Reduce installed Open3D wheel size

.github/workflows/macos.yml

@@ -183,9 +183,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: ${{ env.OPEN3D_ML_ROOT }}
 
       - name: Download build artifact
@@ -299,9 +296,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: ${{ env.OPEN3D_ML_ROOT }}
 
       - name: Download wheels

.github/workflows/ubuntu-wheel.yml

@@ -243,9 +243,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: ${{ env.OPEN3D_ML_ROOT }}
       - name: Download wheels
         uses: actions/download-artifact@v4

.github/workflows/ubuntu.yml

@@ -160,14 +160,16 @@ jobs:
           name: open3d-wheel-linux-x86_64
 
       - name: Checkout Open3D-ML
-        # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-        # requirements-torch.txt bump on ss/xpu is merged upstream.
-        run: git clone --depth 1 https://github.com/isl-org/Open3D-ML.git -b ss/xpu /tmp/Open3D-ML
+        uses: actions/checkout@v4
+        with:
+          repository: isl-org/Open3D-ML
+          # actions/checkout only accepts paths inside GITHUB_WORKSPACE.
+          path: open3d_ml
 
       - name: Install doc dependencies
         run: |
           source util/ci_utils.sh
-          install_docs_dependencies /tmp/Open3D-ML
+          install_docs_dependencies "${GITHUB_WORKSPACE}/open3d_ml"
 
       - name: Install Open3D wheel
         run: python -m pip install open3d*.whl

.github/workflows/windows.yml

@@ -119,9 +119,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: open3d_ml
 
       - name: Install PyTorch requirements
@@ -414,6 +411,8 @@ jobs:
       BUILD_CUDA_MODULE: ${{ matrix.device == 'cuda' && 'ON' || 'OFF' }}
       BUILD_SYCL_MODULE: ${{ matrix.device == 'xpu' && 'ON' || 'OFF' }}
       BUILD_PYTORCH_OPS: ${{ matrix.device == 'cuda' && 'OFF' || 'ON' }}
+      # Bundles the Open3D-ML models and pipelines when ML ops are built.
+      OPEN3D_ML_ROOT: ${{ github.workspace }}/open3d_ml
 
     steps:
 
@@ -437,9 +436,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: open3d_ml
 
       - name: Set up Python
@@ -642,9 +638,6 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: isl-org/Open3D-ML
-          # TODO(ss/sycl-mlops): switch back to main once the torch 2.13
-          # requirements-torch.txt bump on ss/xpu is merged upstream.
-          ref: ss/xpu
           path: open3d_ml
 
       - name: Download wheels
@@ -683,6 +676,11 @@ jobs:
           }
           echo "Installing Open3D wheel $PIP_PKG_NAME in virtual environment..."
           python -m pip install $PIP_PKG_NAME
+          # Wheels bundling Open3D-ML declare its Python dependencies as the
+          # `ml` extra, needed by the models, pipelines and datasets.
+          $bundlesML = python -c "import open3d; print(open3d._build_config['BUNDLE_OPEN3D_ML'])" |
+            Select-Object -Last 1
+          if ($bundlesML.Trim() -eq 'True') { python -m pip install "${PIP_PKG_NAME}[ml]" }
           python -c "import open3d; print('Imported:', open3d)"
           python -c "import open3d; print('CUDA enabled: ', open3d.core.cuda.is_available())"
           python -c "import open3d; print('SYCL enabled: ', open3d.core.sycl.is_available() if hasattr(open3d.core, 'sycl') else False)"

3rdparty/README_SYCL.md

@@ -111,6 +111,11 @@ with `oneapi-ci <https://github.com/oneapi-src/oneapi-ci/tree/0804a4c9281440d8a9
 User:
 - https://pypi.org/user/IntelAutomationEngineering/
 
+Linux import without sourcing oneAPI: `pip install -r python/requirements_sycl.txt`
+(transitive dpcpp-cpp-rt / onemkl-sycl-* DSOs land in `<venv>/lib`). With
+`BUILD_SYCL_MODULE`, extension RPATH (and wheel patchelf when available) points
+at `<Python prefix>/lib`.
+
 Libraries:
 - dpcpp-cpp-rt     https://pypi.org/project/dpcpp-cpp-rt/#history
 - mkl              https://pypi.org/project/mkl/#history

3rdparty/cmake/FindPytorch.cmake

@@ -18,6 +18,8 @@
 macro(translate_arch_string input output)
     if("${input}" MATCHES "[0-9]+-real")
         string(REGEX REPLACE "([1-9])([0-9])-real" "\\1.\\2" version "${input}")
+    elseif("${input}" MATCHES "[0-9]+-virtual")
+        string(REGEX REPLACE "([1-9])([0-9])-virtual" "\\1.\\2+PTX" version "${input}")
     elseif("${input}" MATCHES "([0-9]+)")
         string(REGEX REPLACE "([1-9])([0-9])" "\\1.\\2+PTX" version "${input}")
     elseif("${input}" STREQUAL "native")

CHANGELOG.md

@@ -1,4 +1,5 @@
 ## Main
+-   Reduce the installed size of the Open3D wheel: Open3D-ML Python dependencies are now an optional extra (`pip install open3d[ml]`, ~335 MB smaller for core-only installs) and `open3d.ml` submodules are imported lazily. Release CUDA wheels drop Turing (sm_75) SASS and ship compute_75 PTX instead. `BUNDLE_OPEN3D_ML` now defaults to ON when ML ops are built and `OPEN3D_ML_ROOT` is set, and Windows wheels bundle Open3D-ML too (PR #7540).
 -   Add symmetric ICP registration to the legacy and Tensor pipelines (PR #7276).
 -   Replace OpenMP with oneAPI TBB for all CPU parallelism; Open3D no longer depends on OpenMP. This removes the `libomp` / `libgomp` runtime dependency and the thread oversubscription and crashes caused by loading multiple OpenMP runtimes in one process (e.g. alongside PyTorch in Python). The `WITH_OPENMP` CMake option is removed, oneTBB >= 2021.4.0 is required, and `OMP_NUM_THREADS` is replaced by `open3d.utility.set_max_threads()` (C++: `utility::SetMaxThreads()` or a `tbb::task_arena`). `utility::OMPProgressBar` is removed in favor of the thread-safe `utility::ProgressBar`; `utility::GetThreadNum()` and `utility::InParallel()` are removed (PR #6626) (issues #6196, #6544, #6750)
 -   Add point cloud smoothing algorithms: Moving Least Squares (MLS), Laplacian, Taubin, and bilateral smoothing. These methods provide flexible noise reduction for point clouds with different preservation characteristics (PR #7419).

CMakeLists.txt

@@ -207,7 +207,21 @@ option(BUILD_AZURE_KINECT         "Build support for Azure Kinect sensor"    OFF
 # ML library options
 option(BUILD_TENSORFLOW_OPS       "Build ops for TensorFlow"                 OFF)
 option(BUILD_PYTORCH_OPS          "Build ops for PyTorch"                    OFF)
-option(BUNDLE_OPEN3D_ML           "Includes the Open3D-ML repo in the wheel" OFF)
+if(BUILD_TENSORFLOW_OPS OR BUILD_PYTORCH_OPS)
+    find_path(
+        OPEN3D_ML_ROOT
+        NAMES set_open3d_ml_root.sh
+        HINTS $ENV{OPEN3D_ML_ROOT}
+        DOC "Path to the Open3D-ML repo, bundled in the wheel when ML ops are built. May also be set as an env var."
+        NO_DEFAULT_PATH
+    )
+endif()
+if(OPEN3D_ML_ROOT AND (BUILD_TENSORFLOW_OPS OR BUILD_PYTORCH_OPS))
+    set(BUNDLE_OPEN3D_ML_DEFAULT ON)
+else()
+    set(BUNDLE_OPEN3D_ML_DEFAULT OFF)
+endif()
+option(BUNDLE_OPEN3D_ML "Includes the Open3D-ML repo in the wheel. Defaults to ON when ML ops are built and OPEN3D_ML_ROOT is set." ${BUNDLE_OPEN3D_ML_DEFAULT})
 
 # Build Python bindings (and optional ML ops) against an installed Open3D
 # devel package via find_package(Open3D). Skips compiling the C++ core and
@@ -294,6 +308,9 @@ endif()
 if(BUNDLE_OPEN3D_ML AND NOT (BUILD_TENSORFLOW_OPS OR BUILD_PYTORCH_OPS))
     message(SEND_ERROR "3DML depends on TensorFlow or PyTorch Ops. Enable them with -DBUILD_TENSORFLOW_OPS=ON or -DBUILD_PYTORCH_OPS=ON")
 endif()
+if(BUNDLE_OPEN3D_ML AND NOT OPEN3D_ML_ROOT)
+    message(SEND_ERROR "BUNDLE_OPEN3D_ML=ON requires OPEN3D_ML_ROOT to point to the Open3D-ML repo. Set -DOPEN3D_ML_ROOT=<path> or the env var with the same name.")
+endif()
 if(BUILD_WEBRTC AND LINUX_AARCH64)
     message(FATAL_ERROR "BUILD_WEBRTC=ON is not yet supported on ARM Linux")
 endif()
@@ -501,7 +518,12 @@ if(BUILD_CUDA_MODULE)
             # https://docs.nvidia.com/cuda/ampere-compatibility-guide/index.html#application-compatibility-on-ampere
             # https://en.wikipedia.org/wiki/CUDA#GPUs_supported
             find_package(CUDAToolkit REQUIRED)
-            if(CUDAToolkit_VERSION VERSION_GREATER_EQUAL "11.8")
+            if(CUDAToolkit_VERSION VERSION_GREATER_EQUAL "12.6")
+                # CUDA 12.6+ release wheels: SASS for Ampere..Hopper, compute_75 PTX
+                # so Turing (T4, RTX 20xx) still runs via JIT without shipping its
+                # SASS, and compute_90 PTX for forward compatibility.
+                set(CMAKE_CUDA_ARCHITECTURES 75-virtual 80-real 86-real 89-real 90)
+            elseif(CUDAToolkit_VERSION VERSION_GREATER_EQUAL "11.8")
                 set(CMAKE_CUDA_ARCHITECTURES 75-real 80-real 86-real 89-real 90)    # Turing, Ampere, Ada Lovelace, Hopper
             elseif(CUDAToolkit_VERSION VERSION_GREATER_EQUAL "11.1")
                 set(CMAKE_CUDA_ARCHITECTURES 70-real 75-real 80-real 86)            # Volta, Turing, Ampere

cmake/Open3DPrintConfigurationSummary.cmake

@@ -20,6 +20,10 @@ function(open3d_print_configuration_summary)
     open3d_aligned_print("CUDA Support" "${BUILD_CUDA_MODULE}")
     if(BUILD_CUDA_MODULE)
         open3d_aligned_print("CUDA cached memory manager" "${ENABLE_CACHED_CUDA_MANAGER}")
+        open3d_aligned_print("BUILD_COMMON_CUDA_ARCHS" "${BUILD_COMMON_CUDA_ARCHS}")
+        if(CMAKE_CUDA_ARCHITECTURES)
+            open3d_aligned_print("CMAKE_CUDA_ARCHITECTURES" "${CMAKE_CUDA_ARCHITECTURES}")
+        endif()
     endif()
     open3d_aligned_print("SYCL Support" "${BUILD_SYCL_MODULE}")
     if(ENABLE_SYCL_UNIFIED_SHARED_MEMORY)

cpp/pybind/CMakeLists.txt

@@ -103,9 +103,9 @@ if (BUILD_SHARED_LIBS)
             $<TARGET_FILE:Open3D::Open3D> $<TARGET_FILE_DIR:pybind>/${_libopen3d_soname}
     )
 endif()
-# Include additional libraries that may be absent from the user system
-# eg: libc++.so, libc++abi.so (needed by filament) for Linux.
-# libc++.so is a linker script including libc++.so.1 and libc++abi.so, so append 1 to libc++.so
+# Include additional libraries that may be absent from the user system (TBB).
+# Linux GUI wheels bundle LLVM libc++/libc++abi via ldd in
+# package_linux_wheel_runtime.sh (see make_python_package.cmake).
 # Prefer TBB::tbb; fall back to Open3D::tbb from an installed devel package.
 if (TARGET TBB::tbb)
     set(PYTHON_EXTRA_LIBRARIES $<TARGET_FILE:TBB::tbb>)
@@ -114,11 +114,6 @@ elseif (TARGET Open3D::tbb)
 else()
     message(FATAL_ERROR "TBB target required to package Python wheel extras")
 endif()
-if (BUILD_GUI AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
-    if (CPP_LIBRARY AND CPPABI_LIBRARY)
-        list(APPEND PYTHON_EXTRA_LIBRARIES ${CPP_LIBRARY}.1 ${CPPABI_LIBRARY})
-    endif()
-endif()
 # Note: Open3D no longer links libomp. TBB (packaged above via
 # PYTHON_EXTRA_LIBRARIES) is the only threading runtime shipped in the wheel,
 # which avoids the multiple-OpenMP-runtime crashes seen when another Python
@@ -178,15 +173,8 @@ if (BUILD_PYTORCH_OPS)
 endif()
 
 if (BUNDLE_OPEN3D_ML)
-    find_path(
-        OPEN3D_ML_ROOT
-        NAMES set_open3d_ml_root.sh
-        HINTS $ENV{OPEN3D_ML_ROOT}
-        DOC "Path to the Open3D-ML repo. This should be set if BUNDLE_OPEN3D_ML is enabled. Alternatively set an env var with the same name to populate this var."
-        REQUIRED
-        NO_DEFAULT_PATH
-    )
-
+    # OPEN3D_ML_ROOT is located in the top level CMakeLists.txt, which also
+    # decides whether Open3D-ML can be bundled.
     ExternalProject_Add(
         open3d_ml
         PREFIX "${CMAKE_BINARY_DIR}/open3d_ml"

cpp/pybind/make_python_package.cmake

@@ -23,8 +23,8 @@ foreach(COMPILED_MODULE_PATH ${COMPILED_MODULE_PATH_LIST})
          DESTINATION ${PYTHON_PACKAGE_DST_DIR}/open3d/
          FOLLOW_SYMLINK_CHAIN)
 endforeach()
-# Include additional libraries that may be absent from the user system
-# eg: libc++.so and libc++abi.so (needed by filament)
+# Include additional libraries that may be absent from the user system (e.g. TBB).
+# Linux LLVM libc++ for Filament is bundled separately via ldd; see below.
 # The linker recognizes only library.so.MAJOR, so remove .MINOR from the filename
 foreach(PYTHON_EXTRA_LIB ${PYTHON_EXTRA_LIBRARIES})
     get_filename_component(PYTHON_EXTRA_LIB_REAL ${PYTHON_EXTRA_LIB} REALPATH)
@@ -37,7 +37,33 @@ foreach(PYTHON_EXTRA_LIB ${PYTHON_EXTRA_LIBRARIES})
     configure_file(${PYTHON_EXTRA_LIB_REAL} ${PYTHON_PACKAGE_DST_DIR}/open3d/${SO_1_NAME} COPYONLY)
 endforeach()
 
+# Linux GUI: bundle LLVM libc++/libc++abi (and libunwind if linked) via ldd.
+# Shared builds ship libOpen3D; static builds link Filament into the pybind
+# extension instead, so fall back to that as the ELF to probe.
+if(BUILD_GUI AND UNIX AND NOT APPLE)
+    file(GLOB _libopen3d_probe LIST_DIRECTORIES false
+        "${PYTHON_PACKAGE_DST_DIR}/open3d/libOpen3D.so.*")
+    if(NOT _libopen3d_probe)
+        file(GLOB _libopen3d_probe LIST_DIRECTORIES false
+            "${PYTHON_PACKAGE_DST_DIR}/open3d/pybind*.so")
+    endif()
+    if(_libopen3d_probe)
+        list(GET _libopen3d_probe 0 _libopen3d_probe)
+        execute_process(
+            COMMAND bash "${CMAKE_CURRENT_LIST_DIR}/package_linux_wheel_runtime.sh"
+                "${PYTHON_PACKAGE_DST_DIR}/open3d" "${_libopen3d_probe}"
+            COMMAND_ERROR_IS_FATAL ANY
+        )
+    else()
+        message(WARNING "No ELF found in the Python package to probe for libc++")
+    endif()
+endif()
+
 # 3) Configured files and supporting files
+if(BUNDLE_OPEN3D_ML AND OPEN3D_ML_ROOT AND EXISTS "${OPEN3D_ML_ROOT}/requirements.txt")
+    configure_file("${OPEN3D_ML_ROOT}/requirements.txt"
+                   "${PYTHON_PACKAGE_DST_DIR}/requirements_ml.txt" COPYONLY)
+endif()
 configure_file("${PYTHON_PACKAGE_SRC_DIR}/setup.py"
                "${PYTHON_PACKAGE_DST_DIR}/setup.py")
 configure_file("${PYTHON_PACKAGE_SRC_DIR}/open3d/__init__.py"

cpp/pybind/package_linux_wheel_runtime.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+# Usage: package_linux_wheel_runtime.sh DEST_DIR PROBE_ELF (e.g. libOpen3D.so.N)
+# Copies Filament's LLVM libc++ runtime into the wheel under its DT_NEEDED name,
+# which is what $ORIGIN lookup uses at import time (e.g. libc++.so.1.0.20).
+set -euo pipefail
+dest=$1; elf=$2
+export LD_LIBRARY_PATH="$dest${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
+ldd "$elf" | awk '/libc\+\+|libunwind/ && $3 != "" {print $1, $3}' |
+  while read -r soname path; do
+    [ "$path" -ef "$dest/$soname" ] || cp -L "$path" "$dest/$soname"
+  done

docker/Dockerfile.ci

@@ -145,13 +145,10 @@ RUN ccache --version \
 # Checkout Open3D-ML main branch
 # TODO: We may add support for local Open3D-ML repo or pinned ML repo tag
 # Install Open3D-ML if it is not already present in BASE_IMAGE.
-# TODO(ss/sycl-mlops): switch back to main once requirements-torch-xpu.txt on
-# ss/xpu is merged upstream.
 ENV OPEN3D_ML_ROOT=/root/Open3D-ML
-RUN if [ "${BUILD_SYCL_MODULE}" = "ON" ]; then OPEN3D_ML_REF=ss/xpu; else OPEN3D_ML_REF=main; fi \
- && if [ ! -d "${OPEN3D_ML_ROOT}/.git" ]; then \
+RUN if [ ! -d "${OPEN3D_ML_ROOT}/.git" ]; then \
         git clone --depth 1 https://github.com/isl-org/Open3D-ML.git \
-            -b "${OPEN3D_ML_REF}" ${OPEN3D_ML_ROOT}; \
+            ${OPEN3D_ML_ROOT}; \
     fi
 
 # Open3D repo
@@ -171,6 +168,9 @@ RUN source util/ci_utils.sh \
     else \
         install_python_dependencies with-jupyter; \
     fi \
+ && if [ "${BUILD_TENSORFLOW_OPS}" = "ON" ] || [ "${BUILD_PYTORCH_OPS}" = "ON" ]; then \
+        install_open3d_ml_python_requirements; \
+    fi \
  && pip install -r python/requirements_test.txt \
  && install_nodejs_linux
 
@@ -185,6 +185,9 @@ RUN \
         export CMAKE_C_COMPILER=gcc; \
         export BUILD_ISPC_MODULE=ON; \
     fi \
+ && if [ "${BUILD_TENSORFLOW_OPS}" = "ON" ] || [ "${BUILD_PYTORCH_OPS}" = "ON" ]; then \
+        git -C "${OPEN3D_ML_ROOT}" checkout -b main || true; \
+    fi \
  && mkdir -p build \
  && cd build \
  && cmake --fresh -DBUILD_SHARED_LIBS=${BUILD_SHARED_LIBS} \

docs/arm.rst

@@ -174,7 +174,7 @@ Compiling Open3D on ARM64 macOS
 
     # Configure and choose build options
     cd Open3D && mkdir build && cd build
-    cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_TENSORFLOW_OPS=ON -DBUILD_PYTORCH_OPS=ON -DBUNDLE_OPEN3D_ML=ON ..
+    cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_TENSORFLOW_OPS=ON -DBUILD_PYTORCH_OPS=ON ..
 
     # Build
     make pip-package -j8    # Build Python wheel

docs/compilation.rst

@@ -332,11 +332,18 @@ ML Module
 The ML module consists of primitives like operators and layers as well as high
 level code for models and pipelines. To build the operators and layers, set
 ``BUILD_PYTORCH_OPS=ON`` and/or ``BUILD_TENSORFLOW_OPS=ON``.  Don't forget to also
-enable ``BUILD_CUDA_MODULE=ON`` for GPU support. To include the models and
-pipelines from Open3D-ML in the python package, set ``BUNDLE_OPEN3D_ML=ON`` and
-``OPEN3D_ML_ROOT`` to the Open3D-ML repository. You can directly download
-Open3D-ML from GitHub during the build with
-``OPEN3D_ML_ROOT=https://github.com/isl-org/Open3D-ML.git``.
+enable ``BUILD_CUDA_MODULE=ON`` for GPU support. Set ``OPEN3D_ML_ROOT`` to the
+Open3D-ML repository to also bundle its models and pipelines into the Python
+package: this is the default (``BUNDLE_OPEN3D_ML=ON``) whenever ML ops are built
+and ``OPEN3D_ML_ROOT`` is available. You can directly download Open3D-ML from
+GitHub during the build with
+``OPEN3D_ML_ROOT=https://github.com/isl-org/Open3D-ML.git``. To build only the
+ops and layers, e.g. when developing against a local Open3D-ML checkout, set
+``BUNDLE_OPEN3D_ML=OFF``.
+
+.. note:: The Python dependencies of Open3D-ML (PyYAML, scikit-learn, pandas,
+    matplotlib, ...) are not installed with the wheel. Users of the bundled ML
+    code install them with the ``ml`` extra, e.g. ``pip install open3d[ml]``.
 
 .. warning:: Compiling PyTorch ops with PyTorch < 1.9 may have
     stability issues. See `Open3D issue #3324 <https://github.com/isl-org/Open3D/issues/3324>`_
@@ -361,7 +368,6 @@ for all supported ML frameworks and bundling the high level Open3D-ML code.
           -DGLIBCXX_USE_CXX11_ABI=OFF \
           -DBUILD_PYTORCH_OPS=ON \
           -DBUILD_TENSORFLOW_OPS=ON \
-          -DBUNDLE_OPEN3D_ML=ON \
           -DOPEN3D_ML_ROOT=https://github.com/isl-org/Open3D-ML.git \
           ..
     # Install the python wheel with pip

docs/getting_started.in.rst

@@ -74,6 +74,16 @@ Pip (PyPI)
     pip install open3d        # or
     pip install open3d-cpu    # Smaller CPU only wheel on x86_64 Linux (since v0.17+)
 
+.. note::
+
+   The Open3D-ML models and pipelines (``open3d.ml.torch``, ``open3d.ml.tf``)
+   need additional Python packages, which are not installed by default. Install
+   them with the ``ml`` extra:
+
+   .. code-block:: bash
+
+        pip install open3d[ml]        # or open3d-cpu[ml] / open3d-xpu[ml]
+
 .. note::
 
    On Windows, ``open3d`` is the CPU wheel; ``pip install open3d-cuda`` and