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Video playback

media_player_mpy plugin

The media_player_mpy plugin is based on MoviePy. As of OpenSesame 3.1, it is included by default with the Windows and Mac OS packages of OpenSesame. If it is not installed, you can get it by installing the opensesame-plugin-media_player_mpy package, as described here:

The source code is hosted at:

media_player_vlc plugin

The media_player_vlc plugin is outdated. It's better to use the media_player_mpy plugin instead.

The media_player_vlc plugin is based on the well-known VLC media player. As of OpenSesame 3.1, it is no longer included by default with the Windows and Mac OS packages of OpenSesame. If it is not installed, you can get it by installing the opensesame-plugin-media_player_vlc package, as described here:

The source code is hosted at:

In addition, you need to install the VLC media player in the default location:

Troubleshooting: If you encounter a black screen when running your experiment in fullscreen (i.e. the video appears to play, but you don't see anything), please try using a different backend (i.e. switch from legacy to xpyriment or vice versa), or change the backend settings for the legacy backend.

OpenCV

OpenCV is a powerful computer vision library, which contains (among many other things) routines for reading video files.

The following example shows how to play back a video file, while drawing a red square on top of the video. This example assumes that you're using the legacy backend.

import cv2
import numpy
import pygame
# Full path to the video file in file pool
path = pool['myvideo.avi']
# Open the video
video = cv2.VideoCapture(path)
# A loop to play the video file. This can also be a while loop until a key
# is pressed. etc.
for i in range(100):
    # Get a frame
    retval, frame = video.read()
    # Rotate it, because for some reason it otherwise appears flipped.
    frame = numpy.rot90(frame)
    # The video uses BGR colors and PyGame needs RGB
    frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
    # Create a PyGame surface
    surf = pygame.surfarray.make_surface(frame)
    # Now you can draw whatever you want onto the PyGame surface!
    pygame.draw.rect(surf, (255,0,0), (100, 100, 200, 200))
    # Show the PyGame surface!
    exp.surface.blit(surf, (0, 0))
    pygame.display.flip()