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Live Video Feed over one RS232 line (Rx or Tx)

Started by GregNash July 3, 2009
Hi all,
I have an idea to try and transmit live video camera data over one RS232
(either Tx or Rx) line. The problem is that I don’t know how to go about
processing the camera data. If the camera data was transmitted over an i2c
bus, then this would be possible (as per
http://www.gedanken.demon.co.uk/rs232-converters/i2c.html) but I’m not
sure whether cameras transmit pixel data over i2c.

For everyone’s information, the maximum Baud rate for the RS232 lines I
intend to use is 921,600Bd – I think that’s a lot.

Furthermore, I would like the camera to be high resolution and in colour.
Y’know, I don’t want much. :-)

Thanks very much for taking the time to read this,

Greg


"GregNash" <g-nash@hotmail.com> schreef in bericht
news:zdKdnSMDbso7itPXnZ2dnUVZ_jKdnZ2d@giganews.com...
> Hi all, > I have an idea to try and transmit live video camera data over one RS232 > (either Tx or Rx) line. The problem is that I don&#2013265922;?Tt know how to go about > processing the camera data. If the camera data was transmitted over an i2c > bus, then this would be possible (as per > http://www.gedanken.demon.co.uk/rs232-converters/i2c.html) but I&#2013265922;?Tm not > sure whether cameras transmit pixel data over i2c.
That of course depends entirely on the type of camera you're using. There have been cheap Mattell 640x480 camera's which did use RS232 to tranmit the JPEG converted image to a PC. But generaly, if the camera has I2C, this is only used to set parameters and not to transfer the pixel data.
> For everyone&#2013265922;?Ts information, the maximum Baud rate for the RS232 lines I > intend to use is 921,600Bd &#2013265922;?" I think that&#2013265922;?Ts a lot.
Well that depends on the sensor size and how patient you are :) With a modern 12Mpixel sensor you'll be waiting a while for each transfer.
> Furthermore, I would like the camera to be high resolution and in colour. > Y&#2013265922;?Tknow, I don&#2013265922;?Tt want much. :-) > > Thanks very much for taking the time to read this, > > Greg
Antoon
On Jul 3, 10:37 am, "GregNash" <g-n...@hotmail.com> wrote:

> I have an idea to try and transmit live video camera data over one RS232 > (either Tx or Rx) line. The problem is that I don=92t know how to go abou=
t
> processing the camera data.
Assuming you want to use the RS232 line as intended (and not try to evaluate its suitability for some other signaling scheme) the key to your problem is going to be real time compression. Your approach should consist of the following: 1) See if you can buy a solution if not 2) Lab experiment: get two PCs, one with a webcam or other video source, connect them with a serial line and running streaming software such as VLC. Find some compression settings that give you the best plausible performance for your data rate. 3) Build or buy appropriate embedded hardware to re-implement the solution of step #2 in a small / cheaper / more power efficient platform consistent with your (unstated) requirements