From 895e9c3897d592b7df1c579a9522185c826c3a36 Mon Sep 17 00:00:00 2001 From: giraffedata Date: Sun, 22 Mar 2020 01:54:12 +0000 Subject: miscellaneous update git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@3769 9d0c8265-081b-0410-96cb-a4ca84ce46f8 --- pamcut.html | 23 +++++++++++------------ pamditherbw.html | 2 +- pnmshear.html | 8 +++++--- 3 files changed, 17 insertions(+), 16 deletions(-) diff --git a/pamcut.html b/pamcut.html index 9f0666c8..c0016b37 100644 --- a/pamcut.html +++ b/pamcut.html @@ -87,18 +87,17 @@ read, more expressive, and allow you to use defaults.

If you use both options and arguments, the two specifications get mixed in an unspecified way. -

To use arguments, specify all four of the left, -top, width, and height arguments. left -and top have the same effect as specifying them as the argument -of a -left or -top option, respectively. width -and height have the same effect as specifying them as the -argument of a -width or -height option, respectively, -where they are positive. Where they are not positive, they have the -same effect as specifying one less than the value as the argument to a --right or -bottom option, respectively. (E.g. -width = 0 makes the cut go all the way to the right edge). -Before July 2000, negative numbers were not allowed for width -and height. +

To use arguments, specify all four of the left, top, +width, and height arguments. left and top have +the same effect as specifying them as the argument of a -left or +-top option, respectively. width and height have the +same effect as specifying them as the argument of a -width or +-height option, respectively, where they are positive. Where they are +not positive, they have the same effect as specifying one less than the value +as the argument to a -right or -bottom option, respectively. +(E.g. width = 0 makes the cut go all the way to the right edge). +Before July 2000, negative numbers were not allowed for width and +height.

Input is from Standard Input if you don't specify the input file pnmfile. diff --git a/pamditherbw.html b/pamditherbw.html index c1f0bacf..5491a6f1 100644 --- a/pamditherbw.html +++ b/pamditherbw.html @@ -47,7 +47,7 @@ just takes the first channel of whatever you give it and treats it as if it represented gray levels).

The output is a PAM with tuple type BLACKANDWHITE. You can turn -this into a PBM (if you need to use it with an older program doesn't +this into a PBM (if you need to use it with an older program that doesn't understand PAM) with pamtopnm.

To do the opposite of dithering, you can usually just scale the image diff --git a/pnmshear.html b/pnmshear.html index 4ff36304..abdff36f 100644 --- a/pnmshear.html +++ b/pnmshear.html @@ -2,7 +2,7 @@ Pnmshear User Manual

pnmshear

-Updated: 27 November 2006 +Updated: 22 March 2020
Table Of Contents @@ -48,8 +48,10 @@ If the angle is negative, it shears the other way: +-------+ +-------+ -The angle should not get too close to 90 or -90, or the resulting -image will be unreasonably wide. +The angle should not get too close to 90 or -90, or the resulting image will +be unreasonably wide. In fact, if it gets too close, the width will be so +large that pnmshear cannot do computations in the word sizes it uses, +and the program detects this and fails.

pnmshear does the shearing by looping over the source pixels and distributing fractions to each of the destination pixels. This -- cgit 1.4.1