"""VideoCapture.py
by Markus Gritsch <gritsch@iue.tuwien.ac.at>
"""
import vidcap
from PIL import Image, ImageFont, ImageDraw
import time, string
default_textpos = 'bl' # t=top, b=bottom; l=left, c=center, r=right
textcolor = 0xffffff
shadowcolor = 0x000000
def now():
"""Returns a string containing the current date and time.
This function is used internally by VideoCapture to generate the timestamp
with which a snapshot can optionally be marked.
"""
weekday = ('Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun')
#weekday = ('Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa', 'So')
#weekday = ('-', '-', '-', '-', '-', '-', '-')
y, m, d, hr, min, sec, wd, jd, dst = time.localtime(time.time())
return '%s:%s:%s %s %s.%s.%s' % (string.zfill(hr, 2), string.zfill(min, 2), string.zfill(sec, 2), weekday[wd], d, m, y)
class Device:
"""Create instances of this class which will then represent video devices.
For the lifetime of the instance, the device is blocked, so it can not be
used by other applications (which is quite normal Windows behavior).
If you want to access the device from another program, you have to delete
the instance first (e.g. del cam).
"""
def __init__(self, devnum=0, showVideoWindow=0):
"""devnum: VideoCapture enumerates the available video capture devices
on your system. If you have more than one device, specify
the desired one here. The device number starts from 0.
showVideoWindow: 0 ... do not display a video window (the default)
1 ... display a video window
Mainly used for debugging, since the video window
can not be closed or moved around.
"""
self.dev = vidcap.new_Dev(devnum, showVideoWindow)
self.normalfont = ImageFont.load_path('helvetica-10.pil')
self.boldfont = ImageFont.load_path('helvB08.pil')
self.font = None
def displayPropertyPage(self):
"""deprecated
Use the methods displayCaptureFilterProperties() and
displayCapturePinProperties() instead.
"""
print 'WARNING: displayPropertyPage() is deprecated.'
print ' Use displayCaptureFilterProperties() and displayCapturePinProperties()'
print ' instead!'
self.dev.displaypropertypage()
def displayCaptureFilterProperties(self):
"""Displays a dialog containing the property page of the capture filter.
For VfW drivers you may find the option to select the resolution most
likele here.
"""
self.dev.displaycapturefilterproperties()
def displayCapturePinProperties(self):
"""Displays a dialog containing the property page of the capture pin.
For WDM drivers you may find the option to select the resolution most
likele here.
"""
self.dev.displaycapturepinproperties()
def setResolution(self, width, height):
"""Sets the capture resolution. (without dialog)
(contributed by Don Kimber <kimber@fxpal.com>)
"""
self.dev.setresolution(width, height)
def getDisplayName(self):
""" Gets the Windows "friendly name" for the device (for example "Microsoft LifeCam VX-1000")
(contributed by Jeremy Mortis (mortis@tansay.ca)
"""
return self.dev.getdisplayname()
def getBuffer(self):
"""Returns a string containing the raw pixel data.
You probably don't want to use this function, but rather getImage() or
saveSnapshot().
"""
return self.dev.getbuffer()
def getImage(self, timestamp=0, boldfont=0, textpos=default_textpos):
"""Returns a PIL Image instance.
timestamp: 0 ... no timestamp (the default)
1 ... simple timestamp
2 ... timestamp with shadow
3 ... timestamp with outline
boldfont: 0 ... normal font (the default)
1 ... bold font
textpos: The position of the timestamp can be specified by a string
containing a combination of two characters. One character
must be either t or b, the other one either l, c or r.
t ... top
b ... bottom
l ... left
c ... center
r ... right
The default value is 'bl'
"""
if timestamp:
#text = now()
text = time.asctime(time.localtime(time.time()))
buffer, width, height = self.getBuffer()
if buffer:
im = Image.fromstring('RGB', (width, height), buffer, 'raw', 'BGR', 0, -1)
if timestamp:
if boldfont:
self.font = self.boldfont
else:
self.font = self.normalfont
tw, th = self.font.getsize(text)
tw -= 2
th -= 2
if 't' in textpos:
y = -1
elif 'b' in textpos:
y = height - th - 2
else:
raise ValueError, "textpos must contain exactly one out of 't', 'b'"
if 'l' in textpos:
x = 2
elif 'c' in textpos:
x = (width - tw) / 2
elif 'r' in textpos:
x = (width - tw) - 2
else:
raise ValueError, "textpos must contain exactly one out of 'l', 'c', 'r'"
draw = ImageDraw.Draw(im)
if timestamp == 2: # shadow
draw.text((x+1, y), text, font=self.font, fill=shadowcolor)
draw.text((x, y+1), text, font=self.font, fill=shadowcolor)
draw.text((x+1, y+1), text, font=self.font, fill=shadowcolor)
else:
if timestamp >= 3: # thin border
draw.text((x-1, y), text, font=self.font, fill=shadowcolor)
draw.text((x+1, y), text, font=self.font, fill=shadowcolor)
draw.text((x, y-1), text, font=self.font, fill=shadowcolor)
draw.text((x, y+1), text, font=self.font, fill=shadowcolor)
if timestamp == 4: # thick border
draw.text((x-1, y-1), text, font=self.font, fill=shadowcolor)
draw.text((x+1, y-1), text, font=self.font, fill=shadowcolor)
draw.text((x-1, y+1), text, font=self.font, fill=shadowcolor)
draw.text((x+1, y+1), text, font=self.font, fill=shadowcolor)
draw.text((x, y), text, font=self.font, fill=textcolor)
return im
def saveSnapshot(self, filename, timestamp=0, boldfont=0, textpos=default_textpos, **keywords):
"""Saves a snapshot to the harddisk.
The filetype depends on the filename extension. Everything that PIL
can handle can be specified (foo.jpg, foo.gif, foo.bmp, ...).
filename: String containing the name of the resulting file.
timestamp: see getImage()
boldfont: see getImage()
textpos: see getImage()
Additional keyword arguments can be give which are just passed to the
save() method of the Image class. For example you can specify the
compression level of a JPEG image by quality=75 (which is the default
value anyway).
"""
self.getImage(timestamp, boldfont, textpos).save(filename, **keywords)
if __name__ == '__main__':
import shutil
#shutil.copy('VideoCapture.py', 'C:\Python20\Lib')
#shutil.copy('VideoCapture.py', 'C:\Python21\Lib')
#shutil.copy('VideoCapture.py', 'C:\Python22\Lib')
#shutil.copy('VideoCapture.py', 'C:\Python23\Lib')
#shutil.copy('VideoCapture.py', 'C:\Python24\Lib')
#shutil.copy('VideoCapture.py', 'C:\Python25\Lib')
cam = Device(devnum=0)
#~ #cam.displayPropertyPage() ## deprecated
#~ #cam.displayCaptureFilterProperties()
#~ #cam.displayCapturePinProperties()
#~ #cam.setResolution(768, 576) ## PAL
#~ #cam.setResolution(352, 288) ## CIF
#~ cam.saveSnapshot('test.jpg', quality=75, timestamp=3, boldfont=1)
print "Friendly name: ", cam.getDisplayName()
