class CameraWindow:
'''A simple class to set up a pygame window
A general design principle is that ALL openCV code should be encapsulated in
classes such as the above.`'''
writer = None
def __init__(self, fname=None):
'''Straightforward init
fname :
I think this needs to be *.avi
'''
# Set camera up first, as this is more likley to fail (I guess)
self.cv_cam = CVCam()
im = self.cv_cam.get_image()
arr = self.cv_cam.conv2array(im)
self.size = self.cv_cam.width, self.cv_cam.height
if fname:
self.writer = CVWriter(fname, self.size)
# Then, we set up our graphical environment
# SimpleVisionEgg is a custom set-up class I wrote to avoid boilerplate
# code duplication. It's a little clunky, sadly.
self.vision_egg = SimpleVisionEgg()
screen_center = [x/2.0 for x in self.vision_egg.screen.size]
tex_stim = TextureStimulus(mipmaps_enabled=False,
texture=Texture(arr),
size=self.size,
# We shouldn't invoke OpenGL texture
# filtering, as we take our texture size
# directly from the camera.
# the other option would be
# GL_NEAREST
texture_min_filter=GL.GL_LINEAR,
position=screen_center,
anchor='center')
# This gives us programmatic access to the actual video memory (if
# possible), so it should make things nice and fast. We still seem to be
# down around 14 fps, though, on the Mac. We're not going to get much
# faster on this front.
self.tex_object = tex_stim.parameters.texture.get_texture_object()
self.vision_egg.set_stimuli([tex_stim])
def update_image(self, t):
'''Grab an image from the camera and convert to a pygame.image
I'm using my SimpleVisionEgg system, so I need to discard the time
parameter `t` that gets passed in'''
im = self.cv_cam.get_image()
if self.writer:
self.writer.write_im(im)
arr = self.cv_cam.conv2array(im)
# Note - we use .put_sub_image because we aren't using dimensions that
# are a power of 2. There's a little more OpenGL magic going on somwhere
# that I don't know about...
self.tex_object.put_sub_image(arr)
events = pygame.event.get()
for event in events:
if event.type == pygame.QUIT:
# For some reason, using VisionEgg we don't exit cleanly and
# finalize our writer (thus, the movie is corrupted)
del self.writer
del self.cv_cam
self.vision_egg.quit()
def run(self):
'''Run forever (until we get a QUIT event)'''
self.vision_egg.set_functions(update=self.update_image)
self.vision_egg.go()
