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Push the button above to watch and listen in real time, and to switch camera views. |
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Cam Select Up Cam Select Down Presented here is streaming video and audio from the camera. Press one of the buttons to change to the next higher or lower numbered camera. Press the "Reset to Normal View" button to return to non streaming mode. NOTE: Some cams may have the microphone switched off. |
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The camera system providing these images consists of a modified Philips commercial color security system, a headless
PC with capture card and a home made parallel port interface for switching. The Philips system, obtained from a jewelry store bankruptcy sale, consists of a color monitor and four color observation cameras with built-in microphones. The cameras require two pairs of ordinary CAT-3 telephone wire to connect to the monitor. Power for the cameras is provided through the twisted pairs by the monitor. Connectors at both ends of the CAT-3 are ordinary telephone RJ-11's. A quick and dirty schematic of the parallel port control is here. Because it gets a bit crowded in the DB25 shell if installing all eight transistors, only five were done, and only two are actually used in this implementation. This method of control involves turning on(bit high) of any one, or combinations of the eight parallel port pins D0 through D7. When the bit is set high, the pin, being at five volts, turns on the transistor switch and completes a connection to ground for the circuit connected to the collector of that transistor. The Philips camera monitor was modified such that a connection between the high side and common ground for the front panel control switches was brought out to the back panel for connection to the parallel port controller. The circuit board traces to the RJ-11 jack on the back of the monitor, originally used for connecting a slave monitor, were cut and the switch connections soldered there. This made for a convenient connection point for the home made parallel port control cable. In keeping things simple, the control for switching cameras involves presetting the monitor in the full screen mode. In this mode, hitting the "+" or "-" button on the monitor front panel increments or decrements the camera number that is to be displayed. The parallel port switcher merely operates the switch electronically by momentarily connecting the switch high side to ground by way of a user command to the server software. The server software for communicating with the parallel port is provided by BDLCAM available at http://bdlcam.com. This is a nice piece of work that has as its primary feature, the control of PTZ cameras. It is being used here for the parallel port control feature built into it. Video/audio stills and streaming software is webcamFLV by Nico Kooijman. I've tried many webcam programs and find webcamFLV to be the best performer of any of them by far. A cheap way to go for video capture cards(and what was done here) is to purchase a TV tuner card. Since TV analog tuners are soon to be dinosaurs, these cards can be had dirt cheap. All we want it for is the capture capability and the video input connector. |
