From 52e1b015978d7f02b139d4e598a8bd49fe98fd17 Mon Sep 17 00:00:00 2001
From: matlabbe <matlabbe@gmail.com>
Date: Mon, 4 Mar 2024 17:05:17 -0800
Subject: [PATCH] Fixed assert when exporting textured mesh with both multiband
 and blending enabled with grayscale images

---
 corelib/src/util3d_surface.cpp    | 42 +++++++++++++++++++++----------
 guilib/src/ExportCloudsDialog.cpp |  2 +-
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/corelib/src/util3d_surface.cpp b/corelib/src/util3d_surface.cpp
index 6bafca8a5b..2dca472b40 100644
--- a/corelib/src/util3d_surface.cpp
+++ b/corelib/src/util3d_surface.cpp
@@ -2398,7 +2398,7 @@ bool multiBandTexturing(
 	std::string tmpImageDirectory = outputDirectory+"/rtabmap_tmp_textures";
 	UDirectory::removeDir(tmpImageDirectory);
 	UDirectory::makeDir(tmpImageDirectory);
-	UINFO("Temporary saving images in directory \"%s\"...", tmpImageDirectory.c_str());
+	UINFO("Temporary saving images from %ld nodes in directory \"%s\"...", cameraPoses.size(), tmpImageDirectory.c_str());
 	int viewId = 0;
 	for(std::map<int, Transform>::const_iterator iter = cameraPoses.lower_bound(1); iter!=cameraPoses.end(); ++iter)
 	{
@@ -2510,28 +2510,45 @@ bool multiBandTexturing(
 				imageSize.height = image.rows;
 				imageSize.width = image.cols;
 			}
+
 			UASSERT(image.cols % imageSize.width == 0);
 			cv::Mat imageRoi = image.colRange(i*imageSize.width, (i+1)*imageSize.width);
+
 			if(gains.find(camId) != gains.end() &&
 			   gains.at(camId).find(i) != gains.at(camId).end())
 			{
 				const cv::Vec4d & g = gains.at(camId).at(i);
-				std::vector<cv::Mat> channels;
-				cv::split(imageRoi, channels);
+				if(imageRoi.channels() == 1)
+				{
+					cv::multiply(imageRoi, g.val[0], imageRoi);
+				}
+				else
+				{
+					std::vector<cv::Mat> channels;
+					cv::split(imageRoi, channels);
 
-				// assuming BGR
-				cv::multiply(channels[0], g.val[gainRGB?3:0], channels[0]);
-				cv::multiply(channels[1], g.val[gainRGB?2:0], channels[1]);
-				cv::multiply(channels[2], g.val[gainRGB?1:0], channels[2]);
+					// assuming BGR
+					cv::multiply(channels[0], g.val[gainRGB?3:0], channels[0]);
+					cv::multiply(channels[1], g.val[gainRGB?2:0], channels[1]);
+					cv::multiply(channels[2], g.val[gainRGB?1:0], channels[2]);
 
-				cv::Mat output;
-				cv::merge(channels, output);
-				imageRoi = output;
+					cv::Mat output;
+					cv::merge(channels, output);
+					imageRoi = output;
+				}
 			}
 
 			if(blendingGains.find(camId) != blendingGains.end() &&
 			   blendingGains.at(camId).find(i) != blendingGains.at(camId).end())
 			{
+				// Should be color for blending options
+				if(imageRoi.channels() == 1)
+				{
+					cv::Mat imageRoiColor;
+					cv::cvtColor(imageRoi, imageRoiColor, CV_GRAY2BGR);
+					imageRoi = imageRoiColor;
+				}
+
 				cv::Mat g = blendingGains.at(camId).at(i);
 				cv::Mat dst;
 				cv::blur(g, dst, cv::Size(3,3));
@@ -2559,9 +2576,7 @@ bool multiBandTexturing(
 			sfmData.intrinsics.insert(std::make_pair((IndexT)viewId, camPtr));
 
 			std::string imagePath = tmpImageDirectory+uFormat("/%d.jpg", viewId);
-
 			cv::imwrite(imagePath, imageRoi);
-
 			std::shared_ptr<sfmData::View> viewPtr = std::make_shared<sfmData::View>(
 					imagePath,
 					(IndexT)viewId,
@@ -2572,8 +2587,9 @@ bool multiBandTexturing(
 			sfmData.views.insert(std::make_pair((IndexT)viewId, viewPtr));
 			++viewId;
 		}
+		UDEBUG("camId=%d", camId);
 	}
-	UINFO("Temporary saving images in directory \"%s\"... done (%d images). %fs", tmpImageDirectory.c_str(), viewId, (int)cameraPoses.size(), timer.ticks());
+	UINFO("Temporary saving images in directory \"%s\"... done (%d images of %d nodes). %fs", tmpImageDirectory.c_str(), viewId, (int)cameraPoses.size(), timer.ticks());
 
 	mvsUtils::MultiViewParams mp(sfmData);
 
diff --git a/guilib/src/ExportCloudsDialog.cpp b/guilib/src/ExportCloudsDialog.cpp
index dab3a5093b..a860c2f2f2 100644
--- a/guilib/src/ExportCloudsDialog.cpp
+++ b/guilib/src/ExportCloudsDialog.cpp
@@ -4676,7 +4676,7 @@ void ExportCloudsDialog::saveTextureMeshes(
 								path.toStdString(),
 								mesh->cloud,
 								mesh->tex_polygons[0],
-								poses,
+								filterNodes(poses),
 								textureVertexToPixels,
 								images,
 								calibrations,