minifi-cam-display.py

import os,sys
import threading

from PyQt4 import QtGui
from PyQt4.QtCore import QObject, pyqtSignal, QTimer

content = None
content_lock = threading.Lock()
trigger = None
window = None
pic = None
pixmap = None

def update_img():
  global pixmap
  content_lock.acquire()
  if content is not None:
    if pixmap is None:
      pixmap = QtGui.QPixmap()
      pixmap.loadFromData(content, "PNG")
      pic.setPixmap(pixmap)
    pixmap.loadFromData(content, "PNG")
    window.setFixedWidth(pixmap.width());
    window.setFixedHeight(pixmap.height());
    pic.setFixedWidth(pixmap.width());
    pic.setFixedHeight(pixmap.height());
    pic.repaint()
  content_lock.release()

class GuiThread(threading.Thread):
  def run(self):
    global window
    global pic

    log.info('setting up ui')

    app = QtGui.QApplication([])
    window = QtGui.QMainWindow()
    window.setGeometry(0, 0, 640, 480)

    pic = QtGui.QLabel(window)
    pic.setGeometry(0, 0, 640, 480)
    #use full ABSOLUTE path to the image, not relative

    window.show()

    timer = QTimer()
    timer.timeout.connect(update_img)
    timer.start(15)

    app.exec_()

if threading.current_thread().name == 'MainThread':
  t = GuiThread()
  t.start()

log.info('waiting for flow files')

class ReadCallback(object):

  def process(self, input_stream):
    global content
    content_lock.acquire()
    content = input_stream.read()
    content_lock.release()
    log.info('read %d bytes' % len(content))
    return len(content)

def onTrigger(context, session):
  log.info('triggered')
  flow_file = session.get()

  if flow_file is not None:
    log.info('got flow file %s' % flow_file.getAttribute('filename'))
    session.read(flow_file, ReadCallback())
    session.transfer(flow_file, REL_SUCCESS)