How to process two cameras simultaneously?

[selvanathan]

Dear Sir,

How can i process two cameras simultaneously? I am using running image process.

I am sending you a sample program which contains single camera - running image process, like the same way how i can use two cameras simultaneously.

plz... help me..

thanks in advance

[selvanathan]

Hello Sir,
Is there anything wrong or not clear in my question?. Usually i got a replys with in a day. but this time i am not getting reply till now(6 days) . I need u r valuable reply urgently... plz help me...

[Sascha Schmidt]

Hallo selvanathan,

Sorry for late response.
Here is a modified version of your project, including simultaneously image processing with two cameras:

[selvanathan]

Dear Sir,
Thank you very much for your reply. Its very much useful for me. Thank u very much again....

[Stefan Geissler]

Hi Selvanathan,

I would like you to not provide any license keys in your samples. Thank you very much.
Thus I removed your attachments.

[selvanathan]

Hello Stefan,
No problem.... Sorry, here after i am not use license key in a sample programs. Thank u.

[selvanathan]

Dear Stefan,
I have another 2 doubts,

Doubt 1:

from the previous forums you know that i am using 2 cameras...,
from your sample program i am altering that code for my cameras like below

for Camera 1:
m_pGrabber_Cam1->openDev("DFx 31F03");
m_pGrabber_Cam1->setVideoFormat("UYVY (1024x768)");
m_pGrabber_Cam1->setFPS(15.00002);

for Camera 2;
m_pGrabber_Cam2->openDev("DFx 31AF03");
m_pGrabber_Cam2->setVideoFormat("UYVY (1024x768)");
m_pGrabber_Cam2->setFPS(15.00002);

But i got error ( see.. error message in attachment....)

in case i change the video format like

m_pGrabber_Cam1->setVideoFormat("UYVY (1024x768)");
m_pGrabber_Cam2->setVideoFormat("Y800 (1024x768)");

now the error not comes... how i keep camera 1 and camera 2's video format same...


Doubt 2:

like the same .... when using 2 cameras .....

inside frameready i need to process that...
camera one's image to gray scale.... and
camera two's image to edgedetuction.....

suppose i create two functions.....
DoImageProcessing_1( pBuffer); // this Apply gray scale to image
DoImageProcessing_2( pBuffer); // this Apply edge detuction to image

then how i identify which cameras buffer image is available currently in pBuffer and call above functions that i need..


void CListener_Cam1::frameReady( Grabber& param, smart_ptr<MemBuffer> pBuffer, DWORD FrameNumber)
{
pBuffer->lock();

if( camera 1) // what i do here
DoImageProcessing_1( pBuffer);
else
DoImageProcessing_2( pBuffer);

DrawBuffer(pBuffer);
pBuffer->unlock();
}

i need your valuable reply soon...
thanks in advance.....

[Stefan Geissler]

Hi Selvanathan,

Please refer to following link:

http://www.theimagingsource.com/en/resources/whitepapers/download/fwcamsbandwwp.en.pdf

This document contains a list of FireWire bandwidth allocation depending on video formats and frame rates.

UYVY needs 2 bytes per pixel, Y800 only one. Thus you should use a lower frame rate, e.g.7.5 fps in order to get both cameras running with UYVY video format.

Pointing to "Doubt 2:"

This is very simple. You have created your CListener object twice:


CListener_Cam1 mp_Listener1;
CListener_Cam1 mp_Listener2;

m_pGrabber_Cam1->addListener(&mp_Listener1);
m_pGrabber_Cam2->addListener(&mp_Listener2);

Your CListener_Cam1 class needs only a member, that receives the information which camera is in use, e.g. int "TheCamera". This must be set:


mp_Listener1.TheCamera = 1;
mp_Listener2.TheCamera = 2;

[selvanathan]

Dear Stefan,
Thank you... Thank You very much for u r reply.... Its very usful for me.. Doubt 2 is fully clear.. and i got what i need...

I under stood u r reply for doubt 1:

But I need to run both cameras in UYVY video format with 15 FPS

I am not able to change following points... all are very important for me....
1. Video Format - UYVY
2. Image Size - 1024 x 768
3. FPS - 15 (Min)
4. I should process continuous running images

To get all the above what i need to do.....or i need to change any system specifications

Plz... help me..... thanks in advance...

[selvanathan]

Dear Stefan,
Please help me to solve the above problem.... i tried in all the way but i am not able to connect both the cameras with above options.. so .. plz.. reply me .... as soon as possible.....

thanks in advanvce.......

[Stefan Geissler]

Hi,

Did you read the bandwidth PDF file? I gave the link to you. It says:
UYVY 1024x768 15 fps = 77% bandwidth allocation.

You may use two FireWire boards?

[selvanathan]

Dear Stefan,
Thank u very much for u r reply... i am very sorry .. i read u r pdf link.. but i under stood partially... now i under stood ... thank u very much again.

[Stefan Geissler]

Do you want to use two FireWire boards in your computer? This would fix your problem.

[selvanathan]

Ok Sir Thank u very much

[selvanathan]

Dear Stefan,
I alreay got a sample program from you for simeltaneously processing 2 cameras. Its working fine.. but i noticed that in windows task manager->Performance->CPU Usage is 100%.... why it takes 100% and how to decrease it.

and also i noticed that it happens when the buffer values transfered to array..

in frameready...

void CListener_Cam1::frameReady( Grabber& param, smart_ptr<MemBuffer> pBuffer, DWORD FrameNumber)
{
pBuffer->lock();
DrawBuffer(pBuffer);
pBuffer->unlock();
}

if i use above code CPU Usage takes only maximum of 33%.. but if i use like following ........

void CListener_Cam1::frameReady( Grabber& param, smart_ptr<MemBuffer> pBuffer, DWORD FrameNumber)
{
pBuffer->lock();
DoImageProcessing( pBuffer); // For Processing Image
DrawBuffer(pBuffer);
pBuffer->unlock();
}

void CListener_Cam1::DoImageProcessing( smart_ptr<MemBuffer> pBuffer)
{
smart_ptr<BITMAPINFOHEADER> pInf = pBuffer->getBitmapInfoHeader();
BYTE* pImageData = pBuffer->getPtr();
int iImageSize = pInf->biWidth * pInf->biHeight * pInf->biBitCount / 8 ;

//////// It Increases CPU Usage ///////////////////
for( int i = 0; i < iImageSize; i++)
{
pImageData[i] = 255 - pImageData[i];
}
//////// It Increases CPU Usage ///////////////////
}


it takes 100% CPU Usage........

Also I attached sample program for your reference.....

Plz Note:
I removed ImageSource Dlls & Lib to reduce file size and
I remove licence key as per u r advice in previous forums.

[Stefan Geissler]

Hi,

If you add some more imageprocessing, then the computer has more to do. That increases the CPU load. I will have a look later on your project.

[Stefan Geissler]

Hi,

On my old computer using only one DFK 21AU04 with no image processing, the CPU load is at 90%.