Contents
Introduction Installation Overview Example Script Read or Write an Image Manipulate an Image Set an Image Attribute Get an Image Attribute Create an Image Montage Working with Blobs Miscellaneous Methods Handling Errors Copyright
Introduction
PerlMagick is an objected-oriented Perl interface to ImageMagick. Use the module to read, manipulate, or write an image or image sequence from within a Perl script. This makes it very suitable for Web CGI scripts. You must have ImageMagick 5.4.3 or above and Perl version 5.005_02 or greater installed on your system for either of these utilities to work. There are a number of useful scripts available to show you the value of PerlMagick. You can do Web based image manipulation and conversion with MagickStudio, or use L-systems to create images of plants using mathematical constructs, and finally navigate through collections of thumbnail images and select the image to view with the WebMagick Image Navigator. You can try PerlMagick from your Web browser at the ImageMagick Studio. Or, you can see examples of select PerlMagick functions. Back to Contents
Installation
> UNIX The 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 -
>         cd PerlMagick
> 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:
>         perl Makefile.PL
>         make
>         make install
> For Unix, you typically need to be `root` to install the software. There are ways around this. Consult the Perl manual pages for more information. Windows 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 install
> See the PerlMagick Windows HowTo page for further installation instructions. Running the Regression Tests To verify a correct installation, type
>         make test
> Use `nmake test` under Windows. There are a few demonstration scripts available to exercise many of the functions PerlMagick can perform. Type
>         cd demo
>         make
You are now ready to utilize the PerlMagick methods from within your Perl scripts. Back to Contents
Overview
> Any script that wants to use PerlMagick methods must first define the methods within its namespace and instantiate an image object. Do this with:
>         use Image::Magick;

>         $image=Image::Magick->new;
> The new() method takes the same parameters as SetAttribute . For example,
>         $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, use
>         undef $image->[x];
> The next section illustrates how to use various PerlMagick methods to manipulate an image sequence. 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,
>         $ENV{PATH}='/bin:/usr/bin:/usr/local/bin';
Back to Contents
Example Script
> Here is an example script to get you started:
>         #!/usr/local/bin/perl
>         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";
> The 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:
>         #!/usr/local/bin/perl
>         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');
> Suppose you want to start out with a 100 by 100 pixel white canvas with a red pixel in the center. Try
>         $image = Image::Magick->new;
>         $image->Set(size=>'100x100');
>         $image->ReadImage('xc:white');
>         $image->Set('pixel[49,49]'=>'red');
> Or suppose you want to convert your color image to grayscale:
>         $image->Quantize(colorspace=>'gray');
> Here we annotate an image with a Taipai TrueType font:
>         $text = 'Works like magick!';
>         $image->Annotate(font=>'kai.ttf', pointsize=>40, fill=>'green', text=>$text);
> Other clever things you can do with a PerlMagick objects include
>         $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
Back to Contents
Read or Write an Image
> Use the methods listed below to either read, write, or display an image or image sequence.
> 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;
>         $image->Write('png:-');
> To read an image in the GIF format from a PERL filehandle, use:
>         $image = Image::Magick->new;
>         open(IMAGE, 'image.gif');
>         $image->Read(file=>\*IMAGE);
>         close(IMAGE);
> To write an image in the PNG format to a PERL filehandle, use:
>         $filename = "image.png";
>         open(IMAGE, ">$filename");
>         $image->Write(file=>\*IMAGE, filename=>$filename);
>         close(IMAGE);
> 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,
>         image%03d.miff
converts files image000.miff, image001.miff, etc. You can optionally add Image to any method name. For example, ReadImage() is an alias for method Read(). Back to Contents
Manipulate an Image
> Once you create an image with, for example, method ReadImage() you may want to operate on it. Below is a list of all the image manipulations methods available to you with PerlMagick. There are examples of select PerlMagick methods. Here is an example call to an image manipulation method:
>         $image->Crop(geometry=>'100x100"+1"0+20');
>         $image->[x]->Frame("100x200");
> And here is a list of other image manipulation methods you can call:
> Image Manipulation Methods
> Method | Parameters | Description
> --- | --- | ---
> AdaptiveThreshold | geometry=>geometry, width=>integer, height=> integer, offset=>integer | local adaptive thresholding.
> 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
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=>{UTF-8} | 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
Compare | image=>image-handle | compare image to a reference 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, 'gamma'=>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
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, gray=>{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=>string | 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',
         points=>'20,20 100,100  40,40 200,200  60,60 300,300');

Is equivalent to

       $image->Draw(fill=>'red', primitive=>'@draw.txt');

Where `draw.txt` is a file on disk that contains this:

      rectangle 20, 20 100, 100
      rectangle 40, 40 200, 200
      rectangle 60, 60 300, 300

The 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:

        %b   file size
        %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 return

For example,

      text=>"%m:%f %wx%h"

produces an annotation of MIFF:bird.miff 512x480 for an image titled bird.miff and whose width is 512 and height is 480.

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.

Back to Contents

Set an Image Attribute

  Use method Set() to set an image attribute. For example,

>         $image->Set(dither=>'True');
>         $image->[$x]->Set(delay=>3);

> And here is a list of all the image attributes you can set:

> Image Attributes
> Attribute | Values | Description
> --- | --- | ---
> adjoin | {True, False} | join images into a single multi-image file
> antialias | {True, False} | remove pixel aliasing
> | authenticate | string | decrypt image with this password.
> 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
> 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
> compression | {None, BZip, Fax, Group4, JPEG, LosslessJPEG, LZW, RLE, Zip} | type of image compression
> debug | {No, Configure, Annotate, Render, Locale, Coder, X11, Cache, Blob, All} | display copious debugging information
> 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
> disk-limit | integer | set disk resource limit in megabytes
> dispose | {Undefined, None, Background, Previous} | GIF disposal method
> dither | {True, False} | apply error diffusion to the image
> display | string | specifies the X server to contact
> extract | geometry | extract area from image
> 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
> gamma | double | gamma level of the image
> 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
> map-limit | integer | set map resource limit in megabytes
> memory-limit | integer | set memory resource limit in megabytes
> 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
> 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.
> 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
> virtual-pixel | {Constant, Edge, Mirror, Tile} | the virtual pixel method
> 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.

Back to Contents

Get an Image Attribute

  Use method Get() to get an image attribute. For example,

>         ($a, $b, $c) = $image->Get('colorspace', 'magick', 'adjoin');
>         $width = $image->[3]->Get('columns');

> In addition to all the attributes listed in Set an Image Attribute , you can get these additional attributes:

> 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 | get the 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 with methods Compare() or Quantize()
> filesize | integer | number of bytes of the image on disk
> format | string | get the descriptive image format
> 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 with methods Compare() or Quantize()
> mean-error | double | the normalized mean error per pixel computed with methods Compare() or Quantize()
> 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.

Back to Contents

Create an Image Montage

  Use method Montage() to create a composite image by combining several separate images. The images are tiled on the composite image with the name of the image optionally appearing just below the individual tile. For example,

>         $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
> 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

  A blob contains data that directly represent a particular image format in memory instead of on disk. PerlMagick supports blobs in any of these image formats and provides methods to convert a blob to or from a particular image format.

> 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

> 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:

>         @blobs = $image->ImageToBlob();
>         open(DISPLAY,"| display -") || die;
>         binmode DISPLAY;
>         print DISPLAY $blobs[0];
>         close DISPLAY;

> Method BlobToImage() returns an image or image sequence converted from the supplied blob:

>         @blob=$db->GetImage();
>         $image=Image::Magick->new(magick=>'jpg');
>         $image->BlobToImage(@blob);

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Miscellaneous Methods

  The Append() method append a set of images. For example,

>         $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');
>         $image->Mogrify('crop', '340x256+0+0');

> Method MogrifyRegion() applies a transform to a region of the image. It is similar 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->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) =
>          $image->QueryFontMetrics(parameters);

> Where parameters is any parameter of the Annotate method. The return values are

> - character width
> - character height
> - ascender
> - descender
> - text width
> - text height
> - maximum horizontal advance

> Call 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.

>         @colors = $image->QueryColor();
>         ($red, $green, $blue, $opacity) = $image->QueryColor('cyan');
>         ($red, $green, $blue, $opacity) = $image->QueryColor('#716bae');

> QueryColorname() accepts a color value and returns its respective name or hex value;

>           $name = $image->QueryColorname('rgba(80,60,0,0)');

> 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.

>         @fonts = $image->QueryFont();
>         $weight = ($image->QueryFont('Helvetica'))[5];

> 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.

>         @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

  All PerlMagick methods return an undefined string context upon success. If any problems occur, the error is returned as a string with an embedded numeric status code. A status code less than 400 is a warning. This means that the operation did not complete but was recoverable to some degree. A numeric code greater or equal to 400 is an error and indicates the operation failed completely. Here is how errors are returned for the different methods:

- Methods which return a number (e.g. Read(), Write()):

        $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

- Methods which operate on an image (e.g. Resize(), Crop()):

        $x = $image->Crop(...);
        warn "$x" if "$x";      # print the error message
        $x =~ /(\d+)/;
        print $1;               # print the error number

- Methods which return images (Average(), Montage(), Clone()) should be checked for errors this way:

        $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:

>         Error 400: Memory allocation failed

> Below 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 occurred
> 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
> 350 | CoderWarning | there was a problem with an image coder
> 355 | ModuleWarning | there was a problem with an image module
> 360 | DrawWarning | a drawing operation failed
> 365 | ImageWarning | the operation could not complete due to an incompatible image
> 380 | XServerWarning | an X resource is unavailable
> 385 | MonitorWarning | there was a problem with prgress monitor
> 390 | RegistryWarning | there was a problem getting or setting the registry
> 395 | ConfigureWarning | 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 occurred
> 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
> 450 | CoderError | there was a problem with an image coder
> 455 | ModuleError | there was a problem with an image module
> 460 | DrawError | a drawing operation failed
> 465 | ImageError | the operation could not complete due to an incompatible image
> 480 | XServerError | an X resource is unavailable
> 480 | MonitorError | there was a progress monitor error
> 490 | RegistryError | there was a problem getting or setting the registry
> 495 | ConfigureError | there was a problem getting a configuration file

> The following illustrates how you can use a numeric status code:

>         $x = $image->Read('rose.png');
>         $x =~ /(\d+)/;
>         die "unable to continue" if ($1 == ResourceLimitError);

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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 ("PerlMagick"), to deal in PerlMagick without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of PerlMagick, and to permit persons to whom the PerlMagick 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 PerlMagick.

  The software is provided "as is", without warranty of any kind, express or implied, including but not limited to the warranties of merchantability, 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 PerlMagick or the use or other dealings in PerlMagick.

  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 PerlMagick without prior written authorization from the ImageMagick Studio.

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"Image manipulation software that works like magick"