GIF(3pm) User Contributed Perl Documentation GIF(3pm)NAME
Imager::File::GIF - read and write GIF files
SYNOPSIS
use Imager;
my $img = Imager->new;
$img->read(file=>"foo.gif")
or die $img->errstr;
$img->write(file => "foo.gif")
or die $img->errstr;
DESCRIPTION
Imager's GIF support is documented in Imager::Files.
AUTHOR
Tony Cook <tonyc@cpan.org>
SEE ALSO
Imager, Imager::Files.
perl v5.14.2 2012-03-18 GIF(3pm)
Check Out this Related Man Page
Imager::Security(3pm) User Contributed Perl Documentation Imager::Security(3pm)NAME
Imager::Security - brief notes on security and image processing
SYNOPSIS
# keep abreast of security updates
apt-get update && apt-get upgrade
yum upgrade
pkgin update && pkgin upgrade
# or local equivalent
# limit memory use
use Imager;
# only images that use up to 10MB
Imager->set_file_limits(bytes => 10_000_000);
DESCRIPTION
There's two basic security considerations when dealing with images from an unknown source:
o keeping your libraries up to date
o limiting the amount of memory used to store images
Keeping libraries up to date
Image file format libraries such as "libpng" or "libtiff" have relatively frequent security updates, keeping your libraries up to date is
basic security.
If you're using user supplied fonts, you will need to keep your font libraries up to date too.
Limiting memory used
With compression, and especially with pointer formats like TIFF, it's possible to store very large images in a relatively small file.
If you're receiving image data from an untrusted source you should limit the amount of memory that Imager can allocate for a read in image
file using the "set_file_limits()" method.
Imager->set_file_limits(bytes => 10_000_000);
You may also want to limit the maximum width and height of images read from files:
Imager->set_file_limits(width => 10_000, height => 10_000,
bytes => 10_000_000);
This has no effect on images created without a file:
# succeeds
my $image = Imager->new(xsize => 10_001, ysize => 10_001);
You can reset to the defaults with:
Imager->set_file_limits(reset => 1);
AUTHOR
Tony Cook <tonyc@cpan.org>
perl v5.14.2 2012-06-04 Imager::Security(3pm)
I have a huge matrix file containing some 1.5 million rows and 6000 columns. The matrix looks something like this:
1 2 3
4 5 6
7 8 9
3 4 5
I want to add all the numbers in the columns of this matrix and display the result to my stdout. This means that the numbers in the first column are:
... (2 Replies)
Hi,
Just trying to get to grips with sed and awk for some reporting for work and I need some assistance:
I have a file that lists policy names on the first line and then on the second line whether the policy is active or not.
Policy Name: Policy1
Active: yes
Policy... (8 Replies)
version info :
vi availabe with RHEL 5.4
I have a text file with 10,000 lines. I want to copy lines from 5000th line to 7000th and redirect to a file. Any idea how I can do this?
Note:
The above scenario is just an example. In my actual requirement, the file has 14 million lines and I want... (9 Replies)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello,
I couldn't find an actual introduction thread, so I decided to just put this here.
I go by d0wngrade online. I have been programming in multiple languages for about 15+ years. I started with standard web design languages like HTML and CSS, but I then advanced from design to development... (2 Replies)
Hi guys...
The first active code line in AudioScope.sh is set -u .
This causes a complete exit if a variable is used/found but has not been allocated at the start of the program.
However, apart from writing code to do the task, is there a switch to to check which variables have been... (17 Replies)
Hi.
In thread https://www.unix.com/shell-programming-and-scripting/267833-grouping-counting.html rovf and I had a mini-discussion on grep and awk.
Here is a demo script that compares the awk and grep approaches for this single problem:
#!/usr/bin/env bash
# @(#) s2 Demonstrate group... (1 Reply)
Hello,
I have to fish out some specific columns from a file based on the header value. I have the list of columns I need in a different file. I thought I could read in the list of headers I need,
# file with header names of required columns in required order
headers_file=$2
# read contents... (11 Replies)
For those interested in installing dash shell on OSX Lion to help test POSIX compliancy of shell scripts, it is quite easy. I did it like this:
If you don't have gcc on your system:
0. Download and install the Command Line Tools for Xcode package from Sign In - Apple *
1. Download the dash... (2 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
I have data of an excel files as given below,
file1
org1_1 1 1 2.5 100
org1_2 1 2 5.5 98
org1_3 1 3 7.2 88
file2
org2_1 1 1 2.5 100
org2_2 1 2 5.5 56
org2_3 1 3 7.2 70
I have multiple excel files as above shown.
I have to copy column 1, column 4 and paste into a new excel file as... (26 Replies)
Dear All,
Taking a break from Vue.js coding for the site, SEO and YT videos; and hopefully addressing some well deserved criticism from some here that I have been too focused on the visual aspects of the forums versus the substance and the community....
While the "current generation... (9 Replies)
Hi all...
Well guys and gals, I jumped in at the deep end and found things that PERL cannot do by default.
Many tricky terminal escape codes are not catered for so I had to create workarounds.
One thing I searched for was this:
Passing perl variable to shell command
AND, @Neo this was... (15 Replies)