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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I hope this is the right place and approach to get support for my issue. Apologies if it isn’t.<o:p></o:p></p>
<p class="MsoNormal">Question also posted to the Gis reddit if I’m more likely to get help as replies on there (<a href="https://www.reddit.com/r/gis/comments/8dnsr2/could_a_more_experienced_giser_tell_me_why_i_get/">https://www.reddit.com/r/gis/comments/8dnsr2/could_a_more_experienced_giser_tell_me_why_i_get/</a>)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In PostGis I run the following query:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> SELECT<o:p></o:p></p>
<p class="MsoNormal"> (ST_MetaData(ST_AddBand(ST_MakeEmptyRaster(1, 1, 2, 2, 10::FLOAT, 10::FLOAT, 0, 0), '1BB'))).*<o:p></o:p></p>
<p class="MsoNormal"> UNION ALL<o:p></o:p></p>
<p class="MsoNormal"> SELECT<o:p></o:p></p>
<p class="MsoNormal"> (ST_MetaData(ST_AsRaster(<o:p></o:p></p>
<p class="MsoNormal"> ST_MakeEnvelope(2, 2, 3, 3),<o:p></o:p></p>
<p class="MsoNormal"> 0.5 :: FLOAT, 0.5 :: FLOAT,<o:p></o:p></p>
<p class="MsoNormal"> 0, 0, '1BB', 1, 0, 0, 0, true<o:p></o:p></p>
<p class="MsoNormal"> ))).*<o:p></o:p></p>
<p class="MsoNormal"> UNION ALL<o:p></o:p></p>
<p class="MsoNormal"> SELECT<o:p></o:p></p>
<p class="MsoNormal"> (ST_MetaData(ST_AsRaster(<o:p></o:p></p>
<p class="MsoNormal"> ST_MakeEnvelope(2, 2, 3, 3),<o:p></o:p></p>
<p class="MsoNormal"> 1 :: FLOAT, 1 :: FLOAT,<o:p></o:p></p>
<p class="MsoNormal"> 0, 0, '1BB', 1, 0, 0, 0, true<o:p></o:p></p>
<p class="MsoNormal"> ))).*<o:p></o:p></p>
<p class="MsoNormal"> UNION ALL<o:p></o:p></p>
<p class="MsoNormal"> SELECT<o:p></o:p></p>
<p class="MsoNormal"> (ST_MetaData(ST_AsRaster(<o:p></o:p></p>
<p class="MsoNormal"> ST_MakeEnvelope(2, 2, 3, 3),<o:p></o:p></p>
<p class="MsoNormal"> 10 :: FLOAT, 10 :: FLOAT,<o:p></o:p></p>
<p class="MsoNormal"> 0, 0, '1BB', 1, 0, 0, 0, true<o:p></o:p></p>
<p class="MsoNormal"> ))).*<o:p></o:p></p>
<p class="MsoNormal"> ;<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">That gives me results:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> upperleftx | upperlefty | width | height | scalex | scaley | skewx | skewy | srid | numbands<o:p></o:p></p>
<p class="MsoNormal"> -----------+------------+-------+--------+--------+--------+-------+-------+------+----------<o:p></o:p></p>
<p class="MsoNormal"> 2 | 2 | 1 | 1 | 10 | 10 | 0 | 0 | 0 | 1<o:p></o:p></p>
<p class="MsoNormal"> 2 | 2 | 2 | 2 | 0.5 | 0.5 | 0 | 0 | 0 | 1<o:p></o:p></p>
<p class="MsoNormal"> 2 | 2 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1<o:p></o:p></p>
<p class="MsoNormal"> 0 | -10 | 2 | 2 | 10 | 10 | 0 | 0 | 0 | 1<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What gets me is the final row. Why would the biggest pixel scale give a 2x2 raster?<o:p></o:p></p>
<p class="MsoNormal">If I dump the points I see<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> {{NULL,NULL},{1,NULL}}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So it's created some null pixels for no reason that I understand.<o:p></o:p></p>
<p class="MsoNormal">Is this a bug? Could someone explain this behaviour for me?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:8.0pt;line-height:106%"><b><span style="font-size:12.0pt;line-height:106%;font-family:"Trebuchet MS",sans-serif;color:#004B8D">David Swain<o:p></o:p></span></b></p>
<p class="MsoNormal" style="margin-bottom:8.0pt;line-height:106%"><span style="font-size:10.0pt;line-height:106%;font-family:"Trebuchet MS",sans-serif;color:#6FABDD"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:8.0pt;line-height:106%"><b><span style="font-size:10.0pt;line-height:106%;font-family:"Trebuchet MS",sans-serif;color:#1899D6"><a href="https://www.linkedin.com/company-beta/202826/"><span style="color:#1899D6;font-weight:normal;text-decoration:none">Follow
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