Question

我正在尝试在我的心理任务期间捕获定时屏幕截图。我有一个固定十字架，然后是屏幕左侧和右侧的两个面，然后是一个点。我只想要两个面部出现在屏幕上的1秒时间段的屏幕截图。例程中有10个不同的面对，并且例程循环3次。理想情况下，我希望通过此代码将30张图像保存到我的计算机中。我的代码到目前为止：

from __future__ import division  # so that 1/3=0.333 instead of 1/3=0
from psychopy import visual, core, data, event, logging, sound, gui
from psychopy.constants import *  # things like STARTED, FINISHED
import numpy as np  # whole numpy lib is available, prepend 'np.'
from numpy import sin, cos, tan, log, log10, pi, average, sqrt, std, deg2rad, rad2deg,    linspace, asarray)
from numpy.random import random, randint, normal, shuffle
import os  # handy system and path functions

import socket
import time

# Store info about the experiment session
expName = 'DotProbe_EyeTracker_BSchool' 
expInfo = {u'session': u'001', u'participant': u''}
dlg = gui.DlgFromDict(dictionary=expInfo, title=expName)
if dlg.OK == False: core.quit()  # user pressed cancel
expInfo['date'] = data.getDateStr()  # add a simple timestamp
expInfo['expName'] = expName

# Setup files for saving
if not os.path.isdir('data'):
    os.makedirs('data')  # if this fails (e.g. permissions) we will get error
filename = 'data' + os.path.sep + '%s_%s' %(expInfo['participant'], expInfo['date'])
logFile = logging.LogFile(filename+'.log', level=logging.EXP)
logging.console.setLevel(logging.WARNING)  # this outputs to the screen, not a file

# An ExperimentHandler isn't essential but helps with data saving
thisExp = data.ExperimentHandler(name=expName, version='',
    extraInfo=expInfo, runtimeInfo=None,
    originPath=None,
    savePickle=True, saveWideText=True,
    dataFileName=filename)

# Start Code - component code to be run before the window creation

# Setup the Window
win = visual.Window(size=(1366, 768), fullscr=True, screen=0, allowGUI=False,      
    allowStencil=False, monitor='testMonitor', color=[-1,-1,-1], colorSpace='rgb')
myClock = core.Clock()

# store frame rate of monitor if we can measure it successfully
expInfo['frameRate']=win.getActualFrameRate()
if expInfo['frameRate']!=None:
    frameDur = 1.0/round(expInfo['frameRate'])
else:
    frameDur = 1.0/60.0 # couldn't get a reliable measure so guess

# Initialize components for Routine "instructions"
instructionsClock = core.Clock()
text = visual.TextStim(win=win, ori=0, name='text',
text='Respond to the probe once it appears. EIther click "2" when probe replaces left     face or click "3" when probe replaces right face.',    font='Arial',
    pos=[0, 0], height=0.1, wrapWidth=None,
    color='white', colorSpace='rgb', opacity=1,
    depth=0.0)

# Initialize components for Routine "block1"
block1Clock = core.Clock()
fixation = visual.TextStim(win=win, ori=0, name='fixation',
    text='+',    font='Arial',
    pos=[0, 0], height=0.1, wrapWidth=None,
    color='white', colorSpace='rgb', opacity=1,
    depth=0.0)

leftimage = visual.ImageStim(win=win, name='leftimage',
    image='sin', mask=None,
    ori=0, pos=[0,0], size=[1, 1.34],
    color=[1,1,1], colorSpace='rgb', opacity=1,
    texRes=128, interpolate=False, depth=-1.0)

rightimage = visual.ImageStim(win=win, name='rightimage',
    image='sin', mask=None,
    ori=0, pos=[0,0], size=[1, 1.34],
    color=[1,1,1], colorSpace='rgb', opacity=1,
    texRes=128, interpolate=False, depth=-2.0)

probe = visual.ImageStim(win=win, name='probe',
    image='sin', mask=None,
    ori=0, pos=[0,0], size=[0.5, 0.5],
    color=[1,1,1], colorSpace='rgb', opacity=1,
    texRes=128, interpolate=False, depth=-3.0)

#Get and save a screen shot" of everything in stimlist:
stimlist = [leftimage, rightimage]
t0 = myClock.getTime()
rect=(-1,1,1,-1)
screenshot = visual.BufferImageStim(win, stim=stimlist, rect=rect)
    # rect is the screen rectangle to grab, (-1,1,1,-1) is whole screen
    # as a list of the edges: Left Top Right Bottom, in norm units.

# Create some handy timers
globalClock = core.Clock()  # to track the time since experiment started
routineTimer = core.CountdownTimer()  # to track time remaining of each (non-slip) routine

Answer 1

正如其他人所建议的那样，使用win.getMovieFrame和win.saveMovieFrames。您不需要visual.BufferImageStim。当你完成脚本时，你可能最终会遇到循环过度。我会拍摄截图，因为实际的实验正在运行，而不是事先“模拟”。它确保您的屏幕截图准确描述了实验过程中实际发生的事情 - 如果您犯了错误并且错误地绘制了东西:-)当然，如果截图的目的纯粹是为了文档，请删除/在运行实际实验以提高性能时，将这些行排除在外。

# Loop through trials. You may organize them using ``data.TrialHandler`` or generate them yourself.
for trial in myTrialList:
    # Draw whatever you need, probably dependent on the condition. E.g.:
    if trial['condition'] == 'right':
        rightimage.draw()
    else:
        leftimage.draw() 
    fixation.draw()

    # Show your stimulus
    win.flip()

    # Save screenshot. Maybe outcomment these line during production.
    win.getMovieFrame()   # Defaults to front buffer, I.e. what's on screen now.
    win.saveMovieFrames('screenshot' + trial['condition'])  # save with a descriptive and unique filename.                                .

Answer 2

我无法对此进行测试，因为我没有在当前的计算机上设置PyschoPy，但使用Window.getMovieFrame()和Window.saveMovieFrames()会让您到达您需要的位置，例如：

screenshot = visual.BufferImageStim(win, stim=stimlist, rect=rect)
    # rect is the screen rectangle to grab, (-1,1,1,-1) is whole screen
    # as a list of the edges: Left Top Right Bottom, in norm units.
# screenshot is currently on the 'back' buffer as we haven't flipped yet
win.getMovieFrame(buffer='back')
win.saveMovieFrames('stimuli.png')

在PsychoPy实验期间截图

2 个答案: