Contents |
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Introduction |
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Installation |
Back to ContentsThe following instructions for Unix apply only to the unbundled PerlMagick as obtained from CPAN. PerlMagick is included as a subdirectory (PerlMagick) of the ImageMagick source distribution, and may be configured and built using the instructions provided in the ImageMagick distribution's README.txt file. It is usually most convenient to install PerlMagick as part of the ImageMagick distribution.
ImageMagick must already be installed on your system. Next, get the PerlMagick distribution corresponding to the installed ImageMagick distribution (e.g. PerlMagick 5.39 for ImageMagick 5.3.0) and unpack it as shown below:
gunzip -c PerlMagick-5.39.tar.gz | tar -xvf -Next, edit Makefile.PL and change LIBS and INC to include the appropriate path information to the required libMagick library. You will also need paths to JPEG, PNG, TIFF, etc. delegates if they were included with your installed version of ImageMagick. Build and install it like this:
cd PerlMagickperl Makefile.PLFor Unix, you typically need to be root to install the software. There are ways around this. Consult the Perl manual pages for more information.
make
make installWindows XP / Windows 2000
ImageMagick must already be installed on your system. Also, the ImageMagick source distribution for Windows 2000 is required. You must also have the nmake from the Visual C++ or J++ development environment. Copy \bin\IMagick.dll and \bin\X11.dll to a directory in your dynamic load path such as c:\perl\site\5.00502 . Next, type
cd PerlMagick
copy Makefile.nt Makefile.PL
perl Makefile.PL
nmake
nmake installSee the PerlMagick Windows HowTo page for further installation instructions.
Running the Regression Tests
To verify a correct installation, type
make testUse nmake test under Windows. There are a few demonstration scripts available to exercise many of the functions PerlMagick can perform. Typecd demoYou are now ready to utilize the PerlMagick methods from within your Perl scripts.
make
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Overview |
Some of the PerlMagick methods require external programs such as Ghostscript. This may require an explicit path in your PATH environment variable to work properly. For example,
use Image::Magick;The new() method takes the same parameters as SetAttribute . For example,
$image=Image::Magick->new;$image=Image::Magick->new(size=>'384x256');Next you will want to read an image or image sequence, manipulate it, and then display or write it. The input and output methods for PerlMagick are defined in Read or Write an Image. See Set an Image Attribute for methods that affect the way an image is read or written. Refer to Manipulate an Image for a list of methods to transform an image. Get an Image Attribute describes how to retrieve an attribute for an image. Refer to Create an Image Montage for details about tiling your images as thumbnails on a background. Finally, some methods do not neatly fit into any of the categories just mentioned. Review Miscellaneous Methods for a list of these methods.Once you are finished with a PerlMagick object you should consider destroying it. Each image in an image sequence is stored in virtual memory. This can potentially add up to mega-bytes of memory. Upon destroying a PerlMagick object, the memory is returned for use by other Perl methods. The recommended way to destroy an object is with undef:
undef $image;To delete all the images but retain the Image::Magick object use@$image = ();and finally, to delete a single image from a multi-image sequence, useundef $image->[x];The next section illustrates how to use various PerlMagick methods to manipulate an image sequence.$ENV{PATH}='/bin:/usr/bin:/usr/local/bin';
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Example Script |
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#!/usr/local/bin/perlThe script reads three images, crops them, and writes a single image as a GIF animation sequence. In many cases you may want to access individual images of a sequence. The next example illustrates how this is done:
use Image::Magick;
my($image, $x);
$image = Image::Magick->new;
$x = $image->Read('girl.png', 'logo.png', 'rose.png');
warn "$x" if "$x";
$x = $image->Crop(geometry=>'100x100"+1"00"+1"00');
warn "$x" if "$x";
$x = $image->Write('x.png');
warn "$x" if "$x";#!/usr/local/bin/perlSuppose you want to start out with a 100 by 100 pixel white canvas with a red pixel in the center. Try
use Image::Magick;
my($image, $p, $q);
$image = new Image::Magick;
$image->Read('x1.png');
$image->Read('j*.jpg');
$image->Read('k.miff[1, 5, 3]');
$image->Contrast();
for ($x = 0; $image->[x]; $x++)
{
$image->[x]->Frame('100x200') if $image->[x]->Get('magick') eq 'GIF';
undef $image->[x] if $image->[x]->Get('columns') < 100;
}
$p = $image->[1];
$p->Draw(stroke=>'red', primitive=>'rectangle', points=>20,20 100,100');
$q = $p->Montage();
undef $image;
$q->Write('x.miff');$image = Image::Magick->new;Or suppose you want to convert your color image to grayscale:
$image->Set(size=>'100x100');
$image->ReadImage('xc:white');
$image->Set('pixel[49,49]'=>'red');$image->Quantize(colorspace=>'gray');Here we annotate an image with a Taipai TrueType font:$text = 'Works like magick!';Other clever things you can do with a PerlMagick objects include
$image->Annotate(font=>'kai.ttf', pointsize=>40, fill=>'green', text=>$text);$i = $#$p"+1"; # return the number of images associated with object p
push(@$q, @$p); # push the images from object p onto object q
@$p = (); # delete the images but not the object p
$p->Convolve([1, 2, 1, 2, 4, 2, 1, 2, 1]); # 3x3 Gaussian kernel
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Read or Write an Image |
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Read or Write Methods Method Parameters Return Value Description Read one or more filenames the number of images read read an image or image sequence Write filename the number of images written write an image or image sequence Display server name the number of images displayed display the image or image sequence to an X server Animate server name the number of images animated animate image sequence to an X server For convenience, methods Write(), Display(), and Animate() can take any parameter that SetAttribute knows about. For example,
$image->Write(filename=>'image.png', compression=>'None');Use - as the filename to method Read() to read from standard in or to method Write() to write to standard out:binmode STDOUT;To read an image in the GIF format from a PERL filehandle, use:
$image->Write('png:-');$image = Image::Magick->new;To write an image in the PNG format to a PERL filehandle, use:
open(IMAGE, 'image.gif');
$image->Read(file=>\*IMAGE);
close(IMAGE);$filename = "image.png";If %0Nd, %0No, or %0Nx appears in the filename, it is interpreted as a printf format specification and the specification is replaced with the specified decimal, octal, or hexadecimal encoding of the scene number. For example,
open(IMAGE, ">$filename");
$image->Write(file=>\*IMAGE, filename=>$filename);
close(IMAGE);image%03d.miffconverts files image000.miff, image001.miff, etc.
You can optionally add Image to any method name. For example, ReadImage() is an alias for method Read().
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Manipulate an Image |
Back to Contentsproduces an annotation of MIFF:bird.miff 512x480 for an image titled bird.miff and whose width is 512 and height is 480.
$image->Crop(geometry=>'100x100"+1"0+20');And here is a list of other image manipulation methods you can call:
$image->[x]->Frame("100x200");
Image Manipulation Methods Method Parameters Description AddNoise noise=>{Uniform, Gaussian, Multiplicative, Impulse, Laplacian, Poisson} add noise to an image AffineTransform affine=>array of float values, translate=>float, float, scale=> float, float, rotate=>float, skewX=>float, skewY=>float affine transform image Edge radius=>double enhance edges within the image with a convolution filter of the given radius. Annotate text=>string, font=>string, family=>string, style=>{Normal, Italic, Oblique, Any}, stretch=>{Normal, UltraCondensed, ExtraCondensed, Condensed, SemiCondensed, SemiExpanded, Expanded, ExtraExpanded, UltraExpanded}, weight=>integer, pointsize=>integer, density=>geometry, stroke=> color name, strokewidth=>integer, fill=>color name, undercolor=>color name, geometry=>geometry, gravity=>{NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast}, antialias=>{true, false}, x=>integer, y=>integer, affine=>array of float values, translate=>float, float, scale=>float, float, rotate=>float. skewX=>float, skewY=> float, align=>{Left, Center, Right}, encoding=>{None, SJIScode, Unicode}, unicode=>{True, False}, annotate an image with text. See QueryFontMetrics to get font metrics without rendering any text. Blur geometry=>geometry, radius=>double, sigma=> double blur the image with a gaussian operator of the given radius and standard deviation (sigma). Border geometry=>geometry, width=>integer, height=> integer, fill=color name surround the image with a border of color Channel channel={Red, Cyan, Green, Magenta, Blue, Yellow, Opacity, Black} extract a channel from the image Charcoal order=>integer simulate a charcoal drawing Chop geometry=>geometry, width=>integer, height=> integer, x=>integer, y=>integer chop an image Coalesce
merge a sequence of images Clip
apply any clipping path information as an image clip mask. ColorFloodfill geometry=>geometry, x=>integer, y=>integer , fill=color name, bordercolor= color name changes the color value of any pixel that matches the color of the target pixel and is a neighbor. If you specify a border color, the color value is changed for any neighbor pixel that is not that color. Colorize fill=>color name, opacity=>string colorize the image with the fill color Comment string add a comment to your image Composite image=>image-handle, compose=>{Over, In, Out, Atop, Xor, Plus, Minus, Add, Subtract, Difference, Multiply, Bumpmap, Copy, CopyRed, CopyGreen, CopyBlue, CopyMatte, Dissolve, Clear, Displace, Modulate, Threshold}, mask=>image-handle, geometry=>geometry, x=>integer, y=>integer, gravity=>{NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast}, opacity=>integer, tile=>{True, False}, rotate=>double, color=>color name composite one image onto another Contrast sharpen=>{True, False} enhance or reduce the image contrast Convolve coefficients=>array of float values apply a convolution kernel to the image. Given a kernel order , you would supply order*order float values (e.g. 3x3 implies 9 values). Crop geometry=>geometry, width=>integer, height=> integer, x=>integer, y=>integer crop an image CycleColormap amount=>integer displace image colormap by amount Deconstruct
break down an image sequence into constituent parts Despeckle
reduce the speckles within an image Draw primitive=>{point, line, rectangle, arc, ellipse, circle, path, polyline, polygon, bezier, color, matte, text, @filename}, points=>string , method={Point, Replace, Floodfill, FillToBorder, Reset}, stroke=> color name, fill=>color name, tile=>image-handle, strokewidth=>float, antialias=>{true, false}, bordercolor=>color name, x=> float, y=>float, affine=>array of float values, translate=>float, float, scale=> float, float, rotate=>float. skewX=>float, skewY=> float annotate an image with one or more graphic primitives Edge radius=>double enhance edges within the image with a convolution filter of the given radius. Emboss geometry=>geometry, radius=>double, sigma=> double emboss the image with a convolution filter of the given radius and standard deviation (sigma). Enhance
apply a digital filter to enhance a noisy image Equalize
perform histogram equalization to the image Flatten
flatten a sequence of images Flip
create a mirror image by reflecting the image scanlines in the vertical direction Flop
create a mirror image by reflecting the image scanlines in the horizontal direction Frame geometry=>geometry, width=>integer, height=> integer, inner=>integer, outer=>integer, fill=> color name surround the image with an ornamental border Gamma gamma=>string, red=>double, green=>double , blue=>double gamma correct the image Implode amount=>double implode image pixels about the center Label string assign a label to an image Level level=>string, 'black-point'=>double, 'mid-point'=>double, 'white-point'=>double adjust the level of image contrast Magnify
double the size of an image Map image=>image-handle, dither={True, False} choose a particular set of colors from this image MatteFloodfill geometry=>geometry, x=>integer, y=>integer , matte=integer, bordercolor=color name changes the matte value of any pixel that matches the color of the target pixel and is a neighbor. If you specify a border color, the matte value is changed for any neighbor pixel that is not that color. MedianFilter radius=>double replace each pixel with the median intensity pixel of a neighborhood. Minify
half the size of an image Modulate brightness=>double, saturation=>double, hue=> double vary the brightness, saturation, and hue of an image by the specified percentage MotionBlur geometry=>geometry, radius=>double, sigma=> double, angle=>double blur the image with a gaussian operator of the given radius and standard deviation (sigma) at the given angle to simulate the effect of motion Border Negate gray=>{True, False} replace every pixel with its complementary color (white becomes black, yellow becomes blue, etc.) Normalize
transform image to span the full range of color values OilPaint radius=>integer simulate an oil painting Opaque color=>color name, fill=> color name change this color to the fill color within the image Quantize colors=>integer, colorspace=>{RGB, Gray, Transparent, OHTA, XYZ, YCbCr, YIQ, YPbPr, YUV, CMYK}, treedepth=> integer, dither=>{True, False}, measure_error=>{True, False}, global_colormap=>{True, False} preferred number of colors in the image Profile name=>{ICM, IPTC}, profile=>blob add or remove ICC or IPTC image profile Raise geometry=>geometry, width=>integer, height=> integer, x=>integer, y=>integer, raise=>{True, False} lighten or darken image edges to create a 3-D effect ReduceNoise radius=>double reduce noise in the image with a noise peak elimination filter Resize geometry=>geometry, width=>integer, height=> integer, filter=>{Point, Box, Triangle, Hermite, Hanning, Hamming, Blackman, Gaussian, Quadratic, Cubic, Catrom, Mitchell, Lanczos, Bessel, Sinc}, blur=>double scale image to desired size. Specify blur > 1 for blurry or < 1 for sharp Roll geometry=>geometry, x=>integer, y=>integer roll an image vertically or horizontally Rotate degrees=>double, color=>color name rotate an image Sample geometry=>geometry, width=>integer, height=> integer scale image with pixel sampling Scale geometry=>geometry, width=>integer, height=> integer scale image to desired size Segment colorspace=>{RGB, Gray, Transparent, OHTA, XYZ, YCbCr, YCC, YIQ, YPbPr, YUV, CMYK}, verbose={True, False}, cluster=>double, smooth= double segment an image by analyzing the histograms of the color components and identifying units that are homogeneous Shade geometry=>geometry, azimuth=>double, elevation=> double, color=>{true, false} shade the image using a distant light source Sharpen geometry=>geometry, radius=>double, sigma=> double sharpen the image with a gaussian operator of the given radius and standard deviation (sigma). Shave geometry=>geometry, width=>integer, height=> integer shave pixels from the image edges Shear geometry=>geometry, x=>double, y=>double color=>color name shear the image along the X or Y axis by a positive or negative shear angle Signature
generate an SHA-256 message digest for the image pixel stream Solarize threshold=>integer negate all pixels above the threshold level Spread amount=>integer displace image pixels by a random amount Stereo image=>image-handle composites two images and produces a single image that is the composite of a left and right image of a stereo pair Stegano image=>image-handle, offset=integer hide a digital watermark within the image Swirl degrees=>double swirl image pixels about the center Texture texture=>image-handle name of texture to tile onto the image background Threshold threshold=>integer threshold the image Transparent color=>color name make this color transparent within the image Trim
remove edges that are the background color from the image UnsharpMask geometry=>geometry, radius=>double, sigma=> double, amount=>double, threshold=>double sharpen the image with the unsharp mask algorithm. Wave geometry=>geometry, amplitude=>double, wavelength=> double alter an image along a sine wave Note, that the geometry parameter is a short cut for the width and height parameters (e.g. geometry=>'106x80' is equivalent to width=>106, height=>80 ).
You can specify @filename in both Annotate() and Draw(). This reads the text or graphic primitive instructions from a file on disk. For example,
$image->Draw(fill=>'red', primitive=>'rectangle',Is eqivalent to
points=>'20,20 100,100 40,40 200,200 60,60 300,300');$image->Draw(fill=>'red', primitive=>'@draw.txt');Where draw.txt is a file on disk that contains this:rectangle 20, 20 100, 100The text parameter for methods, Annotate(), Comment(), Draw(), and Label() can include the image filename, type, width, height, or other image attribute by embedding these special format characters:
rectangle 40, 40 200, 200
rectangle 60, 60 300, 300%b file sizeFor example,
%d comment
%d directory
%e filename extension
%f filename
%h height
%m magick
%p page number
%s scene number
%t top of filename
%w width
%x x resolution
%y y resolution
\n newline
\r carriage returntext=>"%m:%f %wx%h"
You can optionally add Image to any method name. For example, TrimImage() is an alias for method Trim().
Most of the attributes listed above have an analog in convert. See the documentation for a more detailed description of these attributes.
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Set an Image Attribute |
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$image->Set(dither=>'True');And here is a list of all the image attributes you can set:
$image->[$x]->Set(delay=>3);
Image Attributes Attribute Values Description adjoin {True, False} join images into a single multi-image file antialias {True, False} remove pixel aliasing background color name image background color blue-primary x-value, y-value chromaticity blue primary point (e.g. 0.15, 0.06) bordercolor color name set the image border color cache-threshold integer Image pixels are stored in memory until your computers memory is consumed. Subsequent pixel operations are cached to disk. Operations to memory are significantly faster but if your computer does not have a sufficient amount of free memory you may want to set this threshold to a small megabyte value (e.g. 8). clip-mask image Associate a clip mask with the image. colormap[i] color name color name (e.g. red) or hex value (e.g. #ccc) at position i colorspace {RGB, CMYK} type of colorspace comment string Append to the image comment. compression None, BZip, Fax, Group4, JPEG, LosslessJPEG, LZW, RLE, Zip type of image compression delay integer this many 1/100ths of a second\fP must expire before displaying the next image in a sequence density geometry vertical and horizontal resolution in pixels of the image dispose {0, 1, 2, 3} GIF disposal method dither {True, False} apply error diffusion to the image display string specifies the X server to contact file filehandle set the image filehandle filename string set the image filename fill color The fill color paints any areas inside the outline of drawn shape. font string use this font when annotating the image with text fuzz integer colors within this distance are considered equal Gravity Forget, NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast type of image gravity green-primary x-value, y-value chromaticity green primary point (e.g. 0.3, 0.6) index[x, y] string colormap index at position (x, y) interlace {None, Line, Plane, Partition} the type of interlacing scheme iterations integer add Netscape loop extension to your GIF animation label string Append to the image label. loop integer add Netscape loop extension to your GIF animation magick string set the image format matte {True, False} True if the image has transparency mattecolor color name set the image matte color monochrome {True, False} transform the image to black and white page { Letter, Tabloid, Ledger, Legal, Statement, Executive, A3, A4, A5, B4, B5, Folio, Quarto, 10x14} or geometry preferred size and location of an image canvas pixel[x, y] string hex value (e.g. #ccc) at position (x, y) pointsize integer pointsize of the Postscript or TrueType font preview { Rotate, Shear, Roll, Hue, Saturation, Brightness, Gamma, Spiff, Dull, Grayscale, Quantize, Despeckle, ReduceNoise, AddNoise, Sharpen, Blur, Threshold, EdgeDetect, Spread, Solarize, Shade, Raise, Segment, Swirl, Implode, Wave, OilPaint, CharcoalDrawing, JPEG} type of preview for the Preview image format quality integer JPEG/MIFF/PNG compression level red-primary x-value, y-value chromaticity red primary point (e.g. 0.64, 0.33) rendering-intent {Undefined, Saturation, Perceptual, Absolute, Relative} the type of rendering intent sampling-factor geometry horizontal and vertical sampling factor scene integer image scene number subimage integer subimage of an image sequence subrange integer number of images relative to the base image server string specifies the X server to contact size string width and height of a raw image stroke color The stroke color paints along the outline of a shape. tile string tile name texture string name of texture to tile onto the image background type {Bilevel, Grayscale, GrayscaleMatte, Palette, PaletteMatte, TrueColor, TrueColorMatte, ColorSeparation, ColorSeparationMatte, Optimize } image type units { Undefined, PixelsPerInch, PixelsPerCentimeters} units of image resolution verbose {True, False} print detailed information about the image white-point x-value, y-value chromaticity white point (e.g. 0.3127, 0.329) Note, that the geometry parameter is a short cut for the width and height parameters (e.g. geometry=>'106x80' is equivalent to width=>106, height=>80).
SetAttribute() is an alias for method Set().
Most of the attributes listed above have an analog in convert. See the documentation for a more detailed description of these attributes.
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Get an Image Attribute |
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($a, $b, $c) = $image->Get('colorspace', 'magick', 'adjoin');In addition to all the attributes listed in Set an Image Attribute , you can get these additional attributes:
$width = $image->[3]->Get('columns');
Image Attributes Attribute Values Description base-columns integer base image width (before transformations) base-filename string base image filename (before transformations) base-rows integer base image height (before transformations) class {Direct, Pseudo} image class colors integer number of unique colors in the image comment string image comment columns integer image width depth integer image depth directory string tile names from within an image montage error double the mean error per pixel computed when an image is color reduced filesize integer number of bytes of the image on disk format string get the descriptive image format gamma double gamma level of the image geometry string image geometry height integer the number of rows or height of an image id integer ImageMagick registry id label string image label maximum-error double the normalized max error per pixel computed when an image is color reduced mean-error double the normalized mean error per pixel computed when an image is color reduced montage geometry tile size and offset within an image montage rows integer the number of rows or height of an image signature string SHA-256 message digest associated with the image pixel stream taint {True, False} True if the image has been modified width integer the number of columns or width of an image x-resolution integer x resolution of the image y-resolution integer y resolution of the image GetAttribute() is an alias for method Get().
Most of the attributes listed above have an analog in convert. See the documentation for a more detailed description of these attributes.
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Create an Image Montage |
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$image->Montage(geometry=>'160x160', tile=>'2x2', texture=>'granite:');And here is a list of Montage() parameters you can set:
Montage Parameters Parameter Values Description background color name background color name borderwidth integer image border width compose {Over, In, Out, Atop, Xor, Plus, Minus, Add, Subtract, Difference, Bumpmap, Copy, Mask, Dissolve, Clear, Displace} composite operator filename string name of montage image fill color name fill color for annotations font string X11 font name frame geometry surround the image with an ornamental border geometry geometry preferred tile and border size of each tile of the composite image gravity {NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast} direction image gravitates to within a tile ICM blob color information profile IPTC blob newswire information profile label string assign a label to an image mode {Frame, Unframe, Concatenate} thumbnail framing options pointsize integer pointsize of the Postscript or TrueType font shadow {True, False} add a shadow beneath a tile to simulate depth stroke color name stroke color for annotations texture string name of texture to tile onto the image background tile geometry number of tiles per row and column title string assign a title to the image montage transparent string make this color transparent within the image Note, that the geometry parameter is a short cut for the width and height parameters (e.g. geometry=>'106x80' is equivalent to width=>106, height=>80).
MontageImage() is an alias for method Montage().
Most of the attributes listed above have an analog in montage. See the documentation for a more detailed description of these attributes.
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Working with Blobs |
ImageToBlob() returns the image data in their respective formats. You can then print it, save it to an ODBC database, write it to a file, or pipe it to a display program:
Blob Methods Method Parameters Return Value Description ImageToBlob any image attribute an array of image data in the respective image format convert an image or image sequence to an array of blobs BlobToImage one or more blobs the number of blobs converted to an image convert one or more blobs to an image @blobs = $image->ImageToBlob();Method BlobToImage() returns an image or image sequence converted from the supplied blob:
open(DISPLAY,"| display -") || die;
binmode DISPLAY;
print DISPLAY $blobs[0];
close DISPLAY;@blob=$db->GetImage();
$image=Image::Magick->new(magick=>'jpg');
$image->BlobToImage(@blob);
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Miscellaneous Methods |
Back to ContentsCall QueryColor() with no parameters to return a list of known colors names or specify one or more color names to get these attributes: red, green, blue, and opacity value.
$p = $image->Append(stack=>{true,false});appends all the images associated with object $image. By default, images are stacked left-to-right. Set stack to True to stack them top-to-bottom.The Average() method averages a set of images. For example,
$p = $image->Average();averages all the images associated with object $image.The Clone() method copies a set of images. For example,
$p = $image->Clone();copies all the images from object $q to $p. You can use this method for single or multi-image sequences.The Morph() method morphs a set of images. Both the image pixels and size are linearly interpolated to give the appearance of a meta-morphosis from one image to the next:
$p = $image->Morph(frames=>integer);where frames is the number of in-between images to generate. The default is 1.Mosaic() creates an mosaic from an image sequence.
Method Mogrify() is a single entry point for the image manipulation methods (Manipulate an Image). The parameters are the name of a method followed by any parameters the method may require. For example, these calls are equivalent:
$image->Crop('340x256+0+0');Method MogrifyRegion() applies a transform to a region of the image. It is similiar to Mogrify() but begins with the region geometry. For example, suppose you want to brighten a 100x100 region of your image at location (40, 50):
$image->Mogrify('crop', '340x256+0+0');$image->MogrifyRegion('100x100+40+50', 'modulate', brightness=>50);Ping() is a convenience method that returns information about an image without having to read the image into memory. It returns the width, height, file size in bytes, and the file format of the image. You can specify more than one filename but only one filehandle:($width, $height, $size, $format) = $image->Ping('logo.png'); ($width, $height, $size, $format) = $image->Ping(file=>\*IMAGE); ($width, $height, $size, $format) = $image->Ping(blob=>$blob);This is a more efficient and less memory intensive way to query if an image exists and what its characteristics are.To have full control over text positioning you need font metric information. Use
($x_ppem, $y_ppem, $ascender, $descender, $width, $height, $max_advance) =Where parameters is any parameter of the Annotate method. The return values are
$image->QueryFontMetrics(parameters);
- character width
- character height
- ascender
- descender
- text width
- text height
- maximum horizontal advance
QueryColorName() accepts a color value and returns its respective name or hex value;
@colors = $image->QueryColor();
($red, $green, $blue, $opacity) = $image->QueryColor('cyan');
($red, $green, $blue, $opacity) = $image->QueryColor('#716bae');
Call QueryFont() with no parameters to return a list of known fonts or specify one or more font names to get these attributes: font name, description, family, style, stretch, weight, encoding, foundry, format, metrics, and glyphs values.
$name = $image->QueryColorName('rgba(80,60,0,0)');
Call QueryFormat() with no parameters to return a list of known image formats or specify one or more format names to get these attributes: adjoin, blob support, raw, decoder, encoder, description, and module.
@fonts = $image->QueryFont();
$weight = ($image->QueryFont('Helvetica'))[5];
@formats = $image->QueryFormat();
($adjoin, $blob_support, $raw, $decoder, $encoder, $description, $module) = $image->QueryFormat('gif');Use RemoteCommand() to send a command to an already running display or animate application. The only parameter is the name of the image file to display or animate.
Finally, the Transform() method accepts a fully-qualified geometry specification for cropping or resizing one or more images. For example,
$p = $image->Transform(crop=>'100x100');You can optionally add Image to any method name above. For example, PingImage() is an alias for method Ping().
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Handling Errors |
$x = $image->Read(...);
warn "$x" if "$x"; # print the error message
$x =~ /(\d+)/;
print $1; # print the error number
print 0+$x; # print the number of images read
$x = $image->Crop(...);
warn "$x" if "$x"; # print the error message
$x =~ /(\d+)/;
print $1; # print the error number
$x = $image->Montage(...);
warn "$x" if !ref($x); # print the error message
$x =~ /(\d+)/;
print $1; # print the error number
Here is an example error message:
The following illustrates how you can use a numeric status code:Error 400: Memory allocation failedBelow is a list of error and warning codes:
Error and Warning Codes Code Mnemonic Description 0 Success method completed without an error or warning 300 ResourceLimitWarning a program resource is exhausted (e.g. not enough memory) 305 TypeWarning A font is unavailable; a substitution may have occured 310 OptionWarning a command-line option was malformed 315 DelegateWarning an ImageMagick delegate returned a warning 320 MissingDelegateWarning the image type can not be read or written because the appropriate Delegate is missing 325 CorruptImageWarning the image file may be corrupt 330 FileOpenWarning the image file could not be opened 335 BlobWarning a binary large object could not be allocated 340 StreamWarning there was a problem reading or writing from a stream 345 CacheWarning pixels could not be saved to the pixel cache 385 XServerWarning an X resource is unavailable 390 RegistryWarning there was a problem getting or setting the registry 395 ConfigurationWarning there was a problem getting a configuration file 400 ResourceLimitError a program resource is exhausted (e.g. not enough memory) 405 TypeError A font is unavailable; a substitution may have occured 410 OptionError a command-line option was malformed 415 DelegateError an ImageMagick delegate returned a warning 420 MissingDelegateError the image type can not be read or written because the appropriate Delegate is missing 425 CorruptImageError the image file may be corrupt 430 FileOpenError the image file could not be opened 435 BlobError a binary large object could not be allocated 440 StreamError there was a problem reading or writing from a stream 445 CacheError pixels could not be saved to the pixel cache 485 XServerError an X resource is unavailable 490 RegistryError there was a problem getting or setting the registry 495 ConfigurationError there was a problem getting a configuration file $x = $image->Read('rose.png');
$x =~ /(\d+)/;
die "unable to continue" if ($1 == ResourceLimitError);
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Image manipulation software that works like magic.