Create albedo texture for a model from calibrated images (#6806)

Create an albedo for the triangle mesh using calibrated images. The triangle mesh must have texture coordinates (texture_uvs triangle attribute). This works by back projecting the images onto the texture surface. Overlapping images are blended together in the resulting albedo. For best results, use images captured with exposure and white balance lock to reduce the chance of seams in the output texture.

cpp/open3d/core/TensorKey.h

@@ -82,11 +82,11 @@ class TensorKey {
     /// For TensorKeyMode::Slice only.
     int64_t GetStart() const;
 
-    /// Get stop index. Throws exception if start is None.
+    /// Get stop index. Throws exception if stop is None.
     /// For TensorKeyMode::Slice only.
     int64_t GetStop() const;
 
-    /// Get step index. Throws exception if start is None.
+    /// Get step index. Throws exception if step is None.
     /// For TensorKeyMode::Slice only.
     int64_t GetStep() const;
 

cpp/open3d/io/ImageIO.cpp

@@ -81,7 +81,8 @@ bool WriteImage(const std::string &filename,
     auto map_itr = file_extension_to_image_write_function.find(filename_ext);
     if (map_itr == file_extension_to_image_write_function.end()) {
         utility::LogWarning(
-                "Write geometry::Image failed: unknown file extension.");
+                "Write geometry::Image failed: file extension {} unknown.",
+                filename_ext);
         return false;
     }
     return map_itr->second(filename, image, quality);

cpp/open3d/t/geometry/Image.cpp

@@ -156,6 +156,12 @@ Image Image::Resize(float sampling_rate, InterpType interp_type) const {
     if (sampling_rate == 1.0f) {
         return *this;
     }
+    if (GetDtype() == core::Bool) {  // Resize via UInt8
+        return Image(Image(data_.ReinterpretCast(core::UInt8))
+                             .Resize(sampling_rate, interp_type)
+                             .AsTensor()
+                             .ReinterpretCast(core::Bool));
+    }
 
     static const dtype_channels_pairs npp_supported{
             {core::UInt8, 1}, {core::UInt16, 1}, {core::Float32, 1},

cpp/open3d/t/geometry/RaycastingScene.cpp

@@ -1313,7 +1313,7 @@ uint32_t RaycastingScene::AddTriangles(const TriangleMesh& mesh) {
 }
 
 std::unordered_map<std::string, core::Tensor> RaycastingScene::CastRays(
-        const core::Tensor& rays, const int nthreads) {
+        const core::Tensor& rays, const int nthreads) const {
     AssertTensorDtypeLastDimDeviceMinNDim<float>(rays, "rays", 6,
                                                  impl_->tensor_device_);
     auto shape = rays.GetShape();
@@ -1723,7 +1723,6 @@ uint32_t RaycastingScene::INVALID_ID() { return RTC_INVALID_GEOMETRY_ID; }
 }  // namespace geometry
 }  // namespace t
 }  // namespace open3d
-
 namespace fmt {
 template <>
 struct formatter<RTCError> {

cpp/open3d/t/geometry/RaycastingScene.h

@@ -72,7 +72,7 @@ class RaycastingScene {
     ///         - \b primitive_normals A tensor with the normals of the hit
     ///           triangles. The shape is {.., 3}.
     std::unordered_map<std::string, core::Tensor> CastRays(
-            const core::Tensor &rays, const int nthreads = 0);
+            const core::Tensor &rays, const int nthreads = 0) const;
 
     /// \brief Checks if the rays have any intersection with the scene.
     /// \param rays A tensor with >=2 dims, shape {.., 6}, and Dtype Float32