﻿{"id":11859,"date":"2023-08-08T09:00:00","date_gmt":"2023-08-08T07:00:00","guid":{"rendered":"https:\/\/www.sigterritoires.fr\/?p=11859"},"modified":"2023-08-10T12:50:09","modified_gmt":"2023-08-10T10:50:09","slug":"qgis-para-lidar-modelo-digital-de-terreno-dtm-com-cloudcompare","status":"publish","type":"post","link":"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-para-lidar-modelo-digital-de-terreno-dtm-com-cloudcompare\/","title":{"rendered":"QGis para LIDAR: modelo digital de terreno (DTM) com CloudCompare."},"content":{"rendered":"\n<p>QGis para LIDAR: modelo digital de terreno (DTM) Neste artigo, voc\u00ea encontrar\u00e1 a defini\u00e7\u00e3o de um modelo digital de terreno e, passo a passo, como criar um DTM a partir de uma nuvem LIDAR n\u00e3o classificada e classificada, usando o CloudCompare e o QGis.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Tutorial Processamento de dados HD LIDAR com o QGis.<\/h2>\n\n\n\n<p><a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/dados-lidar-no-qgis-3-32\/\">1- Dados LIDAR no QGis 3.32<\/a><\/p>\n\n\n\n<p><a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/carregamento-de-dados-ign-france-hd-lidar-no-qgis\/\">2- Descarregar os dados do IGN HD LIDAR e carreg\u00e1-los no QGis<\/a><\/p>\n\n\n\n<p><a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-3-32-ferramentas-para-dados-lidar\/\">3- Ferramentas para dados LIDAR no QGis 3.32<\/a><\/p>\n\n\n\n<p><a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-para-lidar-colorir-a-partir-de-uma-imagem\/\">4-colorir a partir de uma imagem<\/a><\/p>\n\n\n\n<p>5-<a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-para-lidar-colorir-a-partir-de-uma-imagem-com-lastools\/\" title=\"colorir a partir de uma imagem com LAStools\">colorir a partir de uma imagem com LAStools<\/a><\/p>\n\n\n\n<p>6- <a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-para-lidar-modelo-de-superficie-digital-mds-com-cloudcompare-e-lastools\/\" title=\"modelo de superf\u00edcie digital (MDS) com CloudCompare e LAStools\">modelo de superf\u00edcie digital (MDS) com CloudCompare e LAStools<\/a><\/p>\n\n\n\n<p>7- Cr\u00e9er un Mod\u00e8le Num\u00e9rique de Terrain avec CloudCompare<\/p>\n\n\n\n<p>Um Modelo Digital de Terreno (DTM) e um Modelo Digital de Superf\u00edcie (DSM) s\u00e3o dois tipos de representa\u00e7\u00e3o digital de um ambiente, geralmente baseados em dados LiDAR. Embora muitas vezes sejam usados de forma intercambi\u00e1vel, eles capturam informa\u00e7\u00f5es diferentes sobre a paisagem. No artigo anterior, vimos como gerar um DSM usando o CloudComapre ou o <a href=\"https:\/\/www.sigterritoires.fr\/index.php\/pt\/qgis-3-32-ferramentas-para-dados-lidar\/\">LAStools<\/a>. Aqui, veremos como gerar um DTM com o CloudCompare e, no pr\u00f3ximo artigo, como fazer isso com o LAStools.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Modelo Digital do Terreno (DTM):<\/h2>\n\n\n\n<p>Um modelo digital de terreno (DTM) representa a topografia real do solo sob todas as caracter\u00edsticas presentes na superf\u00edcie, como vegeta\u00e7\u00e3o, edif\u00edcios ou objetos feitos pelo homem. \u00c9 essencialmente o terreno natural, sem todas as estruturas e recursos elevados que n\u00e3o fazem parte da topografia subjacente. Um DTM geralmente \u00e9 obtido filtrando ou classificando os pontos LiDAR para reter apenas aqueles que correspondem ao solo. Dessa forma, o DTM fica mais pr\u00f3ximo da topografia real, fornecendo informa\u00e7\u00f5es valiosas para an\u00e1lise geomorfol\u00f3gica, hidrologia, mapeamento de declives etc.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Modelo Digital de Superf\u00edcie (DSM):<\/h2>\n\n\n\n<p>Um modelo digital de superf\u00edcie (DSM) representa a superf\u00edcie vis\u00edvel da paisagem, incluindo recursos acima do solo, como edif\u00edcios, vegeta\u00e7\u00e3o, ve\u00edculos etc. Ao contr\u00e1rio dos DTMs, os DSMs n\u00e3o filtram os objetos acima do solo e, portanto, capturam toda a topografia, incluindo estruturas e recursos elevados. Os dados LiDAR usados para criar um DTM incluem, portanto, todos os recursos presentes, tornando-os uma representa\u00e7\u00e3o mais completa da paisagem vista de cima.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Diferen\u00e7as entre DTM e DSM :<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Conte\u00fado: o DTM inclui apenas pontos que correspondem ao solo, enquanto o DTM inclui todos os pontos acima do solo, inclusive objetos e estruturas.<\/li>\n\n\n\n<li>Usos: Os DTMs s\u00e3o frequentemente usados para an\u00e1lises geomorfol\u00f3gicas, hidrol\u00f3gicas, geol\u00f3gicas e de planejamento do uso da terra. O DTM \u00e9 usado para modelagem visual, mapeamento urbano, gerenciamento de recursos naturais e outras aplica\u00e7\u00f5es que exigem uma vis\u00e3o completa da superf\u00edcie.<\/li>\n\n\n\n<li>An\u00e1lise: o DTM pode fornecer informa\u00e7\u00f5es precisas sobre a topografia real do solo, enquanto o DTM permite que os recursos acima do solo, como edif\u00edcios e vegeta\u00e7\u00e3o, sejam visualizados e analisados.<\/li>\n<\/ul>\n\n\n\n<p>Em resumo, o Modelo Digital de Terreno (DTM) concentra-se no terreno natural e elimina os recursos acima do solo, enquanto o Modelo Digital de Superf\u00edcie (DSM) inclui todos os recursos de eleva\u00e7\u00e3o. Cada um desses modelos tem seus pr\u00f3prios usos espec\u00edficos, dependendo dos requisitos de an\u00e1lise e visualiza\u00e7\u00e3o.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Cria\u00e7\u00e3o de um DTM a partir de uma nuvem classificada com o QGis<\/h2>\n\n\n\n<p>Em uma nuvem classificada, j\u00e1 temos as informa\u00e7\u00f5es necess\u00e1rias para gerar um DTM: classe 2 &#8211; Solo. De fato, todos os pontos correspondentes \u00e0 superf\u00edcie (edif\u00edcios, vegeta\u00e7\u00e3o, etc.) pertencem a outras classes.<\/p>\n\n\n\n<p>Portanto, podemos criar uma camada raster selecionando apenas os pontos da classe 2.<\/p>\n\n\n\n<p>Usaremos uma nuvem de pontos classificados pelo IGN LIDAR HD:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11830\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/nuage_lidar_classe_ign\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"nuage_lidar_classe_IGN\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=640%2C360&#038;ssl=1\" alt=\"nuage lidar hd class\u00e9 de l'IGN\" class=\"wp-image-11830\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/nuage_lidar_classe_IGN.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Onde manteremos apenas os pontos classificados como \u00ab\u00a0Solo\u00a0\u00bb:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11831\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/points_sol_nuage_lidar\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"points_sol_nuage_lidar\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=640%2C360&#038;ssl=1\" alt=\"classe &quot;sol&quot; du lidar IGN class\u00e9\" class=\"wp-image-11831\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_nuage_lidar.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Para fazer isso, usaremos uma das novas ferramentas aplic\u00e1veis \u00e0s camadas de nuvem de pontos: Exportar para raster (usando triangula\u00e7\u00e3o).<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"418\" data-attachment-id=\"11829\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/export_to_raster_tin_qgis\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?fit=2308%2C1507&amp;ssl=1\" data-orig-size=\"2308,1507\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"export_to_raster_tin_qgis\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?fit=640%2C418&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=640%2C418&#038;ssl=1\" alt=\"export raster using triangulation de QGis\" class=\"wp-image-11829\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=1024%2C669&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=300%2C196&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=768%2C501&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=1536%2C1003&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=2048%2C1337&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=241%2C158&amp;ssl=1 241w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?resize=264%2C172&amp;ssl=1 264w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_to_raster_tin_qgis.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Em Resolution of the density raster (Resolu\u00e7\u00e3o do raster de densidade), escolha o tamanho da malha de sa\u00edda.<\/p>\n\n\n\n<p>Em Advanced parameters -&gt; Filter expression, selecionamos Classification = 2, para reter apenas os pontos da classe 2.<\/p>\n\n\n\n<p>Digite um nome para o arquivo de sa\u00edda (aqui groundIGN.tif) e execute o comando.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11832\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_avec_ground_ign\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_avec_ground_ign\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=640%2C360&#038;ssl=1\" alt=\"mnt du nuage lidar class\u00e9 de l'IGN\" class=\"wp-image-11832\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_avec_ground_ign.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>A maneira visual mais eficaz de determinar a qualidade do DTM \u00e9 usar a Elevation Profile View:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11833\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/profil_elevation_qgis_mant_ign\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"profil_elevation_qgis_mant_ign\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=640%2C360&#038;ssl=1\" alt=\"vue \u00e9l\u00e9vation avec le nuage lidar ign et le mnt calcul\u00e9\" class=\"wp-image-11833\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/profil_elevation_qgis_mant_ign.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>A \u00e1rea azul mostra o DTM que acabamos de calcular.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Criando um DTM a partir de uma nuvem n\u00e3o classificada com o QGis.<\/h2>\n\n\n\n<p>Para esta parte do artigo, vamos trabalhar com a mesma nuvem de pontos de antes, mas com a classifica\u00e7\u00e3o removida. Acabamos com todos os pontos em uma \u00fanica classe 0.<\/p>\n\n\n\n<p>Portanto, precisamos de uma ferramenta que nos permita separar os pontos correspondentes ao solo do restante dos pontos. Existem v\u00e1rias, mas vamos come\u00e7ar com o CloudCompare, que considero a \u00ab\u00a0melhor\u00a0\u00bb, pois nos permite realizar essa tarefa visualizando as diferentes etapas dos testes. Esses testes s\u00e3o necess\u00e1rios porque os par\u00e2metros de tratamento precisam ser adaptados a cada nuvem de acordo com v\u00e1rios crit\u00e9rios.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">C\u00e1lculo de DTM com o CloudCompare.<\/h2>\n\n\n\n<p>O CSF (Cloth Simulation Filter, filtro de simula\u00e7\u00e3o de tecido) \u00e9 um algoritmo de filtro usado no software CloudCompare para processar nuvens de pontos lidar. Ele \u00e9 usado principalmente para remover ru\u00eddos e discrep\u00e2ncias das nuvens de pontos, especialmente em \u00e1reas onde h\u00e1 superf\u00edcies complexas, como \u00e1rvores, mas tamb\u00e9m para distinguir entre pontos terrestres e a\u00e9reos.<\/p>\n\n\n\n<p>O nome do filtro CSF vem da simula\u00e7\u00e3o de tecido, devido \u00e0 maneira como ele modela a estrutura da nuvem de pontos. A ideia b\u00e1sica por tr\u00e1s do filtro CSF \u00e9 modelar os pontos como se estivessem presos a \u00ab\u00a0tecidos\u00a0\u00bb virtuais que se dobram e se deformam de acordo com a densidade de pontos nas \u00e1reas circundantes. As \u00e1reas em que os \u00ab\u00a0tecidos\u00a0\u00bb s\u00e3o altamente deformados s\u00e3o consideradas como tendo superf\u00edcies complexas, como vegeta\u00e7\u00e3o ou edif\u00edcios.<\/p>\n\n\n\n<p>Veja a seguir como o filtro CSF geralmente funciona no CloudCompare:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>C\u00e1lculo de normais<\/strong>: o filtro CSF come\u00e7a calculando as normais dos pontos na nuvem. As normais s\u00e3o vetores perpendiculares \u00e0s superf\u00edcies locais dos pontos.<\/li>\n\n\n\n<li><strong>Cria\u00e7\u00e3o de \u00ab\u00a0tecidos\u00a0\u00bb<\/strong>: o filtro divide o espa\u00e7o em uma grade 3D e atribui cada ponto a um \u00ab\u00a0tecido\u00a0\u00bb virtual de acordo com sua posi\u00e7\u00e3o e suas normais.<\/li>\n\n\n\n<li><strong>Simula\u00e7\u00e3o de tecido<\/strong>: o filtro simula como esses \u00ab\u00a0tecidos\u00a0\u00bb reagiriam sob for\u00e7as como a gravidade. Os \u00ab\u00a0tecidos\u00a0\u00bb se dobram e se deformam de acordo com a densidade dos pontos ao redor deles.<\/li>\n\n\n\n<li><strong>Detec\u00e7\u00e3o d<\/strong>e ru\u00eddo: As \u00e1reas em que os \u00ab\u00a0tecidos\u00a0\u00bb est\u00e3o altamente deformados s\u00e3o consideradas \u00e1reas de ru\u00eddo ou superf\u00edcies complexas. Os pontos associados a essas \u00e1reas s\u00e3o rotulados como fora do solo.<\/li>\n\n\n\n<li><strong>Filtragem<\/strong>: os pontos marcados como fora do solo s\u00e3o removidos da nuvem de pontos, deixando para tr\u00e1s uma vers\u00e3o filtrada e limpa da nuvem.<\/li>\n<\/ol>\n\n\n\n<p>O filtro de simula\u00e7\u00e3o de tecido (CSF) no CloudCompare pode ser usado para separar os pontos do solo de outros pontos em uma nuvem de pontos LiDAR. Isso \u00e9 particularmente \u00fatil para isolar a verdadeira topografia do terreno de recursos elevados, como edif\u00edcios, vegeta\u00e7\u00e3o ou outras estruturas.<\/p>\n\n\n\n<p>\u00c9 importante observar que o sucesso do uso do filtro CSF para separar pontos de solo de outros depender\u00e1 dos par\u00e2metros escolhidos e da complexidade da paisagem. Pode ser necess\u00e1rio ajustar os par\u00e2metros do filtro v\u00e1rias vezes para obter os melhores resultados.<\/p>\n\n\n\n<p>\u00c9 importante observar que o sucesso do uso do filtro CSF para separar os pontos de solo de outros depender\u00e1 dos par\u00e2metros escolhidos e da complexidade da paisagem. Pode ser necess\u00e1rio ajustar as configura\u00e7\u00f5es do filtro v\u00e1rias vezes para obter os melhores resultados.<\/p>\n\n\n\n<p>Come\u00e7amos carregando nossa nuvem de pontos n\u00e3o classificada no CloudCompare:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11834\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/lidar_non_classe_cloudcompare\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"lidar_non_classe_cloudcompare\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=640%2C360&#038;ssl=1\" alt=\"nuage de points non class\u00e9 dans cloudcompare\" class=\"wp-image-11834\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Abra a janela do filtro CSF no menu Plugins-&gt;Filtro CSF.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"426\" data-attachment-id=\"11835\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/menu_plugin_csffilter\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?fit=1318%2C878&amp;ssl=1\" data-orig-size=\"1318,878\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"menu_plugin_csffilter\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?fit=640%2C426&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?resize=640%2C426&#038;ssl=1\" alt=\"menu csf filter de cloudcompare\" class=\"wp-image-11835\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?resize=1024%2C682&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?resize=300%2C200&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?resize=768%2C512&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/menu_plugin_csffilter.png?w=1318&amp;ssl=1 1318w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Voc\u00ea tem a janela do plug-in com um primeiro par\u00e2metro a ser determinado, o tipo de inclina\u00e7\u00e3o do terreno. H\u00e1 tr\u00eas tipos:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>terreno plano<\/li>\n\n\n\n<li>terreno montanhoso<\/li>\n\n\n\n<li>terreno muito acidentado<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"867\" data-attachment-id=\"11836\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/type_de_pente_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?fit=1207%2C1635&amp;ssl=1\" data-orig-size=\"1207,1635\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"type_de_pente_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?fit=640%2C867&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?resize=640%2C867&#038;ssl=1\" alt=\"dialogue plugin csf filter de cloudcompare\" class=\"wp-image-11836\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?resize=756%2C1024&amp;ssl=1 756w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?resize=221%2C300&amp;ssl=1 221w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?resize=768%2C1040&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?resize=1134%2C1536&amp;ssl=1 1134w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/type_de_pente_filtre_csf.png?w=1207&amp;ssl=1 1207w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Em nosso caso, temos um terreno montanhoso.<\/p>\n\n\n\n<p>Em seguida, v\u00e1 para a guia Advanced parameters settings (Configura\u00e7\u00f5es de par\u00e2metros avan\u00e7ados)<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"867\" data-attachment-id=\"11838\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/parametres_csf_filter\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?fit=1207%2C1635&amp;ssl=1\" data-orig-size=\"1207,1635\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"parametres_csf_filter\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?fit=640%2C867&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?resize=640%2C867&#038;ssl=1\" alt=\"advanced parameters du filtre csf de cloudcompare\" class=\"wp-image-11838\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?resize=756%2C1024&amp;ssl=1 756w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?resize=221%2C300&amp;ssl=1 221w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?resize=768%2C1040&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?resize=1134%2C1536&amp;ssl=1 1134w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/parametres_csf_filter.png?w=1207&amp;ssl=1 1207w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Os dois par\u00e2metros a serem definidos s\u00e3o<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Cloth resolution<\/h3>\n\n\n\n<p>O par\u00e2metro \u00ab\u00a0Cloth resolution\u00a0\u00bb no CSF (Filtro de simula\u00e7\u00e3o de tecido) do CloudCompare refere-se ao tamanho da grade tridimensional usada para modelar o \u00ab\u00a0tecido\u00a0\u00bb virtual no processo de simula\u00e7\u00e3o.<\/p>\n\n\n\n<p>Quando voc\u00ea aplica o filtro CSF para filtrar uma nuvem de pontos, ele divide o espa\u00e7o em regi\u00f5es menores usando uma grade 3D. Cada regi\u00e3o \u00e9 tratada como um \u00ab\u00a0tecido\u00a0\u00bb virtual que reage \u00e0s for\u00e7as aplicadas, simulando o movimento e a deforma\u00e7\u00e3o de um tecido real. O par\u00e2metro \u00ab\u00a0Cloth resolution\u00a0\u00bb (Resolu\u00e7\u00e3o do tecido) controla o tamanho dessa grade.<\/p>\n\n\n\n<p>Uma resolu\u00e7\u00e3o mais alta significa que a grade ser\u00e1 mais fina, permitindo que o filtro CSF capture melhor os detalhes sutis e as varia\u00e7\u00f5es na nuvem de pontos. Entretanto, uma resolu\u00e7\u00e3o mais alta tamb\u00e9m pode aumentar o tempo de computa\u00e7\u00e3o e o consumo de recursos.<\/p>\n\n\n\n<p>Uma resolu\u00e7\u00e3o mais baixa significa que a grade ser\u00e1 mais grosseira, o que pode acelerar o processo de c\u00e1lculo, mas pode perder alguns dos detalhes mais finos da nuvem de pontos.<\/p>\n\n\n\n<p>A escolha da resolu\u00e7\u00e3o depender\u00e1 da complexidade de seus dados, do tamanho da nuvem de pontos e da finalidade de sua an\u00e1lise. Se estiver trabalhando com \u00e1reas complexas, pode ser desej\u00e1vel uma resolu\u00e7\u00e3o mais alta para capturar detalhes. Se voc\u00ea tiver uma nuvem de pontos grande e precisar de resultados mais rapidamente, uma resolu\u00e7\u00e3o mais baixa pode ser adequada.<\/p>\n\n\n\n<p>Como sempre, \u00e9 aconselh\u00e1vel fazer experi\u00eancias com diferentes valores de resolu\u00e7\u00e3o e verificar visualmente os resultados para determinar qual resolu\u00e7\u00e3o funciona melhor para seus dados espec\u00edficos.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Classification threshold<\/h3>\n\n\n\n<p>O par\u00e2metro \u00ab\u00a0Classification threshold\u00a0\u00bb no Filtro de simula\u00e7\u00e3o de tecido (CSF) do CloudCompare \u00e9 usado para especificar um limite de deforma\u00e7\u00e3o al\u00e9m do qual os pontos na nuvem de pontos ser\u00e3o considerados n\u00e3o classificados, ou seja, ser\u00e3o atribu\u00eddos a fora do solo.<\/p>\n\n\n\n<p>Quando o filtro CSF \u00e9 aplicado, ele simula a deforma\u00e7\u00e3o de uma grade tridimensional (representando \u00ab\u00a0tecidos\u00a0\u00bb virtuais) com base nos pontos da nuvem. As \u00e1reas em que os tecidos s\u00e3o altamente deformados s\u00e3o interpretadas como \u00e1reas com recursos complexos, como vegeta\u00e7\u00e3o ou objetos elevados.<\/p>\n\n\n\n<p>O par\u00e2metro \u00ab\u00a0Classification threshold\u00a0\u00bb \u00e9 usado para controlar a deforma\u00e7\u00e3o m\u00e1xima tolerada antes que um ponto seja considerado acima do solo. Em outras palavras, se a deforma\u00e7\u00e3o de um ponto exceder o limite especificado, ele n\u00e3o ser\u00e1 atribu\u00eddo \u00e0 classe de solo \u00ab\u00a0particular\u00a0\u00bb, marcando-o como potencialmente \u00ab\u00a0fora do solo\u00a0\u00bb.<\/p>\n\n\n\n<p>O ajuste do par\u00e2metro \u00ab\u00a0Classification threshold\u00a0\u00bb pode controlar o n\u00edvel de detalhes que o filtro CSF usar\u00e1 para diferenciar as caracter\u00edsticas complexas do solo. Um valor mais alto tornar\u00e1 o filtro mais sens\u00edvel a caracter\u00edsticas complexas. Um valor mais baixo tornar\u00e1 o filtro menos sens\u00edvel e poder\u00e1 ser usado para filtrar apenas caracter\u00edsticas muito pronunciadas.<\/p>\n\n\n\n<p>Como sempre, \u00e9 recomend\u00e1vel que voc\u00ea experimente diferentes valores de limite e verifique visualmente os resultados para determinar qual valor funciona melhor para seus dados espec\u00edficos.<\/p>\n\n\n\n<p>De modo geral, consideramos que o valor do limite de classifica\u00e7\u00e3o deve ser o dobro do valor definido para a resolu\u00e7\u00e3o Cloth.<\/p>\n\n\n\n<p>Ent\u00e3o, vamos ao teste. Um bom ponto de partida \u00e9 definir a resolu\u00e7\u00e3o Cloth como 0,2 metro e os Classification threshold como 0,4 metro.<\/p>\n\n\n\n<p>Executamos o filtro e encontramos uma nova camada de resultados no CloudCompare com duas subcamadas:<\/p>\n\n\n\n<p>A primeira cont\u00e9m os pontos classificados como \u00ab\u00a0solo\u00a0\u00bb pelo filtro CSF.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11840\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/premier_passage_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"premier_passage_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=640%2C360&#038;ssl=1\" alt=\"premier passage csf, couche ground\" class=\"wp-image-11840\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/premier_passage_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>A segunda cont\u00e9m os pontos classificados como \u00ab\u00a0acima do solo\u00a0\u00bb pelo filtro CSF.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11843\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/points_hors_sol_filtre_csf-1\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"points_hors_sol_filtre_csf-1\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=640%2C360&#038;ssl=1\" alt=\"premier passage filtre csf couche off-ground\" class=\"wp-image-11843\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_filtre_csf-1.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Vamos tentar uma nova combina\u00e7\u00e3o de par\u00e2metros para refinar a detec\u00e7\u00e3o de pontos acima do solo. Para isso, vamos ativar a camada \u00ab\u00a0solo\u00a0\u00bb que acabamos de calcular e aplicar o filtro CSF a ela, com os par\u00e2metros Cloth resolution (Resolu\u00e7\u00e3o de tecido) em 0,4 metro e Classification thresholds (Limites de classifica\u00e7\u00e3o) em 0,8 metro.<\/p>\n\n\n\n<p>Teremos ent\u00e3o duas novas camadas, uma com pontos que s\u00e3o considerados \u00ab\u00a0solo\u00a0\u00bb e outra com pontos que foram considerados \u00ab\u00a0solo\u00a0\u00bb pela primeira passagem do filtro CSF, mas que agora s\u00e3o considerados \u00ab\u00a0acima do solo\u00a0\u00bb com os novos par\u00e2metros.<\/p>\n\n\n\n<p>Temos a camada \u00ab\u00a0solo\u00a0\u00bb<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11844\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/points_sol_deuxieme_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"points_sol_deuxieme_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=640%2C360&#038;ssl=1\" alt=\"deuxi\u00e8me filtre csf couche ground\" class=\"wp-image-11844\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_sol_deuxieme_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>E temos os pontos que agora est\u00e3o \u00ab\u00a0acima do solo\u00a0\u00bb.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11845\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/points_hors_sol_deuxieme_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"points_hors_sol_deuxieme_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=640%2C360&#038;ssl=1\" alt=\"deuxi\u00e8me filtre csf couche off-ground\" class=\"wp-image-11845\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_deuxieme_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Visualmente, j\u00e1 podemos dizer que nosso resultado deve ser satisfat\u00f3rio. Mas, para ter certeza, repetiremos a opera\u00e7\u00e3o uma terceira vez, desta vez com a resolu\u00e7\u00e3o Cloth em 0,8 metro e os limites de classifica\u00e7\u00e3o em 1,6 metro.<\/p>\n\n\n\n<p>Teremos ent\u00e3o duas novas camadas, uma com pontos que s\u00e3o considerados \u00ab\u00a0solo\u00a0\u00bb e outra com pontos que foram considerados \u00ab\u00a0solo\u00a0\u00bb pela segunda passagem do filtro CSF, mas que agora s\u00e3o considerados \u00ab\u00a0acima do solo\u00a0\u00bb com os novos par\u00e2metros.<\/p>\n\n\n\n<p>Temos a camada \u00ab\u00a0solo\u00a0\u00bb<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11846\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/point_sol_troisieme_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"point_sol_troisieme_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=640%2C360&#038;ssl=1\" alt=\"troisi\u00e8me filtre csf couche ground\" class=\"wp-image-11846\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/point_sol_troisieme_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Onde agora voc\u00ea v\u00ea \u00e1reas bastante extensas sem nenhum ponto.<\/p>\n\n\n\n<p>E a camada \u00ab\u00a0acima do solo\u00a0\u00bb<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"360\" data-attachment-id=\"11847\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/points_hors_sol_troisieme_filtrecsf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?fit=3842%2C2160&amp;ssl=1\" data-orig-size=\"3842,2160\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"points_hors_sol_troisieme_filtrecsf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?fit=640%2C360&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=640%2C360&#038;ssl=1\" alt=\"troisi\u00e8me filtre csf couche off-ground\" class=\"wp-image-11847\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?resize=2048%2C1151&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/points_hors_sol_troisieme_filtrecsf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Para poder validar a combina\u00e7\u00e3o correta de par\u00e2metros, salvamos as camadas de \u00ab\u00a0solo\u00a0\u00bb obtidas como nuvens de pontos. Voc\u00ea pode salvar a nuvem de pontos filtrada selecionando \u00ab\u00a0File\u00a0\u00bb (Arquivo) &gt; \u00ab\u00a0Save As\u00a0\u00bb (Salvar como) no menu para salvar uma nova c\u00f3pia com as modifica\u00e7\u00f5es feitas pelo filtro CSF.<\/p>\n\n\n\n<p>Portanto, temos tr\u00eas novas nuvens de pontos, ground02\u2026 para o resultado do primeiro filtro CSF, ground04\u2026 para o segundo e ground08\u2026 para o terceiro, que carregamos no QGis. Tamb\u00e9m carregamos a nuvem de pontos original n\u00e3o classificada, nc\u2026<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"226\" data-attachment-id=\"11849\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/classe_sol_filtres_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?fit=5035%2C1775&amp;ssl=1\" data-orig-size=\"5035,1775\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"classe_sol_filtres_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?fit=640%2C226&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=640%2C226&#038;ssl=1\" alt=\"les trois nuages de points en sortie de cloudcompare\" class=\"wp-image-11849\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=1024%2C361&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=300%2C106&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=768%2C271&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=1536%2C541&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?resize=2048%2C722&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/classe_sol_filtres_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Intuitivamente, o resultado do filtro 0.4 parece ser o melhor. O filtro 0.2 tem um pouco mais de \u00ab\u00a0solo\u00a0\u00bb e o filtro 0.8 n\u00e3o \u00e9 suficiente em algumas \u00e1reas.<\/p>\n\n\n\n<p>Agora podemos criar os tr\u00eas DTMs e comparar o resultado com a nuvem de pontos original.<\/p>\n\n\n\n<p>Para fazer isso, como no primeiro exemplo, usamos a ferramenta Exportar para raster (usando triangula\u00e7\u00e3o). Entretanto, como aqui s\u00f3 temos pontos correspondentes ao solo, n\u00e3o precisamos aplicar um filtro. Basta definir o espa\u00e7amento da grade do DTM de sa\u00edda e o nome do arquivo de sa\u00edda.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"426\" data-attachment-id=\"11850\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/export_raster_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?fit=2083%2C1385&amp;ssl=1\" data-orig-size=\"2083,1385\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"export_raster_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?fit=640%2C426&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=640%2C426&#038;ssl=1\" alt=\"export to raster using triangulation\" class=\"wp-image-11850\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=1024%2C681&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=300%2C199&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=768%2C511&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=1536%2C1021&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?resize=2048%2C1362&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/export_raster_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Temos ent\u00e3o tr\u00eas rasters com os DTMs correspondentes<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"230\" data-attachment-id=\"11851\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_filtre_csf\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?fit=4987%2C1793&amp;ssl=1\" data-orig-size=\"4987,1793\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_filtre_csf\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?fit=640%2C230&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=640%2C230&#038;ssl=1\" alt=\"les trois mnt calcul\u00e9s avec qgis\" class=\"wp-image-11851\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=1024%2C368&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=300%2C108&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=768%2C276&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=1536%2C552&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?resize=2048%2C736&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Como voc\u00ea pode ver, no DTM 0.2 ainda podemos ver as pegadas dos edif\u00edcios classificados como \u00ab\u00a0solo\u00a0\u00bb. Para ver a diferen\u00e7a entre os DTMs 0.4 e 0.8, usamos a Elevation Profile View.<\/p>\n\n\n\n<p>Exibimos a nuvem de pontos original e o DTM calculado a partir da classe \u00ab\u00a0ground\u00a0\u00bb do IGN. Consideraremos esse DTM como o melhor DTM.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"314\" data-attachment-id=\"11852\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_de_reference\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?fit=3283%2C1614&amp;ssl=1\" data-orig-size=\"3283,1614\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_de_reference\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?fit=640%2C314&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=640%2C314&#038;ssl=1\" alt=\"vue de profil du mnt de r\u00e9f\u00e9rence\" class=\"wp-image-11852\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=1024%2C503&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=300%2C147&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=768%2C378&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=1536%2C755&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?resize=2048%2C1007&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_de_reference.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Nesse perfil, temos caracter\u00edsticas do terreno, vegeta\u00e7\u00e3o baixa e alta e edif\u00edcios.<\/p>\n\n\n\n<p>Se exibirmos o DTM 0.2 em amarelo, teremos:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"307\" data-attachment-id=\"11853\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_filtre_csf_02\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?fit=3304%2C1583&amp;ssl=1\" data-orig-size=\"3304,1583\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_filtre_csf_02\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?fit=640%2C307&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=640%2C307&#038;ssl=1\" alt=\"vue de profil du r\u00e9sultat du filtre csf 0.2\" class=\"wp-image-11853\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=1024%2C491&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=300%2C144&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=768%2C368&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=1536%2C736&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?resize=2048%2C981&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_02.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>A vegeta\u00e7\u00e3o baixa e alta foram classificadas como \u00ab\u00a0acima do solo\u00a0\u00bb, mas as edifica\u00e7\u00f5es ainda est\u00e3o inclu\u00eddas nos pontos do \u00ab\u00a0solo\u00a0\u00bb.<\/p>\n\n\n\n<p>Se exibirmos o DTM 0.4 em azul, teremos:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"313\" data-attachment-id=\"11854\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_filtre_csf_04\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?fit=3324%2C1626&amp;ssl=1\" data-orig-size=\"3324,1626\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_filtre_csf_04\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?fit=640%2C313&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=640%2C313&#038;ssl=1\" alt=\"vue de profil du r\u00e9sultat du filtre csf 0.4\" class=\"wp-image-11854\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=1024%2C501&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=300%2C147&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=768%2C376&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=1536%2C751&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?resize=2048%2C1002&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_04.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Os edif\u00edcios agora s\u00e3o exclu\u00eddos e o resultado se funde com o do IGN.<\/p>\n\n\n\n<p>Finalmente, se exibirmos o DTM 0.8 em vermelho, teremos:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"318\" data-attachment-id=\"11855\" data-permalink=\"https:\/\/www.sigterritoires.fr\/index.php\/qgis-pour-lidarmodele-numerique-de-terrain-mnt-avec-cloudcompare\/mnt_filtre_csf_08\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?fit=3306%2C1644&amp;ssl=1\" data-orig-size=\"3306,1644\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"mnt_filtre_csf_08\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?fit=640%2C318&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=640%2C318&#038;ssl=1\" alt=\"vue de profil du r\u00e9sultat du filtre csf 0.8\" class=\"wp-image-11855\" srcset=\"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=1024%2C509&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=300%2C149&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=768%2C382&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=1536%2C764&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?resize=2048%2C1018&amp;ssl=1 2048w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?w=1280&amp;ssl=1 1280w, https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/mnt_filtre_csf_08.png?w=1920&amp;ssl=1 1920w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Ao excluir pontos que fazem parte do terreno, criamos zonas vazias que s\u00e3o interpoladas usando apenas as bordas das zonas. Ainda temos um bom c\u00e1lculo do terreno em \u00e1reas de vegeta\u00e7\u00e3o e edif\u00edcios, mas alguns recursos do terreno desaparecem.<\/p>\n\n\n\n<p>Concluindo, nossos par\u00e2metros com Cloth resolution de 0,4 metro e Classification thresholds de 0,8 metro, que nos pareceram ser a melhor combina\u00e7\u00e3o, j\u00e1 que o filtro CSF foi calculado no CloudCompare, acabaram sendo os melhores. Eles nos permitem obter um DTM equivalente ao calculado a partir dos dados classificados do IGN.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>QGis para LIDAR: modelo digital de terreno (DTM) Neste artigo, voc\u00ea encontrar\u00e1 a defini\u00e7\u00e3o de um modelo digital de terreno e, passo a passo, como criar um DTM a partir de uma nuvem LIDAR n\u00e3o classificada&hellip;<\/p>\n","protected":false},"author":1,"featured_media":11834,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"give_campaign_id":0,"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"sfsi_plus_gutenberg_text_before_share":"","sfsi_plus_gutenberg_show_text_before_share":"","sfsi_plus_gutenberg_icon_type":"","sfsi_plus_gutenberg_icon_alignemt":"","sfsi_plus_gutenburg_max_per_row":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[2426],"tags":[2447,2621,2436,2623,2619,2434,2160],"class_list":["post-11859","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-lidar-pt","tag-cloudcompare","tag-csf-filter","tag-lidar-pt","tag-mdt-pt","tag-modelo-digital-de-terreno","tag-nuvens-de-pontos","tag-qgis-pt"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.sigterritoires.fr\/wp-content\/uploads\/2023\/08\/lidar_non_classe_cloudcompare.png?fit=3842%2C2160&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p6XU0A-35h","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/posts\/11859","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/comments?post=11859"}],"version-history":[{"count":0,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/posts\/11859\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/media\/11834"}],"wp:attachment":[{"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/media?parent=11859"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/categories?post=11859"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sigterritoires.fr\/index.php\/wp-json\/wp\/v2\/tags?post=11859"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}