Pamsharpmap User Manual
Pamsharpmap User Manual
NAMESYNOPSIS
DESCRIPTION
SEE ALSO
HISTORY
NAME
pamsharpmap - create map of sharpness in a PNM/PAM image
SYNOPSIS
pamsharpmap [imagefile]
DESCRIPTION
This program is part of Netpbm(1)
pamsharpmap reads a Netpbm image (PNM or PAM) and produces an image that shows how sharp it is at each location.
Sharpness is a measure of how suddenly (in space) colors change in the image. pamsharpmap computes the sharpness of each component color (R, G, B) separately and produces a pixel whose intensity of each component color is directly proportional to the sharpness of that component color at the same location in the input image. Thus, at a point where the image is very sharp in its red and green components, but dull in its blue component, you will see a yellow pixel in the output.
pamsharpmap computes sharpness at a point simply as the average difference in intensity between the pixel at that point and the 8 pixels surrounding it.
At the edges of the image, where there are not 8 pixels surrounding a pixel, pamsharpmap assumes the image is extended with a black border.
pamsharpmap assumes that the image is a PNM or PNM equivalent PAM. If it isn’t, the results are not necessarily meaningful.
The output image is the same dimensions, depth, and tuple type as the input, and has maxval 255.
SEE ALSO
pamsharpness(1) , pammasksharpen(1) , pamedge(1) , pam(5) , pnm(5)
HISTORY
pamsharpmap was added to Netpbm in Release 10.21 (March 2004). Bryan Henderson derived it from the program pnmsharp by B.W. van Schooten and distributed as part of the Photopnmtools package.
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
