mediapipe/docs/getting_started/install.md
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---
layout: default
title: Installation
parent: Getting Started
nav_order: 6
---
# Installation
{: .no_toc }
1. TOC
{:toc}
---
Note: To interoperate with OpenCV, OpenCV 3.x to 4.1 are preferred. OpenCV
2.x currently works but interoperability support may be deprecated in the
future.
Note: If you plan to use TensorFlow calculators and example apps, there is a
known issue with gcc and g++ version 6.3 and 7.3. Please use other versions.
Note: To make Mediapipe work with TensorFlow, please set Python 3.7 as the
default Python version and install the Python "six" library by running `pip3
install --user six`.
## Installing on Debian and Ubuntu
1. Install Bazelisk.
Follow the official
[Bazel documentation](https://docs.bazel.build/versions/master/install-bazelisk.html)
to install Bazelisk.
2. Checkout MediaPipe repository.
```bash
$ cd $HOME
$ git clone -depth 1 https://github.com/google/mediapipe.git
# Change directory into MediaPipe root directory
$ cd mediapipe
```
3. Install OpenCV and FFmpeg.
**Option 1**. Use package manager tool to install the pre-compiled OpenCV
libraries. FFmpeg will be installed via `libopencv-video-dev`.
OS | OpenCV
-------------------- | ------
Debian 9 (stretch) | 2.4
Debian 10 (buster) | 3.2
Debian 11 (bullseye) | 4.5
Ubuntu 16.04 LTS | 2.4
Ubuntu 18.04 LTS | 3.2
Ubuntu 20.04 LTS | 4.2
Ubuntu 20.04 LTS | 4.2
Ubuntu 21.04 | 4.5
```bash
$ sudo apt-get install -y \
libopencv-core-dev \
libopencv-highgui-dev \
libopencv-calib3d-dev \
libopencv-features2d-dev \
libopencv-imgproc-dev \
libopencv-video-dev
```
MediaPipe's [`opencv_linux.BUILD`] and [`WORKSPACE`] are already configured
for OpenCV 2/3 and should work correctly on any architecture:
```bash
# WORKSPACE
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr",
)
# opencv_linux.BUILD for OpenCV 2/3 installed from Debian package
cc_library(
name = "opencv",
linkopts = [
"-l:libopencv_core.so",
"-l:libopencv_calib3d.so",
"-l:libopencv_features2d.so",
"-l:libopencv_highgui.so",
"-l:libopencv_imgcodecs.so",
"-l:libopencv_imgproc.so",
"-l:libopencv_video.so",
"-l:libopencv_videoio.so",
],
)
```
For OpenCV 4 you need to modify [`opencv_linux.BUILD`] taking into account
current architecture:
```bash
# WORKSPACE
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr",
)
# opencv_linux.BUILD for OpenCV 4 installed from Debian package
cc_library(
name = "opencv",
hdrs = glob([
# Uncomment according to your multiarch value (gcc -print-multiarch):
# "include/aarch64-linux-gnu/opencv4/opencv2/cvconfig.h",
# "include/arm-linux-gnueabihf/opencv4/opencv2/cvconfig.h",
# "include/x86_64-linux-gnu/opencv4/opencv2/cvconfig.h",
"include/opencv4/opencv2/**/*.h*",
]),
includes = [
# Uncomment according to your multiarch value (gcc -print-multiarch):
# "include/aarch64-linux-gnu/opencv4/",
# "include/arm-linux-gnueabihf/opencv4/",
# "include/x86_64-linux-gnu/opencv4/",
"include/opencv4/",
],
linkopts = [
"-l:libopencv_core.so",
"-l:libopencv_calib3d.so",
"-l:libopencv_features2d.so",
"-l:libopencv_highgui.so",
"-l:libopencv_imgcodecs.so",
"-l:libopencv_imgproc.so",
"-l:libopencv_video.so",
"-l:libopencv_videoio.so",
],
)
```
**Option 2**. Run [`setup_opencv.sh`] to automatically build OpenCV from
source and modify MediaPipe's OpenCV config. This option will do all steps
defined in Option 3 automatically.
**Option 3**. Follow OpenCV's
[documentation](https://docs.opencv.org/3.4.6/d7/d9f/tutorial_linux_install.html)
to manually build OpenCV from source code.
You may need to modify [`WORKSPACE`] and [`opencv_linux.BUILD`] to point
MediaPipe to your own OpenCV libraries. Assume OpenCV would be installed to
`/usr/local/` which is recommended by default.
OpenCV 2/3 setup:
```bash
# WORKSPACE
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr/local",
)
# opencv_linux.BUILD for OpenCV 2/3 installed to /usr/local
cc_library(
name = "opencv",
linkopts = [
"-L/usr/local/lib",
"-l:libopencv_core.so",
"-l:libopencv_calib3d.so",
"-l:libopencv_features2d.so",
"-l:libopencv_highgui.so",
"-l:libopencv_imgcodecs.so",
"-l:libopencv_imgproc.so",
"-l:libopencv_video.so",
"-l:libopencv_videoio.so",
],
)
```
OpenCV 4 setup:
```bash
# WORKSPACE
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr/local",
)
# opencv_linux.BUILD for OpenCV 4 installed to /usr/local
cc_library(
name = "opencv",
hdrs = glob([
"include/opencv4/opencv2/**/*.h*",
]),
includes = [
"include/opencv4/",
],
linkopts = [
"-L/usr/local/lib",
"-l:libopencv_core.so",
"-l:libopencv_calib3d.so",
"-l:libopencv_features2d.so",
"-l:libopencv_highgui.so",
"-l:libopencv_imgcodecs.so",
"-l:libopencv_imgproc.so",
"-l:libopencv_video.so",
"-l:libopencv_videoio.so",
],
)
```
Current FFmpeg setup is defined in [`ffmpeg_linux.BUILD`] and should work
for any architecture:
```bash
# WORKSPACE
new_local_repository(
name = "linux_ffmpeg",
build_file = "@//third_party:ffmpeg_linux.BUILD",
path = "/usr"
)
# ffmpeg_linux.BUILD for FFmpeg installed from Debian package
cc_library(
name = "libffmpeg",
linkopts = [
"-l:libavcodec.so",
"-l:libavformat.so",
"-l:libavutil.so",
],
)
```
4. For running desktop examples on Linux only (not on OS X) with GPU
acceleration.
```bash
# Requires a GPU with EGL driver support.
# Can use mesa GPU libraries for desktop, (or Nvidia/AMD equivalent).
sudo apt-get install mesa-common-dev libegl1-mesa-dev libgles2-mesa-dev
# To compile with GPU support, replace
--define MEDIAPIPE_DISABLE_GPU=1
# with
--copt -DMESA_EGL_NO_X11_HEADERS --copt -DEGL_NO_X11
# when building GPU examples.
```
5. Run the [Hello World! in C++ example](./hello_world_cpp.md).
```bash
$ export GLOG_logtostderr=1
# if you are running on Linux desktop with CPU only
$ bazel run --define MEDIAPIPE_DISABLE_GPU=1 \
mediapipe/examples/desktop/hello_world:hello_world
# If you are running on Linux desktop with GPU support enabled (via mesa drivers)
$ bazel run --copt -DMESA_EGL_NO_X11_HEADERS --copt -DEGL_NO_X11 \
mediapipe/examples/desktop/hello_world:hello_world
# Should print:
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
```
If you run into a build error, please read
[Troubleshooting](./troubleshooting.md) to find the solutions of several common
build issues.
## Installing on CentOS
**Disclaimer**: Running MediaPipe on CentOS is experimental.
1. Install Bazelisk.
Follow the official
[Bazel documentation](https://docs.bazel.build/versions/master/install-bazelisk.html)
to install Bazelisk.
2. Checkout MediaPipe repository.
```bash
$ git clone -depth 1 https://github.com/google/mediapipe.git
# Change directory into MediaPipe root directory
$ cd mediapipe
```
3. Install OpenCV.
Option 1. Use package manager tool to install the pre-compiled version.
Note: yum installs OpenCV 2.4.5, which may have an opencv/gstreamer
[issue](https://github.com/opencv/opencv/issues/4592).
```bash
$ sudo yum install opencv-devel
```
Option 2. Build OpenCV from source code.
Note: You may need to modify [`WORKSPACE`], [`opencv_linux.BUILD`] and
[`ffmpeg_linux.BUILD`] to point MediaPipe to your own OpenCV and FFmpeg
libraries. For example if OpenCV and FFmpeg are both manually installed in
"/usr/local/", you will need to update: (1) the "linux_opencv" and
"linux_ffmpeg" new_local_repository rules in [`WORKSPACE`], (2) the "opencv"
cc_library rule in [`opencv_linux.BUILD`], and (3) the "libffmpeg"
cc_library rule in [`ffmpeg_linux.BUILD`]. These 3 changes are shown below:
```bash
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr/local",
)
new_local_repository(
name = "linux_ffmpeg",
build_file = "@//third_party:ffmpeg_linux.BUILD",
path = "/usr/local",
)
cc_library(
name = "opencv",
srcs = glob(
[
"lib/libopencv_core.so",
"lib/libopencv_highgui.so",
"lib/libopencv_imgcodecs.so",
"lib/libopencv_imgproc.so",
"lib/libopencv_video.so",
"lib/libopencv_videoio.so",
],
),
hdrs = glob([
# For OpenCV 3.x
"include/opencv2/**/*.h*",
# For OpenCV 4.x
# "include/opencv4/opencv2/**/*.h*",
]),
includes = [
# For OpenCV 3.x
"include/",
# For OpenCV 4.x
# "include/opencv4/",
],
linkstatic = 1,
visibility = ["//visibility:public"],
)
cc_library(
name = "libffmpeg",
srcs = glob(
[
"lib/libav*.so",
],
),
hdrs = glob(["include/libav*/*.h"]),
includes = ["include"],
linkopts = [
"-lavcodec",
"-lavformat",
"-lavutil",
],
linkstatic = 1,
visibility = ["//visibility:public"],
)
```
4. Run the [Hello World! in C++ example](./hello_world_cpp.md).
```bash
$ export GLOG_logtostderr=1
# Need bazel flag 'MEDIAPIPE_DISABLE_GPU=1' if you are running on Linux desktop with CPU only
$ bazel run --define MEDIAPIPE_DISABLE_GPU=1 \
mediapipe/examples/desktop/hello_world:hello_world
# Should print:
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
```
If you run into a build error, please read
[Troubleshooting](./troubleshooting.md) to find the solutions of several common
build issues.
## Installing on macOS
1. Prework:
* Install [Homebrew](https://brew.sh).
* Install [Xcode](https://developer.apple.com/xcode/) and its Command Line
Tools by `xcode-select --install`.
2. Install Bazelisk.
Follow the official
[Bazel documentation](https://docs.bazel.build/versions/master/install-bazelisk.html)
to install Bazelisk.
3. Checkout MediaPipe repository.
```bash
$ git clone --depth 1 https://github.com/google/mediapipe.git
$ cd mediapipe
```
4. Install OpenCV and FFmpeg.
Option 1. Use HomeBrew package manager tool to install the pre-compiled
OpenCV 3 libraries. FFmpeg will be installed via OpenCV.
```bash
$ brew install opencv@3
# There is a known issue caused by the glog dependency. Uninstall glog.
$ brew uninstall --ignore-dependencies glog
```
Option 2. Use MacPorts package manager tool to install the OpenCV libraries.
```bash
$ port install opencv
```
Note: when using MacPorts, please edit the [`WORKSPACE`],
[`opencv_macos.BUILD`], and [`ffmpeg_macos.BUILD`] files like the following:
```bash
new_local_repository(
name = "macos_opencv",
build_file = "@//third_party:opencv_macos.BUILD",
path = "/opt",
)
new_local_repository(
name = "macos_ffmpeg",
build_file = "@//third_party:ffmpeg_macos.BUILD",
path = "/opt",
)
cc_library(
name = "opencv",
srcs = glob(
[
"local/lib/libopencv_core.dylib",
"local/lib/libopencv_highgui.dylib",
"local/lib/libopencv_imgcodecs.dylib",
"local/lib/libopencv_imgproc.dylib",
"local/lib/libopencv_video.dylib",
"local/lib/libopencv_videoio.dylib",
],
),
hdrs = glob(["local/include/opencv2/**/*.h*"]),
includes = ["local/include/"],
linkstatic = 1,
visibility = ["//visibility:public"],
)
cc_library(
name = "libffmpeg",
srcs = glob(
[
"local/lib/libav*.dylib",
],
),
hdrs = glob(["local/include/libav*/*.h"]),
includes = ["local/include/"],
linkopts = [
"-lavcodec",
"-lavformat",
"-lavutil",
],
linkstatic = 1,
visibility = ["//visibility:public"],
)
```
5. Make sure that Python 3 and the Python "six" library are installed.
```
$ brew install python
$ sudo ln -s -f /usr/local/bin/python3.7 /usr/local/bin/python
$ python --version
Python 3.7.4
$ pip3 install --user six
```
6. Run the [Hello World! in C++ example](./hello_world_cpp.md).
```bash
$ export GLOG_logtostderr=1
# Need bazel flag 'MEDIAPIPE_DISABLE_GPU=1' as desktop GPU is currently not supported
$ bazel run --define MEDIAPIPE_DISABLE_GPU=1 \
mediapipe/examples/desktop/hello_world:hello_world
# Should print:
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
```
If you run into a build error, please read
[Troubleshooting](./troubleshooting.md) to find the solutions of several common
build issues.
## Installing on Windows
**Disclaimer**: Running MediaPipe on Windows is experimental.
Note: building MediaPipe Android apps is still not possible on native
Windows. Please do this in WSL instead and see the WSL setup instruction in the
next section.
1. Install [MSYS2](https://www.msys2.org/) and edit the `%PATH%` environment
variable.
If MSYS2 is installed to `C:\msys64`, add `C:\msys64\usr\bin` to your
`%PATH%` environment variable.
2. Install necessary packages.
```
C:\> pacman -S git patch unzip
```
3. Install Python and allow the executable to edit the `%PATH%` environment
variable.
Download Python Windows executable from
https://www.python.org/downloads/windows/ and install.
4. Install Visual C++ Build Tools 2019 and WinSDK
Go to
[the VisualStudio website](https://visualstudio.microsoft.com/visual-cpp-build-tools),
download build tools, and install Microsoft Visual C++ 2019 Redistributable
and Microsoft Build Tools 2019.
Download the WinSDK from
[the official MicroSoft website](https://developer.microsoft.com/en-us/windows/downloads/windows-10-sdk/)
and install.
5. Install Bazel or Bazelisk and add the location of the Bazel executable to
the `%PATH%` environment variable.
Option 1. Follow
[the official Bazel documentation](https://docs.bazel.build/versions/master/install-windows.html)
to install Bazel 5.2.0 or higher.
Option 2. Follow the official
[Bazel documentation](https://docs.bazel.build/versions/master/install-bazelisk.html)
to install Bazelisk.
6. Set Bazel variables. Learn more details about
["Build on Windows"](https://docs.bazel.build/versions/master/windows.html#build-c-with-msvc)
in the Bazel official documentation.
```
# Please find the exact paths and version numbers from your local version.
C:\> set BAZEL_VS=C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools
C:\> set BAZEL_VC=C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC
C:\> set BAZEL_VC_FULL_VERSION=<Your local VC version>
C:\> set BAZEL_WINSDK_FULL_VERSION=<Your local WinSDK version>
```
7. Checkout MediaPipe repository.
```
C:\Users\Username\mediapipe_repo> git clone -depth 1 https://github.com/google/mediapipe.git
# Change directory into MediaPipe root directory
C:\Users\Username\mediapipe_repo> cd mediapipe
```
8. Install OpenCV.
Download the Windows executable from https://opencv.org/releases/ and
install. We currently use OpenCV 3.4.10. Remember to edit the [`WORKSPACE`]
file if OpenCV is not installed at `C:\opencv`.
```
new_local_repository(
name = "windows_opencv",
build_file = "@//third_party:opencv_windows.BUILD",
path = "C:\\<path to opencv>\\build",
)
```
9. Run the [Hello World! in C++ example](./hello_world_cpp.md).
Note: For building MediaPipe on Windows, please add `--action_env
PYTHON_BIN_PATH="C://path//to//python.exe"` to the build command.
Alternatively, you can follow
[issue 724](https://github.com/google/mediapipe/issues/724) to fix the
python configuration manually.
```
C:\Users\Username\mediapipe_repo>bazel build -c opt --define MEDIAPIPE_DISABLE_GPU=1 --action_env PYTHON_BIN_PATH="C://python_36//python.exe" mediapipe/examples/desktop/hello_world
C:\Users\Username\mediapipe_repo>set GLOG_logtostderr=1
C:\Users\Username\mediapipe_repo>bazel-bin\mediapipe\examples\desktop\hello_world\hello_world.exe
# should print:
# I20200514 20:43:12.277598 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.278597 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.279618 1200 hello_world.cc:56] Hello World!
# I20200514 20:43:12.280613 1200 hello_world.cc:56] Hello World!
```
If you run into a build error, please read
[Troubleshooting](./troubleshooting.md) to find the solutions of several common
build issues.
## Installing on Windows Subsystem for Linux (WSL)
Note: The pre-built OpenCV packages don't support cameras in WSL. Unless you
[compile](https://funvision.blogspot.com/2019/12/opencv-web-camera-and-video-streams-in.html)
OpenCV with FFMPEG and GStreamer in WSL, the live demos won't work with any
cameras. Alternatively, you use a video file as input.
1. Follow the
[instruction](https://docs.microsoft.com/en-us/windows/wsl/install-win10) to
install Windows Subsystem for Linux (Ubuntu).
2. Install Windows ADB and start the ADB server in Windows.
Note: Windows' and WSLs adb versions must be the same version, e.g., if WSL
has ADB 1.0.39, you need to download the corresponding Windows ADB from
[here](https://dl.google.com/android/repository/platform-tools_r30.0.3-windows.zip).
3. Launch WSL.
Note: All the following steps will be executed in WSL. The Windows directory
of the Linux Subsystem can be found in
C:\Users\YourUsername\AppData\Local\Packages\CanonicalGroupLimited.UbuntuonWindows_SomeID\LocalState\rootfs\home
4. Install the needed packages.
```bash
username@DESKTOP-TMVLBJ1:~$ sudo apt-get update && sudo apt-get install -y build-essential git python zip adb openjdk-8-jdk
```
5. Install Bazelisk.
Follow the official
[Bazel documentation](https://docs.bazel.build/versions/master/install-bazelisk.html)
to install Bazelisk.
6. Checkout MediaPipe repository.
```bash
username@DESKTOP-TMVLBJ1:~$ git clone -depth 1 https://github.com/google/mediapipe.git
username@DESKTOP-TMVLBJ1:~$ cd mediapipe
```
7. Install OpenCV and FFmpeg.
Option 1. Use package manager tool to install the pre-compiled OpenCV
libraries. FFmpeg will be installed via libopencv-video-dev.
```bash
username@DESKTOP-TMVLBJ1:~/mediapipe$ sudo apt-get install libopencv-core-dev libopencv-highgui-dev \
libopencv-calib3d-dev libopencv-features2d-dev \
libopencv-imgproc-dev libopencv-video-dev
```
Option 2. Run [`setup_opencv.sh`] to automatically build OpenCV from source
and modify MediaPipe's OpenCV config.
Option 3. Follow OpenCV's
[documentation](https://docs.opencv.org/3.4.6/d7/d9f/tutorial_linux_install.html)
to manually build OpenCV from source code.
Note: You may need to modify [`WORKSPACE`] and [`opencv_linux.BUILD`] to
point MediaPipe to your own OpenCV libraries, e.g., if OpenCV 4 is installed
in "/usr/local/", you need to update the "linux_opencv" new_local_repository
rule in [`WORKSPACE`] and "opencv" cc_library rule in [`opencv_linux.BUILD`]
like the following:
```bash
new_local_repository(
name = "linux_opencv",
build_file = "@//third_party:opencv_linux.BUILD",
path = "/usr/local",
)
cc_library(
name = "opencv",
srcs = glob(
[
"lib/libopencv_core.so",
"lib/libopencv_highgui.so",
"lib/libopencv_imgcodecs.so",
"lib/libopencv_imgproc.so",
"lib/libopencv_video.so",
"lib/libopencv_videoio.so",
],
),
hdrs = glob(["include/opencv4/**/*.h*"]),
includes = ["include/opencv4/"],
linkstatic = 1,
visibility = ["//visibility:public"],
)
```
8. Run the [Hello World! in C++ example](./hello_world_cpp.md).
```bash
username@DESKTOP-TMVLBJ1:~/mediapipe$ export GLOG_logtostderr=1
# Need bazel flag 'MEDIAPIPE_DISABLE_GPU=1' as desktop GPU is currently not supported
username@DESKTOP-TMVLBJ1:~/mediapipe$ bazel run --define MEDIAPIPE_DISABLE_GPU=1 \
mediapipe/examples/desktop/hello_world:hello_world
# Should print:
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
```
If you run into a build error, please
read [Troubleshooting](./troubleshooting.md) to find the solutions of several
common build issues.
## Installing using Docker
This will use a Docker image that will isolate mediapipe's installation from the rest of the system.
1. [Install Docker](https://docs.docker.com/install/#supported-platforms) on
your host system.
2. Build a docker image with tag "mediapipe".
```bash
$ git clone -depth 1 https://github.com/google/mediapipe.git
$ cd mediapipe
$ docker build --tag=mediapipe .
# Should print:
# Sending build context to Docker daemon 147.8MB
# Step 1/9 : FROM ubuntu:latest
# latest: Pulling from library/ubuntu
# 6abc03819f3e: Pull complete
# 05731e63f211: Pull complete
# ........
# See http://bazel.build/docs/getting-started.html to start a new project!
# Removing intermediate container 82901b5e79fa
# ---> f5d5f402071b
# Step 9/9 : COPY . /mediapipe/
# ---> a95c212089c5
# Successfully built a95c212089c5
# Successfully tagged mediapipe:latest
```
3. Run the [Hello World! in C++ example](./hello_world_cpp.md).
```bash
$ docker run -it --name mediapipe mediapipe:latest
root@bca08b91ff63:/mediapipe# GLOG_logtostderr=1 bazel run --define MEDIAPIPE_DISABLE_GPU=1 mediapipe/examples/desktop/hello_world
# Should print:
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
# Hello World!
```
If you run into a build error, please
read [Troubleshooting](./troubleshooting.md) to find the solutions of several
common build issues.
4. Build a MediaPipe Android example.
```bash
$ docker run -it --name mediapipe mediapipe:latest
root@bca08b91ff63:/mediapipe# bash ./setup_android_sdk_and_ndk.sh
# Should print:
# Android NDK is now installed. Consider setting $ANDROID_NDK_HOME environment variable to be /root/Android/Sdk/ndk-bundle/android-ndk-r19c
# Set android_ndk_repository and android_sdk_repository in WORKSPACE
# Done
root@bca08b91ff63:/mediapipe# bazel build -c opt --config=android_arm64 mediapipe/examples/android/src/java/com/google/mediapipe/apps/objectdetectiongpu:objectdetectiongpu
# Should print:
# Target //mediapipe/examples/android/src/java/com/google/mediapipe/apps/objectdetectiongpu:objectdetectiongpu up-to-date:
# bazel-bin/mediapipe/examples/android/src/java/com/google/mediapipe/apps/objectdetectiongpu/objectdetectiongpu_deploy.jar
# bazel-bin/mediapipe/examples/android/src/java/com/google/mediapipe/apps/objectdetectiongpu/objectdetectiongpu_unsigned.apk
# bazel-bin/mediapipe/examples/android/src/java/com/google/mediapipe/apps/objectdetectiongpu/objectdetectiongpu.apk
# INFO: Elapsed time: 144.462s, Critical Path: 79.47s
# INFO: 1958 processes: 1 local, 1863 processwrapper-sandbox, 94 worker.
# INFO: Build completed successfully, 2028 total actions
```
<!-- 5. Uncomment the last line of the Dockerfile
```bash
RUN bazel build -c opt --define MEDIAPIPE_DISABLE_GPU=1 mediapipe/examples/desktop/demo:object_detection_tensorflow_demo
```
and rebuild the image and then run the docker image
```bash
docker build --tag=mediapipe .
docker run -i -t mediapipe:latest
``` -->
[`WORKSPACE`]: https://github.com/google/mediapipe/blob/master/WORKSPACE
[`opencv_linux.BUILD`]: https://github.com/google/mediapipe/tree/master/third_party/opencv_linux.BUILD
[`ffmpeg_linux.BUILD`]:https://github.com/google/mediapipe/tree/master/third_party/ffmpeg_linux.BUILD
[`opencv_macos.BUILD`]: https://github.com/google/mediapipe/tree/master/third_party/opencv_macos.BUILD
[`ffmpeg_macos.BUILD`]:https://github.com/google/mediapipe/tree/master/third_party/ffmpeg_macos.BUILD
[`setup_opencv.sh`]: https://github.com/google/mediapipe/blob/master/setup_opencv.sh