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diff --git a/ppmsvgalib.html b/ppmsvgalib.html new file mode 100644 index 00000000..fddbe7cc --- /dev/null +++ b/ppmsvgalib.html @@ -0,0 +1,131 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<HTML><HEAD><TITLE>Ppmsvgalib User Manual</TITLE></HEAD> +<BODY> +<H1>ppmsvgalib</H1> +Updated: 11 May 2005 +<BR> +<A HREF="#index">Table Of Contents</A> + +<H2>NAME</H2> + +ppmsvgalib - display PPM image on Linux console using Svgalib + +<H2 id="synopsis">SYNOPSIS</H2> + +<B>ppmsvgalib</B> + +[<B>-mode=</B><I>mode</I>] + +<P>All options can be abbreviated to their shortest unique prefix. You +may use two hyphens instead of one to designate an option. You may +use either white space or an equals sign between an option name and its +value. + +<H2 id="description">DESCRIPTION</H2> + +<p>This program is part of <a href="index.html">Netpbm</a>. + +<B>ppmsvgalib</B> displays a PPM image on a Linux virtual console +using the Svgalib facility. Svgalib is a popular means of displaying +Graphics in Linux without the use of the X Window System. (To display +a Netpbm image in an X window, see <b>pamx</b>). + +<P>If you run <B>ppmsvgalib</B> with a version of Svgalib earlier than +1.9, you must run it with CAP_SYS_RAWIO capability (on most Linux +systems, that means you run it as superuser), because Svgalib uses the +<b>ioperm()</b> system call to access the console hardware. Newer +Svgalib has its own device driver, so you need only proper +permissions on a device special file to access the console. + +<P><B>ppmsvgalib</B> is not capable of using color mapped video modes. +These are the old video modes that are usually called "8 +bit" color modes. + +<P><B>ppmsvgalib</B> is a bare displayer. It won't do any +manipulation of the image and is not interactive in any way. If you +want a regular interactive graphics viewer that uses Svgalib, try +<B>zgv</B> (not part of Netpbm). + +<P>To exit <B>ppmsvgalib</B> while it is displaying your image, send +it a SIGINTR signal (normally, this means "hit control C"). + +<P><B>ppmsvgalib</B> draws a white border around the edges of the +screen. It does this to help you isolate problems between the image +you're displaying and the facilities you're using to display it. + +<P>(Note: if the image you're displaying reaches the edges of the +screen, it will replace the white border). + +<P><B>ppmsvgalib</B> places the image in the center of the screen. + +<P>If your image is too big to display in the video mode you selected, +<B>ppmsvgalib</B> fails. You can use <B>pamcut</B> to cut out a part +of the image to display or use <B>pamscale</B> to shrink the image to +fit. + +<P>If you want to play with <B>ppmsvgalib</B>, <B>ppmcie</B> is a good +way to generate a test image. + +<P>To be pedantic, we must observe that <B>ppmsvgalib</B> displays a +PPM image in the correct colors only if the display has a transfer +function which is the exact inverse of the gamma function that is +specified in the PPM specification. Happily, most CRT displays are +pretty close. + +<P>Running the PPM image through <B>pnmgamma</B> can help cause +<B>ppmsvgalib</B> to display the correct colors. + +<H2 id="options">OPTIONS</H2> + +<DL COMPACT> +<DT><B>-mode=</B><I>mode</I> + +<DD>This tells <B>ppmsvgalib</B> what video mode to use. <I>mode</I> +is the Svgalib video mode number. You can get a list of all the video +modes and their Svgalib video mode numbers with the program +<B>vgatest</B> that is packaged with Svgalib. (Unfortunately, the +various interesting programs that are packaged with Svgalib are +typically not installed on systems that have the Svgalib library +installed). + +<P>In practice, there are probably only two modes you'll ever care +about: 25 is the standard SVGA direct color mode, which is 1024 +columns by 768 rows with 8 bit red, green, and blue components for +each pixel and no fancy options. 28 is the same, but with the popular +higher resolution of 1280 x 1024. + +<P>But if you have an older video controller (with less than 4MB of +memory), those modes aren't available and you might like mode 19, +which is 640 x 480 and takes less than a megabyte of video memory. +This is a standard VGA video mode. + +</DL> + +<H2 id="seealso">SEE ALSO</H2> + +<B><A HREF="pamx.html">pamx</A></B>, +<B><A HREF="pamcut.html">pamcut</A></B>, +<B><A HREF="pamscale.html">pamscale</A></B>, +<B><A HREF="ppmcie.html">ppmcie</A></B>, +<B><A HREF="ppm.html">ppm</A></B>, +<B>zgv</B>, +<B>Svgalib</B>, +<B>vgatest</B> + +<H2 id="author">AUTHOR</H2> + +<p>By Bryan Henderson, January 2002. + +<P>Contributed to the public domain. + +<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="#author">AUTHOR</A> +</UL> +</BODY> +</HTML> |