游戏机摄像头不工作？

Question

这个剧本是用Face.com网站应用程序编程接口。由于某些原因，pygame找不到我的相机（我想这就是问题所在）。我的密码有问题吗？在

我已经安装了pygame，看起来工作得很好。但是下面的代码给了我错误。在

####################################################
#  IMPORTS
####################################################

# imports for capturing a frame from the webcam
import pygame
import pygame.camera
import pygame.image

# import for detecting faces in the photo
import face_client

# import for storing data
from pysqlite2 import dbapi2 as sqlite

# miscellaneous imports
from time import strftime, localtime, sleep
import os
import sys

####################################################
# CONSTANTS
####################################################

DB_FILE_PATH="log.db"
FACE_COM_APIKEY="API CODE"
FACE_COM_APISECRET="API SECRET"
DALELANE_FACETAG="name@name.name"
POLL_FREQUENCY_SECONDS=3

class AudienceMonitor():

    #
    # prepare the database where we store the results
    #
    def initialiseDB(self):
        self.connection = sqlite.connect(DB_FILE_PATH, detect_types=sqlite.PARSE_DECLTYPES|sqlite.PARSE_COLNAMES)
        cursor = self.connection.cursor()

        cursor.execute('SELECT name FROM sqlite_master WHERE type="table" AND NAME="facelog" ORDER BY name')
        if not cursor.fetchone():
            cursor.execute('CREATE TABLE facelog(ts timestamp unique default current_timestamp, isSmiling boolean, smilingConfidence int, mood text, moodConfidence int)')

        cursor.execute('SELECT name FROM sqlite_master WHERE type="table" AND NAME="guestlog" ORDER BY name')
        if not cursor.fetchone():
            cursor.execute('CREATE TABLE guestlog(ts timestamp unique default current_timestamp, isSmiling boolean, smilingConfidence int, mood text, moodConfidence int, agemin int, ageminConfidence int, agemax int, agemaxConfidence int, ageest int, ageestConfidence int, gender text, genderConfidence int)')

        self.connection.commit()

    #
    # initialise the camera
    #
    def prepareCamera(self):
        # prepare the webcam
        pygame.camera.init()
        self.camera = pygame.camera.Camera(pygame.camera.list_cameras()[0], (900, 675))
        self.camera.start()

    #
    # take a single frame and store in the path provided
    #
    def captureFrame(self, filepath):
        # save the picture
        image = self.camera.get_image()
        pygame.image.save(image, filepath)

    #
    # gets a string representing the current time to the nearest second
    #
    def getTimestampString(self):
        return strftime("%Y%m%d%H%M%S", localtime())

    #
    # get attribute from face detection response
    #
    def getFaceDetectionAttributeValue(self, face, attribute):
        value = None
        if attribute in face['attributes']:
            value = face['attributes'][attribute]['value']
        return value

    #
    # get confidence from face detection response
    #
    def getFaceDetectionAttributeConfidence(self, face, attribute):
        confidence = None
        if attribute in face['attributes']:
            confidence = face['attributes'][attribute]['confidence']
        return confidence

    #
    # detects faces in the photo at the specified path, and returns info
    #
    def faceDetection(self, photopath):
        client = face_client.FaceClient(FACE_COM_APIKEY, FACE_COM_APISECRET)
        response = client.faces_recognize(DALELANE_FACETAG, file_name=photopath)
        faces = response['photos'][0]['tags']
        for face in faces:
            userid = ""
            faceuseridinfo = face['uids']
            if len(faceuseridinfo) > 0:
                userid = faceuseridinfo[0]['uid']
            if userid == DALELANE_FACETAG:
                smiling = self.getFaceDetectionAttributeValue(face, "smiling")
                smilingConfidence = self.getFaceDetectionAttributeConfidence(face, "smiling")
                mood = self.getFaceDetectionAttributeValue(face, "mood")
                moodConfidence = self.getFaceDetectionAttributeConfidence(face, "mood")
                self.storeResults(smiling, smilingConfidence, mood, moodConfidence)
            else:
                smiling = self.getFaceDetectionAttributeValue(face, "smiling")
                smilingConfidence = self.getFaceDetectionAttributeConfidence(face, "smiling")
                mood = self.getFaceDetectionAttributeValue(face, "mood")
                moodConfidence = self.getFaceDetectionAttributeConfidence(face, "mood")
                agemin = self.getFaceDetectionAttributeValue(face, "age_min")
                ageminConfidence = self.getFaceDetectionAttributeConfidence(face, "age_min")
                agemax = self.getFaceDetectionAttributeValue(face, "age_max")
                agemaxConfidence = self.getFaceDetectionAttributeConfidence(face, "age_max")
                ageest = self.getFaceDetectionAttributeValue(face, "age_est")
                ageestConfidence = self.getFaceDetectionAttributeConfidence(face, "age_est")
                gender = self.getFaceDetectionAttributeValue(face, "gender")
                genderConfidence = self.getFaceDetectionAttributeConfidence(face, "gender")
                # if the face wasnt recognisable, it might've been me after all, so ignore
                if "tid" in face and face['recognizable'] == True:
                    self.storeGuestResults(smiling, smilingConfidence, mood, moodConfidence, agemin, ageminConfidence, agemax, agemaxConfidence, ageest, ageestConfidence, gender, genderConfidence)
                    print face['tid']

    #
    # stores face results in the DB
    #
    def storeGuestResults(self, smiling, smilingConfidence, mood, moodConfidence, agemin, ageminConfidence, agemax, agemaxConfidence, ageest, ageestConfidence, gender, genderConfidence):
        cursor = self.connection.cursor()
        cursor.execute('INSERT INTO guestlog(isSmiling, smilingConfidence, mood, moodConfidence, agemin, ageminConfidence, agemax, agemaxConfidence, ageest, ageestConfidence, gender, genderConfidence) values(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)',
                        (smiling, smilingConfidence, mood, moodConfidence, agemin, ageminConfidence, agemax, agemaxConfidence, ageest, ageestConfidence, gender, genderConfidence))
        self.connection.commit()

    #
    # stores face results in the DB
    #
    def storeResults(self, smiling, smilingConfidence, mood, moodConfidence):
        cursor = self.connection.cursor()
        cursor.execute('INSERT INTO facelog(isSmiling, smilingConfidence, mood, moodConfidence) values(?, ?, ?, ?)',
                        (smiling, smilingConfidence, mood, moodConfidence))
        self.connection.commit()

monitor = AudienceMonitor()
monitor.initialiseDB()
monitor.prepareCamera()
while True:
    photopath = "data/photo" + monitor.getTimestampString() + ".bmp"
    monitor.captureFrame(photopath)
    try:
        faceresults = monitor.faceDetection(photopath)
    except:
        print "Unexpected error:", sys.exc_info()[0]
    os.remove(photopath)
    sleep(POLL_FREQUENCY_SECONDS)

我得到的错误是

^{pr2}$

我不明白这个错误！怎么了？Pygame找不到我的相机？在

Answer 1

list_cameras返回的是None，而不是一个列表，您看到的错误是当您试图检索None[0]时会发生什么。在

根据源代码，在非Linux平台上编译Pygame时，camera模块中的许多功能似乎都被悄悄地禁用了。即使这些函数应该在macos上运行，也有预处理器指令直接排除它。在

从Pygame 1.9.1：

/* list_cameras() - lists cameras available on the computer */
PyObject* list_cameras (PyObject* self, PyObject* arg)
{
#if defined(__unix__)
    PyObject* ret_list;
    PyObject* string;
    char** devices;
    int num_devices, i;

    num_devices = 0;
    ret_list = NULL;
    ret_list = PyList_New (0);
    if (!ret_list)
        return NULL;

    devices = v4l2_list_cameras(&num_devices);

    for(i = 0; i < num_devices; i++) {
        string = PyString_FromString(devices[i]);
        PyList_Append(ret_list, string);
        Py_DECREF(string);
        free(devices[i]);
    }
    free(devices);

    return ret_list;
#else
    Py_RETURN_NONE;
#endif
}

我认为这是对所发生的一切最有可能的解释。您的代码可能没问题，但您调用的函数只能返回None。我对Mac操作系统和camera模块的了解还不足以告诉你，如果你把所有这些语句都改成#if defined(__unix__) || defined(__APPLE__)并自己编译它，什么东西会工作或者不会工作。在