parthagar / depthai-python

Host-side DepthAI source code

DepthAI Python Library

Python bindings for C++ depthai-core library

Documentation

Documentation is available over at Luxonis DepthAI API

Installation

Prebuilt wheels are available in Luxonis repository Make sure pip is upgraded

python3 -m pip install -U pip
python3 -m pip install --extra-index-url https://artifacts.luxonis.com/artifactory/luxonis-python-snapshot-local/ depthai

Building from source

Dependencies

• cmake >= 3.4
• C++14 compiler (clang, gcc, msvc, ...)
• Python

Along these, dependencies of depthai-core are also required See: depthai-core dependencies

Building

To build a shared library from source perform the following:

mkdir build && cd build
cmake ..
cmake --build . --parallel

To build a wheel, execute the following

python3 -m pip wheel . -w wheelhouse

Tested platforms

• Windows 10
• Ubuntu 16.04, 18.04;
• Raspbian 10;
• macOS 10.14.6, 10.15.4;

Troubleshooting

Relocation link error

Build failure on Ubuntu 18.04 ("relocation ..." link error) with gcc 7.4.0 (default) - issue #3

• the solution was to upgrade gcc to version 8:

  sudo apt install g++-8
  sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-8 70
  sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-8 70
  

Hunter

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

LTO - link time optimization

If following message appears:

lto1: internal compiler error: in add_symbol_to_partition_1, at lto/lto-partition.c:152
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-10/README.Bugs> for instructions.
lto-wrapper: fatal error: /usr/bin/c++ returned 1 exit status
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/depthai.dir/build.make:227: depthai.cpython-38-x86_64-linux-gnu.so] Error 1
make[1]: *** [CMakeFiles/Makefile2:98: CMakeFiles/depthai.dir/all] Error 2
make: *** [Makefile:130: all] Error 2

One fix is to update linker: (In case you are on Ubuntu 20.04: /usr/bin/ld --version: 2.30)

# Add to the end of /etc/apt/sources.list:

echo "deb http://ro.archive.ubuntu.com/ubuntu groovy main" >> /etc/apt/sources.list

# Replace ro with your countries local cache server (check the content of the file to find out which is)
# Not mandatory, but faster

sudo apt update
sudo apt install binutils

# Should upgrade to 2.35.1
# Check version:
/usr/bin/ld --version
# Output should be: GNU ld (GNU Binutils for Ubuntu) 2.35.1
# Revert /etc/apt/sources.list to previous state (comment out line) to prevent updating other packages.
sudo apt update

Another option is to use clang compiler:

sudo apt install clang-10
mkdir build && cd build
CC=clang-10 CXX=clang++-10 cmake ..
cmake --build . --parallel