【python】pcDuino上面安装和测试SimpleCV以及OpenCV

土豆变薯条

pcDuino有计算能力来进行计算机视觉，这就让很多在Arduino 上不可能的项目可以在pcDuino上实现。 我们可以把计算机视觉这一非常强大的技术用在我们的项目中。 在这章，我们来看怎么安装和使用SimpleCV和OpenCV。
一：SimpleCV安装和例子
在我们开始动手之前，我们要确保手头有一个 UVC 兼容的USB摄像头。

下面为安装SimpleCV的步骤：
$sudo apt-get install ipython python-opencv python-scipy
python-numpy python-setuptools python-pip


$sudo pip install https://github.com/ingenuitas/SimpleCV/zipball/master


$sudo apt-get install python-pygame


$sudo apt-get install python-imaging

在终端里面输入 “$simpleCV” 就可以启动simpleCV. simpleCV是一个交互的命令解释器。 我们可以输入命令来执行：

    ubuntu@ubuntu:~$ simplecv
    +———————————————————–+
    SimpleCV 1.3.0 [interactive shell] - http://simplecv.org
    +———————————————————–+
    Commands:
    "exit()" or press "Ctrl+ D" to exit the shell
    "clear" to clear the shell screen
    "tutorial" to begin the SimpleCV interactive tutorial
    "example" gives a list of examples you can run
    "forums" will launch a web browser for the help forums
    "walkthrough" will launch a web browser with a walkthrough
    Usage:
    dot complete works to show library
    for example: Image().save("/tmp/test.jpg") will dot complete
    just by touching TAB after typing Image().
    Documentation:
    help(Image), ?Image, Image?, or Image()? all do the same
    "docs" will launch webbrowser showing documentation
    SimpleCV:1> cam=Camera()
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    VIDIOC_QUERYMENU: Invalid argument
    SimpleCV:2> img=cam.getImage()
    SimpleCV:3> img.show()
    SimpleCV:5:

以下为命令执行的结果：


二：OpenCV    安装和例子
OpenCV 是个开源的计算机视觉软件包。在这里我们详细的介绍如何安装OpenCV Python版本到pcDuino上面。 并且给出了两个例子，一个例子用来通过USB 摄像头来获取图形，另外一个例子通过OpenCV来做人脸识别。

安装步骤：

    $ sudo apt-get -y install build-essential cmake cmake-qt-gui pkg-config libpng12-0 libpng12-dev libpng++-dev libpng3 libpnglite-dev zlib1g-dbg zlib1g zlib1g-dev pngtools libtiff4-dev libtiff4 libtiffxx0c2 libtiff-tools
    $sudo apt-get -y install libjpeg8 libjpeg8-dev libjpeg8-dbg libjpeg-progs ffmpeg libavcodec-dev libavcodec53 libavformat53 libavformat-dev libgstreamer0.10-0-dbg libgstreamer0.10-0 libgstreamer0.10-dev libxine1-ffmpeg libxine-dev libxine1-bin libunicap2 libunicap2-dev libdc1394-22-dev libdc1394-22 libdc1394-utils swig libv4l-0 libv4l-dev python-numpy libpython2.6 python2.6-dev libgtk2.0-dev pkg-config
    $sudo apt-get install libopencv-dev python-opencv
    $sudo apt-get install python-dev
    $sudo ln -s /usr/lib/arm-linux-gnueabihf/libjpeg.so /usr/lib
    $sudo ln -s /usr/lib/arm-linux-gnueabihf/libfreetype.so /usr/lib
    $sudo ln -s /usr/lib/arm-linux-gnueabihf/libz.so /usr/lib
    $sudo easy_install PIL
    $sudo pip install -v PIL

例子1： 用OpenCV通过USB摄像头来抓图像：

    #!/Users/brent/.virtualenvs/lumber/bin/python
    import cv
    cv.NamedWindow("w1", cv.CV_WINDOW_AUTOSIZE)
    camera_index = 0
    capture = cv.CaptureFromCAM(camera_index)
    gx = gy = 1
    grayscale = blur = canny = False
    def repeat():
    global capture #declare as globals since we are assigning to them now
    global camera_index
    global gx, gy, grayscale, canny, blur
    frame = cv.QueryFrame(capture)
    # import pdb; pdb.set_trace()
    if grayscale:
    gray = cv.CreateImage(cv.GetSize(frame), frame.depth, 1)
    cv.CvtColor(frame, gray, cv.CV_RGB2GRAY)
    frame = gray
    if blur:
    g = cv.CreateImage(cv.GetSize(frame), cv.IPL_DEPTH_8U, frame.channels)
    cv.Smooth(frame, g, cv.CV_GAUSSIAN, gx, gy)
    frame = g
    if grayscale and canny:
    c = cv.CreateImage(cv.GetSize(frame), frame.depth, frame.channels)
    cv.Canny(frame, c, 10, 100, 3)
    frame = c
    cv.ShowImage("w1", frame)
    c = cv.WaitKey(10)
    if c==ord('='): #in "n" key is pressed while the popup window is in focus
    gx += 2
    gy += 2
    elif c == ord('-'):
    gx = max(1, gx-2)
    gy = max(1, gy-2)
    elif c == ord('x'):
    gx += 2
    elif c == ord('X'):
    gx = max(1, gx-2)
    elif c == ord('q'):
    exit(0)
    elif c == ord('b'):
    blur = not blur
    elif c == ord('g'):
    grayscale = not grayscale
    elif c == ord('c'):
    canny = not canny
    while True:
    repeat()

例子二： 人脸识别
输入图像：