101 lines
2.6 KiB
Python
Executable File
101 lines
2.6 KiB
Python
Executable File
# Live video input from display class.
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import gl
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import GL
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# The live video input class.
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# Only instantiate this if have_video is true!
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class DisplayVideoIn:
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# Initialize an instance. Arguments:
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# vw, vh: size of the video window data to be captured.
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# position defaults to 0, 0 but can be set later
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def init(self, pktmax, vw, vh, type):
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self.pktmax = pktmax
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self.realwidth, self.realheight = vw, vh
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if type <> 'rgb':
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raise 'Incorrent video data type', type
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self.type = type
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self.width = vw
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self.height = vh
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#
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# Open dummy window
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#
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gl.foreground()
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gl.noport()
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self.wid = gl.winopen('DisplayVideoIn')
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self.x0 = 0
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self.x1 = self.x0 + self.width - 1
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self.y0 = 0
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self.y1 = self.y0 + self.height - 1
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# Compute # full lines per packet
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self.lpp = pktmax / self.linewidth()
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if self.lpp <= 0:
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raise 'No lines in packet', self.linewidth()
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self.pktsize = self.lpp*self.linewidth()
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self.data = None
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self.old_data = None
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self.dataoffset = 0
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self.lpos = 0
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self.hints = 0
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return self
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# Change the size of the video being displayed.
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def resizevideo(self, vw, vh):
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self.width = vw
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self.height = vh
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self.x1 = self.x0 + self.width - 1
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self.y1 = self.y0 + self.height - 1
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def positionvideo(self, x, y):
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self.x0 = x
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self.y0 = y
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self.x1 = self.x0 + self.width - 1
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self.y1 = self.y0 + self.height - 1
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# Remove an instance.
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# This turns off continuous capture.
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def close(self):
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gl.winclose(self.wid)
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# Get the length in bytes of a video line
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def linewidth(self):
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return self.width*4
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# Get the next video packet.
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# This returns (lpos, data) where:
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# - lpos is the line position
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# - data is a piece of data
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# The dimensions of data are:
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# - pixel depth = 1 byte
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# - scan line width = self.width (the vw argument to init())
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# - number of scan lines = self.lpp (PKTMAX / vw)
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def getnextpacket(self):
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if not self.data or self.dataoffset >= len(self.data):
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self.old_data = self.data
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self.data = gl.readdisplay(self.x0, self.y0, \
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self.x1, self.y1, self.hints)
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self.dataoffset = 0
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self.lpos = 0
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data = self.data[self.dataoffset:self.dataoffset+self.pktsize]
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while self.old_data and \
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self.dataoffset+self.pktsize < len(self.data):
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odata = self.old_data[self.dataoffset: \
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self.dataoffset+self.pktsize]
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if odata <> data:
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break
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print 'skip', self.lpos
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self.lpos = self.lpos + self.lpp
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self.dataoffset = self.dataoffset + self.pktsize
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data = self.data[self.dataoffset:\
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self.dataoffset+self.pktsize]
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lpos = self.lpos
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self.dataoffset = self.dataoffset + self.pktsize
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self.lpos = self.lpos + self.lpp
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return lpos, data
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