NAME

Imager - Perl extension for Generating 24 bit Images

SYNOPSIS

# Thumbnail example

#!/usr/bin/perl -w
use strict;
use Imager;

die "Usage: thumbmake.pl filename\n" if !-f $ARGV[0];
my $file = shift;

my $format;

my $img = Imager->new();
# see Imager::Files for information on the read() method
$img->read(file=>$file) or die $img->errstr();

$file =~ s/\.[^.]*$//;

# Create smaller version
# documented in Imager::Transformations
my $thumb = $img->scale(scalefactor=>.3);

# Autostretch individual channels
$thumb->filter(type=>'autolevels');

# try to save in one of these formats
SAVE:

for $format ( qw( png gif jpg tiff ppm ) ) {
  # Check if given format is supported
  if ($Imager::formats{$format}) {
    $file.="_low.$format";
    print "Storing image as: $file\n";
    # documented in Imager::Files
    $thumb->write(file=>$file) or
      die $thumb->errstr;
    last SAVE;
  }
}

DESCRIPTION

Imager is a module for creating and altering images. It can read and write various image formats, draw primitive shapes like lines,and polygons, blend multiple images together in various ways, scale, crop, render text and more.

Overview of documentation

  • Imager - This document - Synopsis Example, Table of Contents and Overview.

  • Imager::Tutorial - a brief introduction to Imager.

  • Imager::Cookbook - how to do various things with Imager.

  • Imager::ImageTypes - Basics of constructing image objects with new(): Direct type/virtual images, RGB(A)/paletted images, 8/16/double bits/channel, color maps, channel masks, image tags, color quantization. Also discusses basic image information methods.

  • Imager::Files - IO interaction, reading/writing images, format specific tags.

  • Imager::Draw - Drawing Primitives, lines, boxes, circles, arcs, flood fill.

  • Imager::Color - Color specification.

  • Imager::Fill - Fill pattern specification.

  • Imager::Font - General font rendering, bounding boxes and font metrics.

  • Imager::Transformations - Copying, scaling, cropping, flipping, blending, pasting, convert and map.

  • Imager::Engines - Programmable transformations through transform(), transform2() and matrix_transform().

  • Imager::Filters - Filters, sharpen, blur, noise, convolve etc. and filter plugins.

  • Imager::Expr - Expressions for evaluation engine used by transform2().

  • Imager::Matrix2d - Helper class for affine transformations.

  • Imager::Fountain - Helper for making gradient profiles.

  • Imager::API - using Imager's C API

  • Imager::APIRef - API function reference

  • Imager::Inline - using Imager's C API from Inline::C

  • Imager::ExtUtils - tools to get access to Imager's C API.

Basic Overview

An Image object is created with $img = Imager->new(). Examples:

$img=Imager->new();                         # create empty image
$img->read(file=>'lena.png',type=>'png') or # read image from file
   die $img->errstr();                      # give an explanation
                                            # if something failed

or if you want to create an empty image:

$img=Imager->new(xsize=>400,ysize=>300,channels=>4);

This example creates a completely black image of width 400 and height 300 and 4 channels.

When an operation fails which can be directly associated with an image the error message is stored can be retrieved with $img->errstr().

In cases where no image object is associated with an operation $Imager::ERRSTR is used to report errors not directly associated with an image object. You can also call Imager-errstr> to get this value.

The Imager->new method is described in detail in Imager::ImageTypes.

METHOD INDEX

Where to find information on methods for Imager class objects.

addcolors() - "addcolors" in Imager::ImageTypes

addtag() - "addtag" in Imager::ImageTypes - add image tags

arc() - "arc" in Imager::Draw

align_string() - "align_string" in Imager::Draw

bits() - "bits" in Imager::ImageTypes - number of bits per sample for the image

box() - "box" in Imager::Draw

circle() - "circle" in Imager::Draw

colorcount() - "colorcount" in Imager::Draw

convert() - "Color transformations" in Imager::Transformations - transform the color space

copy() - "copy" in Imager::Transformations

crop() - "crop" in Imager::Transformations - extract part of an image

deltag() - "deltag" in Imager::ImageTypes - delete image tags

difference() - "Image Difference" in Imager::Filters

errstr() - "Basic Overview"

filter() - Imager::Filters

findcolor() - "findcolor" in Imager::ImageTypes - search the image palette, if it has one

flip() - "flip" in Imager::Transformations

flood_fill() - "flood_fill" in Imager::Draw

getchannels() - "getchannels" in Imager::ImageTypes

getcolorcount() - "getcolorcount" in Imager::ImageTypes

getcolors() - "getcolors" in Imager::ImageTypes - get colors from the image palette, if it has one

get_file_limits() - "Limiting the sizes of images you read" in Imager::Files

getheight() - "getwidth" in Imager::ImageTypes

getpixel() - "getpixel" in Imager::Draw

getsamples() - "getsamples" in Imager::Draw

getscanline() - "getscanline" in Imager::Draw

getwidth() - "getwidth" in Imager::ImageTypes

img_set() - "img_set" in Imager::ImageTypes

line() - "line" in Imager::Draw

map() - "Color Mappings" in Imager::Transformations - remap color channel values

masked() - "masked" in Imager::ImageTypes - make a masked image

matrix_transform() - "matrix_transform" in Imager::Engines

maxcolors() - "maxcolors" in Imager::ImageTypes

new() - "new" in Imager::ImageTypes

open() - Imager::Files - an alias for read()

paste() - "paste" in Imager::Transformations - draw an image onto an image

polygon() - "polygon" in Imager::Draw

polyline() - "polyline" in Imager::Draw

read() - Imager::Files - read a single image from an image file

read_multi() - Imager::Files - read multiple images from an image file

rotate() - "rotate" in Imager::Transformations

rubthrough() - "rubthrough" in Imager::Transformations - draw an image onto an image and use the alpha channel

scale() - "scale" in Imager::Transformations

scaleX() - "scaleX" in Imager::Transformations

scaleY() - "scaleY" in Imager::Transformations

setcolors() - "setcolors" in Imager::ImageTypes - set palette colors in a paletted image

setpixel() - "setpixel" in Imager::Draw

setscanline() - "setscanline" in Imager::Draw

settag() - "settag" in Imager::ImageTypes

set_file_limits() - "Limiting the sizes of images you read" in Imager::Files

string() - "string" in Imager::Draw - draw text on an image

tags() - "tags" in Imager::ImageTypes - fetch image tags

to_paletted() - "to_paletted" in Imager::ImageTypes

to_rgb8() - "to_rgb8" in Imager::ImageTypes

transform() - "transform" in Imager::Engines

transform2() - "transform2" in Imager::Engines

type() - "type" in Imager::ImageTypes - type of image (direct vs paletted)

virtual() - "virtual" in Imager::ImageTypes - whether the image has it's own data

write() - Imager::Files - write an image to a file

write_multi() - Imager::Files - write multiple image to an image file.

CONCEPT INDEX

animated GIF - "Writing an animated GIF" in Imager::File

aspect ratio - "i_xres" in Imager::ImageTypes, "i_yres" in Imager::ImageTypes, "i_aspect_only" in Imager::ImageTypes

blend - alpha blending one image onto another "rubthrough" in Imager::Transformations

blur - "guassian" in Imager::Filters, "conv" in Imager::Filters

boxes, drawing - "box" in Imager::Draw

changes between image - "Image Difference" in Imager::Filter

color - Imager::Color

color names - Imager::Color, Imager::Color::Table

combine modes - "combine" in Imager::Fill

compare images - "Image Difference" in Imager::Filter

contrast - "contrast" in Imager::Filter, "autolevels" in Imager::Filter

convolution - "conv" in Imager::Filter

cropping - "crop" in Imager::Transformations

diff images - "Image Difference" in Imager::Filter

dpi - "i_xres" in Imager::ImageTypes

drawing boxes - "box" in Imager::Draw

drawing lines - "line" in Imager::Draw

drawing text - "string" in Imager::Font, "align" in Imager::Font

error message - "Basic Overview"

files, font - Imager::Font

files, image - Imager::Files

filling, types of fill - Imager::Fill

filling, boxes - "box" in Imager::Draw

filling, flood fill - "flood_fill" in Imager::Draw

flood fill - "flood_fill" in Imager::Draw

fonts - Imager::Font

fonts, drawing with - "string" in Imager::Font, "align" in Imager::Font, Imager::Font::Wrap

fonts, metrics - "bounding_box" in Imager::Font, Imager::Font::BBox

fonts, multiple master - "MULTIPLE MASTER FONTS" in Imager::Font

fountain fill - "Fountain fills" in Imager::Fill, "fountain" in Imager::Filters, Imager::Fountain, "gradgen" in Imager::Filters

GIF files - "GIF" in Imager::Files

GIF files, animated - "Writing an animated GIF" in Imager::File

gradient fill - "Fountain fills" in Imager::Fill, "fountain" in Imager::Filters, Imager::Fountain, "gradgen" in Imager::Filters

guassian blur - "guassian" in Imager::Filter

hatch fills - "Hatched fills" in Imager::Fill

invert image - "hardinvert" in Imager::Filter

JPEG - "JPEG" in Imager::Files

limiting image sizes - "Limiting the sizes of images you read" in Imager::Files

lines, drawing - "line" in Imager::Draw

matrix - Imager::Matrix2d, "Matrix Transformations" in Imager::Transformations, "transform" in Imager::Font

metadata, image - "Tags" in Imager::ImageTypes

mosaic - "mosaic" in Imager::Filter

noise, filter - "noise" in Imager::Filter

noise, rendered - "turbnoise" in Imager::Filter, "radnoise" in Imager::Filter

paste - "paste" in Imager::Transformations, "rubthrough" in Imager::Transformations

pseudo-color image - "to_paletted" in Imager::ImageTypes, "new" in Imager::ImageTypes

posterize - "postlevels" in Imager::Filter

png files - Imager::Files, "PNG" in Imager::Files

pnm - "PNM (Portable aNy Map)" in Imager::Files

rectangles, drawing - "box" in Imager::Draw

resizing an image - "scale" in Imager::Transformations, "crop" in Imager::Transformations

saving an image - Imager::Files

scaling - "scale" in Imager::Transformations

sharpen - "unsharpmask" in Imager::Filters, "conv" in Imager::Filters

size, image - "getwidth" in Imager::ImageTypes, "getheight" in Imager::ImageTypes

size, text - "bounding_box" in Imager::Font

tags, image metadata - "Tags" in Imager::ImageTypes

text, drawing - "string" in Imager::Draw, "align_string" in Imager::Draw, Imager::Font::Wrap

text, wrapping text in an area - Imager::Font::Wrap

text, measuring - "bounding_box" in Imager::Font, Imager::Font::BBox

tiles, color - "mosaic" in Imager::Filter

unsharp mask - "unsharpmask" in Imager::Filter

watermark - "watermark" in Imager::Filter

writing an image to a file - Imager::Files

SUPPORT

You can ask for help, report bugs or express your undying love for Imager on the Imager-devel mailing list.

To subscribe send a message with subscribe in the body to:

imager-devel+request@molar.is

or use the form at:

where you can also find the mailing list archive.

If you're into IRC, you can typically find the developers in #Imager on irc.perl.org. As with any IRC channel, the participants could be occupied or asleep, so please be patient.

You can report bugs by pointing your browser at:

Please remember to include the versions of Imager, perl, supporting libraries, and any relevant code. If you have specific images that cause the problems, please include those too.

BUGS

Bugs are listed individually for relevant pod pages.

AUTHOR

Arnar M. Hrafnkelsson and Tony Cook (tony@imager.perl.org) among others. See the README for a complete list.

SEE ALSO

perl(1), Imager::ImageTypes(3), Imager::Files(3), Imager::Draw(3), Imager::Color(3), Imager::Fill(3), Imager::Font(3), Imager::Transformations(3), Imager::Engines(3), Imager::Filters(3), Imager::Expr(3), Imager::Matrix2d(3), Imager::Fountain(3)

http://imager.perl.org/

Affix::Infix2Postfix(3), Parse::RecDescent(3)

Other perl imaging modules include:

GD(3), Image::Magick(3), Graphics::Magick(3).