Wireless Video

[squidge]

@fatjuicymole
Well right now I am reading the video data directly from a webcam that is plugged in to one of my usb ports on my laptop. I need to modify the code to receive video data from a vehicle flying in the air with a camera attached to it.

And? How does the flying camera transmit its data? Wifi? Bluetooth?

[khrave]

It transmits it via wifi to a computer on the ground purposed to view video data and other stats about the flying vehicle.

[squidge]

So what you need to do is create a server. What type of connection does it expect?

[khrave]

We're using a camera that is mounted on the flying vehicle, which is attached via usb to a gumstix overo fire board (also mounted on the flying vehicle) which will transmit various types of information, including video data, through a tcp/ip wireless-g signal to the computer on the ground. I need to be able to get the video data from the vehicle and display it. I feel like it is an easy modification to the code I posted earlier, but I need a push in the right direction. Thanks!

[squidge]

Wireless-G is a transport medium (well, Link Layer) for transferring data over the air-ways
TCP over IP is a transport medium
Before we can go further we need to know what Application Layer the camera uses. For example, HTTP, FTP, Proprietary, etc.

[khrave]

Oh, my apologies, my terminology knowledge is relatively low. We're using UDP, sending raw data through packets between the ground computer and the vehicle.

[squidge]

In which case, there is a nice example for UDP in the QUdpSocket documentation in Assistant.

[Qt Coder]

The same way I need to use IP camera in my proje.My question is

1) How to know which application layer the camera uses?

[squidge]

a) Wireshark (examine communication), or
b) Experimentation, or
c) Documentation

[Qt Coder]

I installd Qt 4.6.2 and OpenCV2.0 on my windows machine

Qt is installed at C:\Qt\2010.02.1\Qt and openCV is installed at c:\OpenCV2.0

I downloaded the QtOpenCV example which
Opens a webcam, and displays the image in the widget.
from http://opendesktop.org/content/show....SSID=kfmhtqozm


I copied opencv folder where it contains cv.h,higui.h in Qt include folder also I changed .pro file as

INCLUDEPATH += "C:\OpenCV2.0\src\cv"
INCLUDEPATH += "C:\OpenCV2.0\src\cxcore"
INCLUDEPATH += "C:\OpenCV2.0\src\cvaux"
INCLUDEPATH += "C:\OpenCV2.0\src\highgui"
 
LIBS += -L "C:\OpenCV2.0\lib"
LIBS +=  -lcv -lhighgui

INCLUDEPATH += "C:\OpenCV2.0\src\cv"
INCLUDEPATH += "C:\OpenCV2.0\src\cxcore"
INCLUDEPATH += "C:\OpenCV2.0\src\cvaux"
INCLUDEPATH += "C:\OpenCV2.0\src\highgui"

LIBS += -L "C:\OpenCV2.0\lib"
LIBS +=  -lcv -lhighgui

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when I compile example it gives me error

c:/qt/2010.02.1/mingw/bin/../lib/gcc/mingw32/4.4.0/../../../../mingw32/bin/ld.exe: cannot find -lcv
collect2: ld returned 1 exit status

c:/qt/2010.02.1/mingw/bin/../lib/gcc/mingw32/4.4.0/../../../../mingw32/bin/ld.exe: cannot find -lcv
collect2: ld returned 1 exit status

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why this error occures?

[squidge]

Where is cv?

[Qt Coder]

OpenCV is installed at C:\OpenCV2.0

Qt 4.6.2 is installed at C:\Qt\2010.02.1\qt

also I have copied C:\OpenCV2.0\include\opencv folder to Qt include folder

still it gives this error

1.
      c:/qt/2010.02.1/mingw/bin/../lib/gcc/mingw32/4.4.0/../../../../mingw32/bin/ld.exe: cannot find -lcv
   2.
      collect2: ld returned 1 exit status

1.
      c:/qt/2010.02.1/mingw/bin/../lib/gcc/mingw32/4.4.0/../../../../mingw32/bin/ld.exe: cannot find -lcv
   2.
      collect2: ld returned 1 exit status

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