
LineInterlace
Use scanline interlacing (RRR...GGG...BBB...RRR...GGG...BBB...)
PlaneInterlace
Use plane interlacing (RRRRRR...GGGGGG...BBBBBB...)
PartitionInterlace
Similar to plane interlaing except that the different planes are saved to individual files (e.g. image.R, image.G, and image.B)
&gt;
ChannelType
ChannelType
is used as an argument when doing color separations. Use
ChannelType
when extracting a layer from an image.
MatteLayer
is useful for extracting the opacity values from an image.
ChannelType
Enumeration
Description
UndefinedLayer
Unset value.
RedLayer
Select red layer
GreenLayer
Select green layer
BlueLayer
Select blue layer
MatteLayer
Select matte (opacity values) layer
&gt;
LineCap
The
LineCap
enumerations specify shape to be used at the end of open subpaths when they are stroked. See SVG's '
http://www.w3.org/TR/SVG/painting.html#StrokeLinecapProperty
stroke-linecap'
for examples.
LineCap
Enumeration
Description
UndefinedCap
Unset value.
ButtCap
Square ending.
RoundCap
Rounded ending (half-circle end with radius of 1/2 stroke width).
SquareCap
Square ending, extended by 1/2 the stroke width at end.
&gt;
LineJoin
The
LineJoin
enumerations specify the shape to be used at the corners of paths or basic shapes when they are stroked. See SVG's '
http://www.w3.org/TR/SVG/painting.html#StrokeLinejoinProperty
stroke-linejoin'
for examples.
ChannelType
Enumeration
Description
UndefinedJoin
Unset value.
MiterJoin
Sharp-edged join
RoundJoin
Rounded-edged join
BevelJoin
Beveled-edged join
&gt;
NoiseType
NoiseType
is used as an argument to select the type of noise to be added to the image.
NoiseType
Enumeration
Description
UniformNoise
Uniform noise
GaussianNoise
Gaussian noise
MultiplicativeGaussianNoise
Multiplicative Gaussian noise
ImpulseNoise
Impulse noise
LaplacianNoise
Laplacian noise
PoissonNoise
Poisson noise
&gt;
PaintMethod
PaintMethod
specifies how pixel colors are to be replaced in the image. It is used to select the pixel-filling algorithm employed.
PaintMethod
Enumeration
Description
PointMethod
Replace pixel color at point.
ReplaceMethod
Replace color for all image pixels matching color at point.
FloodfillMethod
Replace color for pixels surrounding point until encountering pixel that fails to match color at point.
FillToBorderMethod
Replace color for pixels surrounding point until encountering pixels matching border color.
ResetMethod
Replace colors for
all
pixels in image with pen color.
&gt;
QuantumTypes
QuantumTypes
is used to indicate the source or destination format of entire pixels, or components of pixels ("Quantums") while they are being read, or written to, a pixel cache. The validity of these format specifications depends on whether the Image pixels are in RGB format, RGBA format, or CMYK format. The pixel Quantum size is determined by the Image depth (eight or sixteen bits).
RGB(A) Image Quantums
Enumeration
Description
IndexQuantum
PseudoColor colormap indices (valid only for image with colormap)
RedQuantum
Red pixel Quantum
GreenQuantum
Green pixel Quantum
BlueQuantum
Blue pixel Quantum
OpacityQuantum
Opacity (Alpha) Quantum
CMY(K) Image Quantum
Enumeration
Description
CyanQuantum
Cyan pixel Quantum
MagentaQuantum
Magenta pixel Quantum
YellowQuantum
Yellow pixel Quantum
BlackQuantum
Black pixel Quantum
Grayscale Image Quantums
Enumeration
Description
GrayQuantum
Gray pixel
GrayOpacityQuantum
Pixel opacity
Entire Pixels (Expressed in Byte Order)
Enumeration
Description
RGBQuantum
RGB pixel (24 or 48 bits)
RGBAQuantum
RGBA pixel (32 or 64 bits)
CMYKQuantum
CMYK pixel (32 or 64 bits)
&gt;
RenderingIntent
Rendering intent is a concept defined by
http://www.color.org/
ICC
Spec ICC.1:1998-09, "File Format for Color Profiles". ImageMagick uses
RenderingIntent
in order to support ICC Color Profiles.
From the specification: "Rendering intent specifies the style of reproduction to be used during the evaluation of this profile in a sequence of profiles. It applies specifically to that profile in the sequence and not to the entire sequence. Typically, the user or application will set the rendering intent dynamically at runtime or embedding time."
RenderingIntent
Enumeration
Description
UndefinedIntent
Unset value.
SaturationIntent
A rendering intent that specifies the saturation of the pixels in the image is preserved perhaps at the expense of accuracy in hue and lightness.
PerceptualIntent
A rendering intent that specifies the full gamut of the image is compressed or expanded to fill the gamut of the destination device. Gray balance is preserved but colorimetric accuracy might not be preserved.
AbsoluteIntent
Absolute colorimetric
RelativeIntent
Relative colorimetric
&gt;
ResolutionType
By default, ImageMagick defines resolutions in pixels per inch.
ResolutionType
provides a means to adjust this.
ResolutionType
Enumeration
Description
UndefinedResolution
Unset value.
PixelsPerInchResolution
Density specifications are specified in units of pixels per inch (english units).
PixelsPerCentimeterResolution
Density specifications are specified in units of pixels per centimeter (metric units).
&gt;
StorageType
The
StorageType
enumerations are used to specify the storage format of pixels in the source or destination pixel array.
StorageType
Enumeration
Description
CharPixel
Character type
ShortPixel
Short type
IntegerPixel
Integer type
FloatPixel
Float type
DoublePixel
Double type
&gt;
StretchType
The
StretchType
enumerations are used to specify the relative width of a font to the regular width for the font family. If the width is not important, the
AnyStretch
enumeration may be specified for a wildcard match.
StretchType
Enumeration
Description
AnyStretch
Wildcard match for font stretch
NormalStretch
Normal width font
UltraCondensedStretch
Ultra-condensed (narrowest) font
ExtraCondensedStretch
Extra-condensed font
CondensedStretch
Condensed font
SemiCondensedStretch
Semi-Condensed font
SemiExpandedStretch
Semi-Expanded font
ExpandedStretch
Expanded font
ExtraExpandedStretch
Extra-Expanded font
UltraExpandedStretch
Ultra-expanded (widest) font
&gt;
StyleType
The
StyleType
enumerations are used to specify the style (e.g. Italic) of a font. If the style is not important, the
AnyStyle
enumeration may be specified for a wildcard match.
StyleType
Enumeration
Description
AnyStyle
Wildcard match for font style
NormalStyle
Normal font style
ItalicStyle
Italic font style
ObliqueStyle
Oblique font style
