# Class to grab frames from a window.
# (This has fewer user-settable parameters than Displayer.)
# It is the caller's responsibility to initialize the window and to
# ensure that it is current when using grabframe()
import gl, GL
import VFile
import GET
from VFile import Error
class VGrabber(VFile.VideoParams):
# XXX The constructor of VideoParams is just fine, for now
# Grab a frame.
# Return (data, chromdata) just like getnextframe().
def grabframe(self):
grabber = choose_grabber(self.format)
return grabber(self.width, self.height, self.packfactor)
# Choose one of the grabber functions below based upon a color system name
def choose_grabber(format):
try:
return eval('grab_' + format)
except:
raise Error, 'Unknown color system: ' + `format`
# Routines to grab data, per color system (only a few really supported).
# (These functions are used via eval with a constructed argument!)
def grab_rgb(w, h, pf):
if gl.getdisplaymode() <> GET.DMRGB:
raise Error, 'Sorry, can only grab rgb in single-buf rgbmode'
if pf <> (1, 1):
raise Error, 'Sorry, only grab rgb with packfactor (1,1)'
return gl.lrectread(0, 0, w-1, h-1), None
def grab_rgb8(w, h, pf):
if gl.getdisplaymode() <> GET.DMRGB:
raise Error, 'Sorry, can only grab rgb8 in single-buf rgbmode'
if pf <> (1, 1):
raise Error, 'Sorry, can only grab rgb8 with packfactor (1,1)'
if not VFile.is_entry_indigo():
raise Error, 'Sorry, can only grab rgb8 on entry level Indigo'
# XXX Dirty Dirty here.
# XXX Set buffer to cmap mode, grab image and set it back.
gl.cmode()
gl.gconfig()
gl.pixmode(GL.PM_SIZE, 8)
data = gl.lrectread(0, 0, w-1, h-1)
data = data[:w*h] # BUG FIX for python lrectread
gl.RGBmode()
gl.gconfig()
gl.pixmode(GL.PM_SIZE, 32)
return data, None
def grab_grey(w, h, pf):
raise Error, 'Sorry, grabbing grey not implemented'
def grab_yiq(w, h, pf):
raise Error, 'Sorry, grabbing yiq not implemented'
def grab_hls(w, h, pf):
raise Error, 'Sorry, grabbing hls not implemented'
def grab_hsv(w, h, pf):
raise Error, 'Sorry, grabbing hsv not implemented'
def grab_jpeg(w, h, pf):
data, dummy = grab_rgb(w, h, pf)
import jpeg
data = jpeg.compress(data, w, h, 4)
return data, None
def grab_jpeggrey(w, h, pf):
raise Error, 'sorry, grabbing jpeggrey not implemented'
|