Core C++ library
Documentation is available over at Luxonis DepthAI API
DepthAI library doesn't yet provide API stability guarantees. While we take care to properly deprecate old functions, some changes might still be breaking. We expect to provide API stability from version 3.0.0 onwards.
- CMake >= 3.10
- C/C++14 compiler
- [optional] OpenCV 4 (required if building examples)
MacOS: Optional brew install opencv
Linux: Optional sudo apt install libopencv-dev
Make sure submodules are updated
git submodule update --init --recursive
Then configure and build
cmake -S. -Bbuild
cmake --build build
ℹ️ To speed up build times, use
cmake --build build --parallel [num CPU cores](CMake >= 3.12). For older versions use: Linux/macOS:cmake --build build -- -j[num CPU cores], MSVC:cmake --build build -- /MP[num CPU cores]
⚠️ If any CMake commands error withCMake Error: The source directory "" does not exist.replace argument-Swith-H
To build dynamic version of library configure with following option added
cmake -S. -Bbuild -D'BUILD_SHARED_LIBS=ON'
cmake --build build
Android is supported to some extent but not actively pursued nor tested. PRs with any improvements are welcome.
Steps:
- Install Android NDK (for example via Android Studio).
- Set the NDK path:
export ANDROID_HOME=$HOME/.local/lib/Android
export PATH=$PATH:$ANDROID_HOME/emulator:$ANDROID_HOME/platform-tools
export NDK=$ANDROID_HOME/ndk/23.1.7779620/ # Check version
- Ensure a recent version of cmake (apt version is outdated, install snap install cmake --classic)
- Run cmake, set your ABI and Platform as needed:
cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE=$NDK/build/cmake/android.toolchain.cmake -DANDROID_ABI=armeabi-v7a -DANDROID_PLATFORM=android-25
cmake --build build
To build the examples configure with following option added
cmake -S. -Bbuild -D'DEPTHAI_BUILD_EXAMPLES=ON'
cmake --build build
Then navigate to build/examples folder and run a preferred example
cd build/examples
./MobileNet/rgb_mobilenet
ℹ️ Multi-Config generators (like Visual Studio on Windows) will have the examples built in
build/examples/MobileNet/[Debug/Release/...]/rgb_mobilenet
Under releases you may find prebuilt library for Windows, for use in either integration method. See Releases
Targets available to link to are:
- depthai::core - Core library, without using opencv internally
- depthai::opencv - Core + support for opencv related helper functions (requires OpenCV4)
Build static or dynamic version of library (See: Building and optionally Installing)
Add find_package and target_link_libraries to your project
find_package(depthai CONFIG REQUIRED)
...
target_link_libraries([my-app] PRIVATE depthai::opencv)
And point CMake to either build directory or install directory:
-D'depthai_DIR=depthai-core/build'
or
-D'depthai_DIR=depthai-core/build/install/lib/cmake/depthai'
If library was installed to default search path like /usr/local on Linux, specifying depthai_DIR isn't necessary as CMake will find it automatically.
This method is more intrusive but simpler as it doesn't require building the library separately.
Add add_subdirectory which points to depthai-core folder before project command. Then link to any required targets.
add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/depthai-core EXCLUDE_FROM_ALL)
...
project(my-app)
...
target_link_libraries([my-app] PRIVATE depthai::opencv)
To integrate into a different build system than CMake, prefered way is compiling as dynamic library and setting correct build options.
- First build as dynamic library: Building Dynamic library
- Then install: Installing
In your non-CMake project (new Visual Studio project, ...)
- Set needed library directories:
build/install/lib(for linking to either depthai-core or depthai-opencv)build/install/bin(for .dll's)
- And include directories
build/install/include(library headers)build/install/include/depthai-shared/3rdparty(shared 3rdparty headers)build/install/lib/cmake/depthai/dependencies/include(dependency headers)
ℹ️ Threading library might need to be linked to explicitly.
ℹ️ Check
build/depthai-core-integration.txtorbuild/depthai-opencv-integration.txtfor up to date define options. The generated integration file also specifies include paths without requiring installation.
To install specify optional prefix and build target install
cmake -S. -Bbuild -D'CMAKE_INSTALL_PREFIX=[path/to/install/dir]'
cmake --build build --target install
If CMAKE_INSTALL_PREFIX isn't specified, the library is installed under build folder install.
The following environment variables can be set to alter default behavior of the library without having to recompile
| Environment variable | Description |
|---|---|
| DEPTHAI_LEVEL | Sets logging verbosity, 'trace', 'debug', 'warn', 'error' and 'off' |
| XLINK_LEVEL | Sets logging verbosity of XLink library, 'debug'. 'info', 'warn', 'error', 'fatal' and 'off' |
| DEPTHAI_INSTALL_SIGNAL_HANDLER | Set to 0 to disable installing Backward signal handler for stack trace printing |
| DEPTHAI_WATCHDOG | Sets device watchdog timeout. Useful for debugging (DEPTHAI_WATCHDOG=0), to prevent device reset while the process is paused. |
| DEPTHAI_WATCHDOG_INITIAL_DELAY | Specifies delay after which the device watchdog starts. |
| DEPTHAI_SEARCH_TIMEOUT | Specifies timeout in milliseconds for device searching in blocking functions. |
| DEPTHAI_CONNECT_TIMEOUT | Specifies timeout in milliseconds for establishing a connection to a given device. |
| DEPTHAI_BOOTUP_TIMEOUT | Specifies timeout in milliseconds for waiting the device to boot after sending the binary. |
| DEPTHAI_PROTOCOL | Restricts default search to the specified protocol. Options: any, usb, tcpip. |
| DEPTHAI_DEVICE_MXID_LIST | Restricts default search to the specified MXIDs. Accepts comma separated list of MXIDs. Lists filter results in an "AND" manner and not "OR" |
| DEPTHAI_DEVICE_ID_LIST | Alias to MXID list. Lists filter results in an "AND" manner and not "OR" |
| DEPTHAI_DEVICE_NAME_LIST | Restricts default search to the specified NAMEs. Accepts comma separated list of NAMEs. Lists filter results in an "AND" manner and not "OR" |
| DEPTHAI_DEVICE_BINARY | Overrides device Firmware binary. Mostly for internal debugging purposes. |
| DEPTHAI_BOOTLOADER_BINARY_USB | Overrides device USB Bootloader binary. Mostly for internal debugging purposes. |
| DEPTHAI_BOOTLOADER_BINARY_ETH | Overrides device Network Bootloader binary. Mostly for internal debugging purposes. |
| DEPTHAI_ALLOW_FACTORY_FLASHING | Internal use only |
To run the tests build the library with the following options
cmake -S. -Bbuild -D'DEPTHAI_TEST_EXAMPLES=ON' -D'DEPTHAI_BUILD_TESTS=ON' -D'DEPTHAI_BUILD_EXAMPLES=ON'
cmake --build build
Then navigate to build folder and run ctest with specified labels that denote device type to test on.
Currently available labels:
- usb
- poe
cd build
# Run tests on USB devices
ctest -L usb
# Run tests on PoE devices
ctest -L poe
The library uses clang format to enforce a certain coding style.
If a style check is failing, run the clangformat target, check the output and push changes.
To use this target clang format must be installed, preferably clang-format-10
sudo apt install clang-format-10
And to apply formatting
cmake --build build --target clangformat
Doxygen is used to generate documentation. Follow doxygen download and install the required binaries for your platform.
After that specify CMake define -D'DEPTHAI_BUILD_DOCS=ON' and build the target doxygen
Debugging can be done using Visual Studio Code and either GDB or LLDB (extension 'CodeLLDB').
LLDB in some cases was much faster to step with and resolved more incomplete_type variables than GDB. Your mileage may vary though.
If there is a need to step into Hunter libraries, that can be achieved by removing previous built artifacts
rm -r ~/.hunter
And configuring the project with the following CMake option set to ON
cmake . -D'HUNTER_KEEP_PACKAGE_SOURCES=ON'
This retains the libraries source code, so that debugger can step through it (the paths are already set up correctly)
If your build process happen to fail due to OpenCV library not being found, but you have the OpenCV installed, please
run build with additional -D'OpenCV_DIR=...' flag (replacing default Ubuntu path /usr/lib/x86_64-linux-gnu/cmake/opencv4 with yours)
cmake -S. -Bbuild -D'OpenCV_DIR=/usr/lib/x86_64-linux-gnu/cmake/opencv4'
Now the build process should correctly discover your OpenCV installation
Hunter is a CMake-only dependency manager for C/C++ projects.
If you are stuck with error message which mentions external libraries (subdirectory of .hunter) like the following:
/usr/bin/ld: /home/[user]/.hunter/_Base/062a19a/ccfed35/a84a713/Install/lib/liblzma.a(stream_flags_decoder.c.o): warning: relocation against `lzma_footer_magic' in read-only section `.text'
Try erasing the Hunter cache folder.
Linux/MacOS:
rm -r ~/.hunter
Windows:
del C:/.hunter
or
del C:/[user]/.hunter