<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
        {font-family:Wingdings;
        panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
        {font-family:"Cambria Math";
        panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
        {font-family:Calibri;
        panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
        {margin:0in;
        margin-bottom:.0001pt;
        font-size:12.0pt;
        font-family:"Times New Roman",serif;}
a:link, span.MsoHyperlink
        {mso-style-priority:99;
        color:#0563C1;
        text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
        {mso-style-priority:99;
        color:#954F72;
        text-decoration:underline;}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
        {mso-style-priority:34;
        margin-top:0in;
        margin-right:0in;
        margin-bottom:0in;
        margin-left:.5in;
        margin-bottom:.0001pt;
        font-size:12.0pt;
        font-family:"Times New Roman",serif;}
span.EmailStyle17
        {mso-style-type:personal-reply;
        font-family:"Calibri",sans-serif;
        color:#1F497D;}
.MsoChpDefault
        {mso-style-type:export-only;
        font-family:"Calibri",sans-serif;}
@page WordSection1
        {size:8.5in 11.0in;
        margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
        {page:WordSection1;}
/* List Definitions */
@list l0
        {mso-list-id:968167801;
        mso-list-type:hybrid;
        mso-list-template-ids:212390184 67698703 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l0:level1
        {mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level2
        {mso-level-number-format:alpha-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level3
        {mso-level-number-format:roman-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:right;
        text-indent:-9.0pt;}
@list l0:level4
        {mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level5
        {mso-level-number-format:alpha-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level6
        {mso-level-number-format:roman-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:right;
        text-indent:-9.0pt;}
@list l0:level7
        {mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level8
        {mso-level-number-format:alpha-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        text-indent:-.25in;}
@list l0:level9
        {mso-level-number-format:roman-lower;
        mso-level-tab-stop:none;
        mso-level-number-position:right;
        text-indent:-9.0pt;}
@list l1
        {mso-list-id:2067217517;
        mso-list-type:hybrid;
        mso-list-template-ids:285095268 1093990502 67698691 67698693 67698689 67698691 67698693 67698689 67698691 67698693;}
@list l1:level1
        {mso-level-start-at:0;
        mso-level-number-format:bullet;
        mso-level-text:-;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:24.75pt;
        text-indent:-.25in;
        font-family:"Calibri",sans-serif;
        mso-fareast-font-family:Calibri;
        mso-bidi-font-family:"Times New Roman";}
@list l1:level2
        {mso-level-number-format:bullet;
        mso-level-text:o;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:60.75pt;
        text-indent:-.25in;
        font-family:"Courier New";}
@list l1:level3
        {mso-level-number-format:bullet;
        mso-level-text:;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:96.75pt;
        text-indent:-.25in;
        font-family:Wingdings;}
@list l1:level4
        {mso-level-number-format:bullet;
        mso-level-text:;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:132.75pt;
        text-indent:-.25in;
        font-family:Symbol;}
@list l1:level5
        {mso-level-number-format:bullet;
        mso-level-text:o;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:168.75pt;
        text-indent:-.25in;
        font-family:"Courier New";}
@list l1:level6
        {mso-level-number-format:bullet;
        mso-level-text:;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:204.75pt;
        text-indent:-.25in;
        font-family:Wingdings;}
@list l1:level7
        {mso-level-number-format:bullet;
        mso-level-text:;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:240.75pt;
        text-indent:-.25in;
        font-family:Symbol;}
@list l1:level8
        {mso-level-number-format:bullet;
        mso-level-text:o;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:276.75pt;
        text-indent:-.25in;
        font-family:"Courier New";}
@list l1:level9
        {mso-level-number-format:bullet;
        mso-level-text:;
        mso-level-tab-stop:none;
        mso-level-number-position:left;
        margin-left:312.75pt;
        text-indent:-.25in;
        font-family:Wingdings;}
ol
        {margin-bottom:0in;}
ul
        {margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hmmm… I wonder if you just could use a pre-computed palette to control quantizing to 8 bits. You can supply a palette file (RGB or RGBA) and the MapServer will
 map 24/32-bit values to those in the palette. Format options are:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">     FORMATOPTION "PALETTE_FORCE=TRUE"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">    FORMATOPTION "PALETTE=palette.txt"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">This will definitely limit the colors in your output image to those you specify. The question is whether or not the anti-aliased colors will map to the right
 color and that will depend on your palette. I did write a simple test with a 5 color palette (black, white, red, green and blue) and it seems to work ok but that’s a very simple palette… Based on your application it might work though.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoListParagraph" style="margin-left:24.75pt;text-indent:-.25in;mso-list:l1 level1 lfo2">
<![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><a href="http://maps1.dnr.state.mn.us/cgi-bin/mapserv70?map=/usr/local/mapserver/apps/test/palette/test.map&mode=map">http://maps1.dnr.state.mn.us/cgi-bin/mapserv70?map=/usr/local/mapserver/apps/test/palette/test.map&mode=map</a>
 (24-bit)<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:24.75pt;text-indent:-.25in;mso-list:l1 level1 lfo2">
<![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><a href="http://maps1.dnr.state.mn.us/cgi-bin/mapserv70?map=/usr/local/mapserver/apps/test/palette/test.map&mode=map&map.imagetype=png8">http://maps1.dnr.state.mn.us/cgi-bin/mapserv70?map=/usr/local/mapserver/apps/test/palette/test.map&mode=map&map.imagetype=png8</a>
 (8-bit w/5 colors)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Steve<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> mapserver-users [mailto:mapserver-users-bounces@lists.osgeo.org]
<b>On Behalf Of </b>Erik H<br>
<b>Sent:</b> Monday, October 16, 2017 10:58 AM<br>
<b>To:</b> mapserver-users@lists.osgeo.org<br>
<b>Subject:</b> [mapserver-users] Draw roads WITHOUT anti-aliasing<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">I'm running a tiling server that uses MapServer 7.0.4 to generate PNGs.<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">My colleagues came up with an ingenious idea to animate traffic conditions that would require them to identify road segments based on their color. They asked me to generate tiles with a predetermined RGBA value per road segment. <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">I configured a layer of type LINE, with a STYLE section containing 'COLOR [palette]' (palette being a field in the database query). Initially, I thought I was creating the images my colleagues needed, but it seems that the anti-aliasing
 causes some pixels to have colors other than the one I specified; this prevents us from identifying the road segments.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">We can live without anti-aliasing, but I was unable to turn it off; I tried both the AGG/PNG and GD/PNG drivers and messed with various FORMATOPTION identifiers, but nothing seemed to make any difference.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Any suggestions?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Thanks.<o:p></o:p></p>
</div>
</div>
</div>
</body>
</html>