execute_async() not working as expected

[pirobot]

My set up is Ubuntu 12.04, ROS Groovy and the Debian Ecto packages.

I expected the following code to run the Canny edge detection for 5 seconds and then quit. However, the video window never appears and the program simply exists after 5 seconds. If I use sched.execute() instead of sched.execute_async(), the video and edge processing displays properly but of course never exits.

!/usr/bin/env python

import sys
import time
import ecto
from ecto_opencv.highgui import VideoCapture, imshow, FPSDrawer
from ecto_opencv.imgproc import Canny

video_cap = VideoCapture(video_device=0, width=320, height=240)
fps = FPSDrawer()
edges = Canny(threshold1=100.0, threshold2 = 50.0)

plasm = ecto.Plasm()
plasm.connect(video_cap['image'] >> fps['image'],
fps['image'] >> edges[:],
edges[:] >> imshow(name='video_cap')['image'],
)

sched = ecto.Scheduler(plasm)
sched.execute()

time.sleep(5)

sched.stop()

[vrabaud]

I tried with cells that write stuff and it's the same behavior. @ethanrublee , any idea ?