This library contains four PostgreSQL C functions for calculating color difference in L*a*b* color space, which is designed for evaluating perceptual similarity.
To build colors:
make
make install
make installcheck
If you encounter an error such as:
"Makefile", line 8: Need an operator
You need to use GNU make, which may well be installed on your system as
gmake:
gmake
gmake install
gmake installcheck
If you encounter an error such as:
make: pg_config: Command not found
Be sure that you have pg_config installed and in your path. If you used a
package management system such as RPM to install PostgreSQL, be sure that the
-devel package is also installed. If necessary tell the build process where
to find it:
env PG_CONFIG=/path/to/pg_config make && make installcheck && make install
If you encounter an error such as:
ERROR: must be owner of database regression
You need to run the test suite using a super user, such as the default "postgres" super user:
make installcheck PGUSER=postgres
Once colors is installed, you can add it to a database. If you're running PostgreSQL 9.1.0 or greater, it's a simple as connecting to a database as a super user and running:
CREATE EXTENSION colors;
For versions of PostgreSQL less than 9.1.0, you'll need to run the installation script:
psql -d mydb -f /path/to/pgsql/share/contrib/colors.sql
If you want to install colors and all of its supporting objects into a
specific schema, use the PGOPTIONS environment variable to specify the
schema, like so:
PGOPTIONS=--search_path=extensions psql -d mydb -f colors.sql
The colors data type has no dependencies other than PostgreSQL and PL/pgSQL.
Copyright (c) 2010-2014 Gasper Zejn.
This module is free software; you can redistribute it and/or modify it under the PostgreSQL License.
Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies.
In no event shall Gasper Zejn be liable to any party for direct, indirect, special, incidental, or consequential damages, including lost profits, arising out of the use of this software and its documentation, even if Gasper Zejn has been advised of the possibility of such damage.
Gasper Zejn specifically disclaims any warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The software provided hereunder is on an "as is" basis, and Gasper Zejn has no obligations to provide maintenance, support, updates, enhancements, or modifications.