Embedded Linux (aarch64)

This page describes how to build sherpa-onnx for embedded Linux (aarch64, 64-bit) with cross-compiling on an x64 machine with Ubuntu OS.

Warning

By cross-compiling we mean that you do the compilation on a x86_64 machine. And you copy the generated binaries from a x86_64 machine and run them on an aarch64 machine.

If you want to compile sherpa-onnx on an aarch64 machine directly, please see Linux.

Note

You can download pre-compiled binaries for aarch64 from the following URL https://huggingface.co/csukuangfj/sherpa-onnx-libs/tree/main/aarch64

Please always download the latest version.

Example command to download the version 1.9.12:

# binaries built with shared libraries
wget https://huggingface.co/csukuangfj/sherpa-onnx-libs/resolve/main/aarch64/sherpa-onnx-v1.9.12-linux-aarch64-shared.tar.bz2

# binaries built with static link
wget https://huggingface.co/csukuangfj/sherpa-onnx-libs/resolve/main/aarch64/sherpa-onnx-v1.9.12-linux-aarch64-static.tar.bz2

# For users from China
# 中国国内用户，如果访问不了 huggingface, 请使用

# binaries built with shared libraries
wget https://hf-mirror.com/csukuangfj/sherpa-onnx-libs/resolve/main/aarch64/sherpa-onnx-v1.9.12-linux-aarch64-shared.tar.bz2

# binaries built with static link
wget https://hf-mirror.com/csukuangfj/sherpa-onnx-libs/resolve/main/aarch64/sherpa-onnx-v1.9.12-linux-aarch64-static.tar.bz2

Hint

We provide two colab notebooks for you to try this section step by step.

Build with shared libraries

Build with static libraries

build sherpa-onnx for aarch64 shared colab notebook

build sherpa-onnx for aarch64 static colab notebook

If you are using Windows/macOS or you don’t want to setup your local environment for cross-compiling, please use the above colab notebooks.

Install toolchain

The first step is to install a toolchain for cross-compiling.

Warning

You can use any toolchain that is suitable for your platform. The toolchain we use below is just an example.

Visit https://releases.linaro.org/components/toolchain/binaries/latest-7/aarch64-linux-gnu/

We are going to download gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu.tar.xz, which has been uploaded to https://huggingface.co/csukuangfj/sherpa-ncnn-toolchains.

Assume you want to install it in the folder $HOME/software:

mkdir -p $HOME/software
cd $HOME/software

# Note: the following toolchain gcc 7.5 is for building shared libraries.
# Please see below to use gcc 10 to build static libaries.
#
# You would get link errors if you use gcc 7.5 to build static libraries.
#
wget https://huggingface.co/csukuangfj/sherpa-ncnn-toolchains/resolve/main/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu.tar.xz

# For users from China
# 中国国内用户，如果访问不了 huggingface, 请使用
# wget https://hf-mirror.com/csukuangfj/sherpa-ncnn-toolchains/resolve/main/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu.tar.xz

tar xvf gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu.tar.xz

Next, we need to set the following environment variable:

export PATH=$HOME/software/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu/bin:$PATH

To check that we have installed the cross-compiling toolchain successfully, please run:

aarch64-linux-gnu-gcc --version

which should print the following log:

aarch64-linux-gnu-gcc (Linaro GCC 7.5-2019.12) 7.5.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Congratulations! You have successfully installed a toolchain for cross-compiling sherpa-onnx.

Build sherpa-onnx

Finally, let us build sherpa-onnx.

git clone https://github.com/k2-fsa/sherpa-onnx
cd sherpa-onnx
export BUILD_SHARED_LIBS=ON
./build-aarch64-linux-gnu.sh

After building, you will get two binaries:

sherpa-onnx$ ls -lh build-aarch64-linux-gnu/install/bin/
total 378K
-rwxr-xr-x 1 kuangfangjun root 187K Feb 21 21:55 sherpa-onnx
-rwxr-xr-x 1 kuangfangjun root 191K Feb 21 21:55 sherpa-onnx-alsa

Note

Please also copy the onnxruntime lib to your embedded systems and put it into the same directory as sherpa-onnx and sherpa-onnx-alsa.

sherpa-onnx$ ls -lh build-aarch64-linux-gnu/install/lib/*onnxruntime*
lrw-r--r-- 1 kuangfangjun root  24 Feb 21 21:38 build-aarch64-linux-gnu/install/lib/libonnxruntime.so -> libonnxruntime.so.1.14.0
-rw-r--r-- 1 kuangfangjun root 15M Feb 21 21:38 build-aarch64-linux-gnu/install/lib/libonnxruntime.so.1.14.0

That’s it!

Hint

  • sherpa-onnx is for decoding a single file

  • sherpa-onnx-alsa is for real-time speech recongition by reading the microphone with ALSA

sherpa-onnx-alsa

Caution

We recommend that you use sherpa-onnx-alsa on embedded systems such as Raspberry pi.

You need to provide a device_name when invoking sherpa-onnx-alsa. We describe below how to find the device name for your microphone.

Run the following command:

arecord -l

to list all avaliable microphones for recording. If it complains that arecord: command not found, please use sudo apt-get install alsa-utils to install it.

If the above command gives the following output:

**** List of CAPTURE Hardware Devices ****
card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

In this case, I only have 1 microphone. It is card 3 and that card has only device 0. To select card 3 and device 0 on that card, we need to pass plughw:3,0 to sherpa-onnx-alsa. (Note: It has the format plughw:card_number,device_index.)

For instance, you have to use

./sherpa-onnx-alsa \
  --encoder=./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/encoder-epoch-99-avg-1.onnx \
  --decoder=./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/decoder-epoch-99-avg-1.onnx \
  --joiner=./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/joiner-epoch-99-avg-1.onnx \
  --tokens=./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/tokens.txt \
  plughw:3,0

Please change the card number and also the device index on the selected card accordingly in your own situation. Otherwise, you won’t be able to record with your microphone.

Please read Pre-trained models for usages about the generated binaries.

Hint

If you want to select a pre-trained model for Raspberry that can be run on real-time, we recommend you to use Zipformer-transducer-based Models.

Please create an issue at https://github.com/k2-fsa/sherpa-onnx/issues if you have any problems.

How to build static libraries and static linked binaries

If you want to build static libraries and static linked binaries, please first download a cross compile toolchain with GCC >= 9.0. The following is an example:

mkdir -p $HOME/software
cd $HOME/software
wget -q https://huggingface.co/csukuangfj/sherpa-ncnn-toolchains/resolve/main/gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu.tar.xz

# For users from China
# 中国国内用户，如果访问不了 huggingface, 请使用
# wget -q https://hf-mirror.com/csukuangfj/sherpa-ncnn-toolchains/resolve/main/gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu.tar.xz

tar xf gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu.tar.xz

Next, we need to set the following environment variable:

export PATH=$HOME/software/gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu/bin:$PATH

To check that we have installed the cross-compiling toolchain successfully, please run:

aarch64-none-linux-gnu-gcc --version

which should print the following log:

aarch64-none-linux-gnu-gcc (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.3.1 20210621
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Now you can build static libraries and static linked binaries with the following commands:

git clone https://github.com/k2-fsa/sherpa-onnx
cd sherpa-onnx
export BUILD_SHARED_LIBS=OFF
./build-aarch64-linux-gnu.sh

You can use the following commands to check that the generated binaries are indeed static linked:

$ cd build-aarch64-linux-gnu/bin

$ ldd sherpa-onnx-alsa
    not a dynamic executable

$ readelf -d sherpa-onnx-alsa

Dynamic section at offset 0xed9950 contains 30 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libasound.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000000f (RPATH)              Library rpath: [$ORIGIN:/star-fj/fangjun/open-source/sherpa-onnx/build-aarch64-linux-gnu/_deps/onnxruntime-sr
c/lib:]
 0x000000000000000c (INIT)               0x404218