ML 映像分类 连接器

import logging
from threading import Timer

import numpy as np

import greengrass_machine_learning_sdk as ml

# We assume the inference input image is provided as a local file
# to this inference client Lambda function.
with open('/test_img/test.jpg', 'rb') as f:
    content = f.read()

client = ml.client('inference')

def infer():
    logging.info('invoking Greengrass ML Inference service')

    try:
        resp = client.invoke_inference_service(
            AlgoType='image-classification',
            ServiceName='imageClassification',
            ContentType='image/jpeg',
            Body=content
        )
    except ml.GreengrassInferenceException as e:
        logging.info('inference exception {}("{}")'.format(e.__class__.__name__, e))
        return
    except ml.GreengrassDependencyException as e:
        logging.info('dependency exception {}("{}")'.format(e.__class__.__name__, e))
        return

    logging.info('resp: {}'.format(resp))
    predictions = resp['Body'].read()
    logging.info('predictions: {}'.format(predictions))
    
    # The connector output is in the format: [0.3,0.1,0.04,...]
    # Remove the '[' and ']' at the beginning and end.
    predictions = predictions[1:-1]
    count = len(predictions.split(','))
    predictions_arr = np.fromstring(predictions, count=count, sep=',')

    # Perform business logic that relies on the predictions_arr, which is an array
    # of probabilities.
    
    # Schedule the infer() function to run again in one second.
    Timer(1, infer).start()
    return

infer()

def function_handler(event, context):
    return

1. 将以下安装脚本的副本保存到核心设备上一个名为 x86_64.sh 的文件。

   Python 3.7Python 2.7

   Python 3.7

   #!/bin/bash
   set -e
   
   echo "Installing dependencies on the system..."
   
   release=$(awk -F= '/^NAME/{print $2}' /etc/os-release)
   
   if [ "$release" == '"Ubuntu"' ]; then
     # Ubuntu. Supports EC2 and DeepLens. DeepLens has all the dependencies installed, so
     # this is mostly to prepare dependencies on Ubuntu EC2 instance.
     apt-get -y update
     apt-get -y dist-upgrade
   
     apt-get install -y libgfortran3 libsm6 libxext6 libxrender1
     apt-get install -y python3.7 python3.7-dev
   elif [ "$release" == '"Amazon Linux"' ]; then
     # Amazon Linux. Expect python to be installed already
     yum -y update
     yum -y upgrade
   
     yum install -y compat-gcc-48-libgfortran libSM libXrender libXext
   else
     echo "OS Release not supported: $release"
     exit 1
   fi
   
   python3.7 -m pip install --upgrade pip
   python3.7 -m pip install numpy==1.15.0
   python3.7 -m pip install opencv-python || echo 'Error: Unable to install OpenCV with pip on this platform. Try building the latest OpenCV from source (https://github.com/opencv/opencv).'
   
   echo 'Dependency installation/upgrade complete.'

   注意

   如果 OpenCV 使用此脚本无法成功安装，您可以尝试从源代码进行构建。有关更多信息，请参阅 OpenCV 文档中的在 Linux 中安装，或参考您平台的其他在线资源。

   Python 2.7

   #!/bin/bash
   set -e
   
   echo "Installing MXNet dependencies on the system..."
   
   release=$(awk -F= '/^NAME/{print $2}' /etc/os-release)
   
   if [ "$release" == '"Ubuntu"' ]; then
     # Ubuntu. Supports EC2 and DeepLens. DeepLens has all the dependencies installed, so
     # this is mostly to prepare dependencies on Ubuntu EC2 instance.
     apt-get -y update
     apt-get -y dist-upgrade
   
     apt-get install -y libgfortran3 libsm6 libxext6 libxrender1 python-dev python-pip
   elif [ "$release" == '"Amazon Linux"' ]; then
     # Amazon Linux. Expect python to be installed already
     yum -y update
     yum -y upgrade
   
     yum install -y compat-gcc-48-libgfortran libSM libXrender libXext python-pip
   else
     echo "OS Release not supported: $release"
     exit 1
   fi
   
   pip install numpy==1.15.0 scipy opencv-python
   
   echo 'Dependency installation/upgrade complete.'

2. 从保存文件的目录中，键入以下命令：

   sudo x86_64.sh

1. 将以下安装脚本的副本保存到核心设备上一个名为 armv7l.sh 的文件。

   Python 3.7Python 2.7

   Python 3.7

   #!/bin/bash
   set -e
   
   echo "Installing dependencies on the system..."
   
   apt-get update
   apt-get -y upgrade
   
   apt-get install -y liblapack3 libopenblas-dev liblapack-dev
   apt-get install -y python3.7 python3.7-dev
   
   python3.7 -m pip install --upgrade pip
   python3.7 -m pip install numpy==1.15.0
   python3.7 -m pip install opencv-python || echo 'Error: Unable to install OpenCV with pip on this platform. Try building the latest OpenCV from source (https://github.com/opencv/opencv).'
   
   echo 'Dependency installation/upgrade complete.'

   注意

   如果 OpenCV 使用此脚本无法成功安装，您可以尝试从源代码进行构建。有关更多信息，请参阅 OpenCV 文档中的在 Linux 中安装，或参考您平台的其他在线资源。

   Python 2.7

   #!/bin/bash
   set -e
   
   echo "Installing MXNet dependencies on the system..."
   
   apt-get update
   apt-get -y upgrade
   
   apt-get install -y liblapack3 libopenblas-dev liblapack-dev python-dev
   
   # python-opencv depends on python-numpy. The latest version in the APT repository is python-numpy-1.8.2
   # This script installs python-numpy first so that python-opencv can be installed, and then install the latest
   # numpy-1.15.x with pip
   apt-get install -y python-numpy python-opencv
   dpkg --remove --force-depends python-numpy
   
   echo 'Install latest pip...'
   wget https://bootstrap.pypa.io/get-pip.py
   python get-pip.py
   rm get-pip.py
   
   pip install --upgrade numpy==1.15.0 picamera scipy
   
   echo 'Dependency installation/upgrade complete.'

2. 从保存文件的目录中，键入以下命令：

   sudo bash armv7l.sh

   注意

   在 Raspberry Pi 上，使用 pip 安装机器学习依赖项是一项内存密集型操作，可能会导致设备用尽内存，变得无法响应。解决办法是临时增加交换空间大小：

   在 /etc/dphys-swapfile 中，增加 CONF_SWAPSIZE 变量的值，然后运行以下命令重启 dphys-swapfile。

   /etc/init.d/dphys-swapfile restart