diff options
author | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2020-07-11 03:14:39 +0000 |
---|---|---|
committer | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2020-07-11 03:14:39 +0000 |
commit | a87703a515ec08a0637c2b3b3e6cd0ef1a7e78ff (patch) | |
tree | 0e462a89e51e65b0d293104f437aa371d8e56ee1 /pngtopam.html | |
parent | e4dbb262ce92440414dad7735f9b9264e47cffa0 (diff) | |
download | netpbm-mirror-a87703a515ec08a0637c2b3b3e6cd0ef1a7e78ff.tar.gz netpbm-mirror-a87703a515ec08a0637c2b3b3e6cd0ef1a7e78ff.tar.xz netpbm-mirror-a87703a515ec08a0637c2b3b3e6cd0ef1a7e78ff.zip |
cleanup
git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@3893 9d0c8265-081b-0410-96cb-a4ca84ce46f8
Diffstat (limited to 'pngtopam.html')
-rw-r--r-- | pngtopam.html | 148 |
1 files changed, 76 insertions, 72 deletions
diff --git a/pngtopam.html b/pngtopam.html index 47d82cd7..8bcd6739 100644 --- a/pngtopam.html +++ b/pngtopam.html @@ -1,33 +1,32 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN"> -<HTML><HEAD><TITLE>Pngtopam User Manual</TITLE></HEAD> -<BODY> -<H1>pngtopam</H1> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.3//EN"> +<html><head><title>Pngtopam User Manual</title></head> +<body> +<h1>pngtopam</h1> Updated: 22 July 2008 -<BR> -<A HREF="#index">Table Of Contents</A> - -<H2>NAME</H2> +<br> +<a href="#index">Table Of Contents</a> +<h2>NAME</h2> pngtopam - convert a PNG image into a Netpbm image -<H2 id="synopsis">SYNOPSIS</H2> +<h2 id="synopsis">SYNOPSIS</h2> -<B>pngtopam</B> +<b>pngtopam</b> [<b>-verbose</b>] [<b>-alphapam</b> | <b>-alpha</b> | <b>-mix</b>] [<b>-background</b>=<i>color</i>] -<BR> +<br> [<b>-gamma</b>=<i>value</i>] [<b>-text</b>=<i>filename</i>] [<b>-time</b>] -[<B>-byrow</B>] -[<I>pngfile</I>] +[<b>-byrow</b>] +[<i>pngfile</i>] -<P>Minimum unique abbreviation of option is acceptable. You may use double +<p>Minimum unique abbreviation of option is acceptable. You may use double hyphens instead of single hyphen to denote options. You may use white space in place of the equals sign to separate an option name from its value. -<H2 id="description">DESCRIPTION</H2> +<h2 id="description">DESCRIPTION</h2> <p>This program is part of <a href="index.html">Netpbm</a>. @@ -47,20 +46,25 @@ transparency information in a PAM file, as you might generate with <b>pngtopam features, but probably not ones that matter in the modern world. -<H2 id="options">OPTIONS</H2> +<h2 id="options">OPTIONS</h2> + +<p>In addition to the options common to all programs based on libnetpbm +(most notably <b>-quiet</b>, see <a href="index.html#commonoptions"> +Common Options</a>), <b>pngtopam</b> recognizes the following +command line options: -<DL COMPACT> -<DT><B>-verbose</B> +<dl compact> +<dt><b>-verbose</b> -<DD>Display various information about the input PNG image and the +<dd>Display various information about the input PNG image and the conversion process. <p>If you want even more information about the PNG image, use <b>pngcheck</b> (not part of Netpbm). -<DT><B>-alphapam</B> +<dt><b>-alphapam</b> -<DD>Produce a single output image containing the main image (foreground) +<dd>Produce a single output image containing the main image (foreground) and the transparency channel or transparency mask. This image is in the PAM format with tuple type of either GRAYSCALE_ALPHA (which has a depth of 2 channels) or RGB_ALPHA (which has a depth of 4 channels). @@ -69,11 +73,11 @@ format with tuple type of either GRAYSCALE_ALPHA (which has a depth of <b>-mix</b>. With none of them, <b>pngtopam</b> produces an image of the foreground of the input image and discards transparency information. -<P>This option was new in Netpbm 10.44 (September 2008). +<p>This option was new in Netpbm 10.44 (September 2008). -<DT><B>-alpha</B> +<dt><b>-alpha</b> -<DD>Output the transparency channel or transparency mask of the image. The +<dd>Output the transparency channel or transparency mask of the image. The result is either a PBM file or a PGM file, depending on whether different levels of transparency appear. @@ -83,9 +87,9 @@ different levels of transparency appear. <b>-mix</b>. With none of them, <b>pngtopam</b> produces an image of the foreground of the input image and discards transparency information. -<DT><B>-mix</B> +<dt><b>-mix</b> -<DD>Compose the image with the transparency or transparency mask against a +<dd>Compose the image with the transparency or transparency mask against a background. The background color is determined by the bKGD chunk in the PNG, except that you can override it with <b>-background</b>. If the PNG has no bKGD chunk and you don't specify <b>-background</b>, @@ -95,13 +99,13 @@ the background color is white. <b>-mix</b>. With none of them, <b>pngtopam</b> produces an image of the foreground of the input image and discards transparency information. -<DT><B>-background=</b><i>color</i> +<dt><b>-background=</b><i>color</i> -<DD> +<dd> This option specifies the background color with which to mix the image when you specify <b>-mix</b>. -<P><i>color</i> is as described for the <a +<p><i>color</i> is as described for the <a href="libnetpbm_image.html#colorname">argument of the <b>pnm_parsecolor()</b> library routine</a>. @@ -122,7 +126,7 @@ white. caused a usability problem). -<DT><B>-gamma=</b><i>value</i> +<dt><b>-gamma=</b><i>value</i> <dd>This option causes <b>pngtopam</b> to respect the image gamma information in the PNG file (from the gAMA chunk). Probably by historical accident, @@ -171,42 +175,42 @@ correction, those three shades are indistinguishable, so <b>pngtopam</b> considers pixels of all three shades to be transparent. -<DT><B>-text=</b><i>file</i> +<dt><b>-text=</b><i>file</i> -<DD>Writes the tEXt and zTXt chunks to a file, in a format as +<dd>Writes the tEXt and zTXt chunks to a file, in a format as described in the <b>pnmtopng</b> user manual. These chunks contain text comments or annotations. -<DT><B>-time</B> +<dt><b>-time</b> -<DD>Prints the tIME chunk to stderr. +<dd>Prints the tIME chunk to stderr. -<DT><B>-byrow</B> +<dt><b>-byrow</b> -<DD>This option can make <b>pngtopam</b> run faster or in environments +<dd>This option can make <b>pngtopam</b> run faster or in environments where it would otherwise fail. -<P><B>pngtopam</B> has two ways to do the conversion from PNG to PAM, using +<p><b>pngtopam</b> has two ways to do the conversion from PNG to PAM, using respectively two facilities of the PNG library: -<DL> +<dl> -<DT>Whole Image +<dt>Whole Image -<DD>Decode the entire image into memory at once, using +<dd>Decode the entire image into memory at once, using <b>png_read_image()</b>, then convert to PAM and output row by row. -<DT>Row By Row -<DD>Read, convert, and output one row at a time using <b>png_read_row()</b>. +<dt>Row By Row +<dd>Read, convert, and output one row at a time using <b>png_read_row()</b>. -</DL> +</dl> -<P>Whole Image is generally preferable because the PNG library does more of +<p>Whole Image is generally preferable because the PNG library does more of the work, which means it understands more of the PNG format possibilities now and in the future. Also, if the PNG is interlaced, <b>pngtopam</b> does not know how to assemble the rows in the right order. -<P>Row By Row uses far less memory, which means with large images, it +<p>Row By Row uses far less memory, which means with large images, it can run in environments where Whole Image cannot and may also run faster. And because Netpbm code does more of the work, it's possible that it can be more flexible or at least give better diagnostic @@ -215,8 +219,8 @@ information if there's something wrong with the PNG. <p>The Netpbm native code may do something correctly that the PNG library does incorrectly, or vice versa. -<P>In Netpbm, we stress function over performance, so by default -<B>pngtopam</B> uses Whole Image. You can select Row By Row with +<p>In Netpbm, we stress function over performance, so by default +<b>pngtopam</b> uses Whole Image. You can select Row By Row with <b>-byrow</b> if you want the speed or resource requirement improvement. <p><b>-byrow</b> was new in Netpbm 10.54 (March 2011). @@ -237,21 +241,21 @@ is oriented that way. considerable amount of processing for <b>tifftopnm</b> to convert it to Netpbm format. -</DL> +</dl> -<H2 id="seealso">SEE ALSO</H2> +<h2 id="seealso">SEE ALSO</h2> -<A HREF="pnmtopng.html">pamtopng</A>, -<A HREF="pnmtopng.html">pnmtopng</A>, -<A HREF="pngtopnm.html">pngtopnm</A>, +<a href="pnmtopng.html">pamtopng</a>, +<a href="pnmtopng.html">pnmtopng</a>, +<a href="pngtopnm.html">pngtopnm</a>, <b>ptot</b>, -<A HREF="pnmgamma.html">pnmgamma</A>, -<A HREF="pnm.html">pnm</A> +<a href="pnmgamma.html">pnmgamma</a>, +<a href="pnm.html">pnm</a> <p>For information on the PNG format, see <a href="http://schaik.com/png">http://schaik.com/png</a>. -<H2 id="note">NOTE</H2> +<h2 id="note">NOTE</h2> <p>A PNG image contains a lot of information that can't be represented in Netpbm formats. Therefore, you lose information when you convert to @@ -259,12 +263,12 @@ another format with "pngtopam | pnmtoxxx". If there is a specialized converter that converts directly to the other format, e.g. <b>ptot</b> to convert from PNG to TIFF, you'll get better results using that. -<H2 id="limitations">LIMITATIONS</H2> +<h2 id="limitations">LIMITATIONS</h2> <p>There could be an option to include PNG comment chunks in the output image as PNM comments instead of putting them in a separate file. -<P>The program could be much faster, with a bit of code optimizing. +<p>The program could be much faster, with a bit of code optimizing. As with any Netpbm program, speed always takes a back seat to quick present and future development. @@ -289,21 +293,21 @@ simpler reference applications by Alexander Lehmann <b>pnmtopng</b> package, most of it just to improve maintainability. -<H2 id="authors">AUTHORS</H2> +<h2 id="authors">AUTHORS</h2> Copyright (C) 1995-1997 by Alexander Lehmann and Willem van Schaik. -<HR> -<H2 id="index">Table Of Contents</H2> -<UL> -<LI><A HREF="#synopsis">SYNOPSIS</A> -<LI><A HREF="#description">DESCRIPTION</A> -<LI><A HREF="#options">OPTIONS</A> -<LI><A HREF="#seealso">SEE ALSO</A> -<LI><A HREF="#note">NOTE</A> -<LI><A HREF="#limitations">LIMITATIONS</A> -<LI><A HREF="#history">HISTORY</A> -<LI><A HREF="#authors">AUTHORS</A> -</UL> -</BODY> -</HTML> +<hr> +<h2 id="index">Table Of Contents</h2> +<ul> +<li><a href="#synopsis">SYNOPSIS</a> +<li><a href="#description">DESCRIPTION</a> +<li><a href="#options">OPTIONS</a> +<li><a href="#seealso">SEE ALSO</a> +<li><a href="#note">NOTE</a> +<li><a href="#limitations">LIMITATIONS</a> +<li><a href="#history">HISTORY</a> +<li><a href="#authors">AUTHORS</a> +</ul> +</body> +</html> |