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diff --git a/spamassassin/fuzzyocr/INSTALL b/spamassassin/fuzzyocr/INSTALL new file mode 100644 index 0000000..672e37d --- /dev/null +++ b/spamassassin/fuzzyocr/INSTALL @@ -0,0 +1,119 @@ +Installation manual for FuzzyOcr 2.3: + +1. Dependencies you require for this plugin to work + + Before starting, also make sure to read the OS/distribution specific notes at the end of this section. + + 1.1 Spamassassin 3.x + + This plugin requires Spamassassin 3.x. Using it on version 2.x is not supported and might fail. + At least one function in this plugin requires Spamassassin 3.1.4, if you do not have this version, + don't forget to set the "focr_pre314" option in the FuzzyOcr.cf file. + + 1.2 NetPBM tools + + Install the NetPBM tools (http://netpbm.sourceforge.net/). If you don't install the binaries in /usr/bin, + please make sure to adjust the FuzzyOcr.cf to point to the correct binaries. + + 1.3 ImageMagick + + At least one feature requires the convert binary from imagemagick (http://www.imagemagick.org/). + Again, make sure the configuration file points to the convert binary, if not placed in /usr/bin. + + 1.4 Giflib (also known as libungif) + + Several tools from this package are required, see (http://sourceforge.net/projects/libungif). + Attention: the giftext binary from this package has a bug which can cause segfaults. + On the download page, a source patch is provided which fixes this. + + 1.5 Gocr + For OCR recognition, gocr (http://jocr.sourceforge.net/) must be installed. + Attention: the gocr binary has a bug which can cause segfaults with specific images. + On the download page, a source patch is provided which fixes this. + + 1.6 Perl modules: + These perl modules are required: + Digest::MD5 + String::Approx + + Notes for Fedora Core 5 (or higher) users: The package libungif-utils provides the necessary libungif binaries. + Notes for other Redhat/FC users: The packages libungif and libungif-progs should be installed. + Notes for Debian users: The package libungif-bin provides the necessary libungif binaries. + + Notes for Slackware users: I have no clue about this distro, but Andy Lyttle sent me a mail about it: + + "Slackware doesn't currently have a libungif-utils/progs/bin package, and the libungif package does not include the binaries such as giffix. So, you have to hack it a bit. + + 1. Download (or copy from CD) the /source/l/libungif directory, don't untar anything + 2. Edit the libungif.SlackBuild and comment out this line: + # I don't believe we need all this slop. Correct me if I'm wrong. + rm -rf $PKG/usr/bin + 3. Run "sh libungif.SlackBuild" + 4. Uninstall the libungif package, if it's already installed + 5. Look in /tmp, and install the new libungif package there" + + Notes for Gentoo users: All dependencies except the perl modules can be installed via portage. But because of the bugs in giftext and gocr, + you might need to write an ebuild which uses the two patches found on my download page. The perl modules can easily be + installed with gcpan. + + +2. Installing the plugin: + + 2.1. Installing the required files + + Put the FuzzyOcr.cf and the FuzzyOcr.pm files into /etc/mail/spamassassin. + The FuzzyOcr.cf file already contains a line to load the plugin, if you want to put the .pm file in a different location, + change this line accordingly. + Create a wordlist file, a sample wordlist is shipped with this release, and put it also in /etc/mail/spamassassin. + + 2.2 Necessary configuration + + Open the FuzzyOcr.cf. Make sure that you specify a writable file as a logfile, or a directory where the plugin can write to, + so it can create the logfile itself. Also make sure that you specify a correct file as global wordlist. + With these two adjustments, FuzzyOcr is already to work. + + 3. Further adjustments + + 3.1. Enabling the image hash database + + Set focr_enable_image_hashing to 1 in the config file, and make sure that focr_digest_db points to a writable file/directory. + You can also create this file yourself if you like. By default, all images recognized as spam, are added + to this database automatically. The score is saved as well and reused later again. + + 3.2 Tweaking Scansets + + Everyone gets different image spam, and most times, one method to scan is not successful with all types of spam you get. + That's where the focr_scansets setting can help you. This setting takes a comma seperated list of scansets. + Each scanset starts with the name of a program, followed by either other programs connected with pipes, or nothing anymore. + The only important thing is that input for this "program chain" is a picture in the PNM format, and the output is ASCII text. + + An example might clarify this: + focr_scanset gocr -i - + + This will do a single scan with gocr default settings. + + focr_scanset pnminvert | gocr -i - + + This will use pnminvert on the image and then do the scan. + + focr_scanset gocr -i -, gocr -l 180 -i - + + This will do 2 scans, one with the default settings, and the second one with a modified -l value. + + You are now free to select which scansets get you the most spam, but don't pick too many, as this will also use more resources. + + Here are some hints: -pnminvert or pnmquant are useful with white text or text with many colors + -If you get images which are littered with small dots/lines, try -d 2 as an argument to gocr + -The -l setting often helps, try values like 180, 140, or 100 + + Two syntax remarks: -Instead of writing "gocr", write "$gocr" as this will be replaced with the correct path to your gocr binary. + -If you invoke custom binaries (like pnminvert for example), you can redirect the stderr output by using: + "pnminvert 2>>$errfile" + If the scanset fails then, and debug logging is enabled, you will see this stderr output in the logfile :) + + I know this seems confusing for some, but if this is unclear somehow, feel free to write an email to the list. + + +And now, where it gets most thrilling... + +To be continued... |