Multicam V2.1 : 4 cams : bad / faulty images using opencv/python on RPI 4

Raspberry Pi Cameras sync-stereo-camera-hat
1

Hello,

I am developping a system that need 4 images taken almost simultaneously. So, I bought your multicam adapter v2.1.

I have developped the following program using python+opencv, based on your code example (4cam_cv3.py)

  • openthecamera device (cam = cv2.VideoCapture(0) )
  • configure the 4 cams (gpio+i2c+ resolution/exposure config)
  • do 300 times
    • do 4 times
      • select the cam (gpio...)
      • read cam image (in order to empty the opencv cam buffer , )
      • read cam image (in order to empty the opencv cam buffer)
      • read cam image (in order to empty the opencv cam buffer)
      • read cam image ( ret, frame = cam.read() )
      • write cam image on file
Unfortunately I am getting a lot of faulty images : in some image I am getting a set of multicolored lines + half & top bottom of these images are swapped).

Since the camera are not synchronized I guess that swapping the mipi signal in the middle of an image transfer generate this kind of problem (i.e. synchronization issue).

Slowing down everything seems to reduce the number of faulties image but it is then too slow for our application.

The Multi_Camera_Adapter_V2.1/4cam_cv3.py display correctly the 4 images in fast sequence, I see no faulty image but I think that faulty images happend but are quicly hidden by new images coming.

Can you please help me (we are working on a real industrial project so if it works correctly we will need a lot of your boards)

For sure I can provide you my detailled code.

Best regards,

Thierry

2

Hi,

Thanks for your business.

At present, our hardware does not support synchronize capture due to the clock is out of sync.

So you can’t get each camera’s image. Because we can’t ensure after the first camera capture done, we are not sure the second camera is beginning capture.

 

3

Hi,

Thanks for your business.

At present, our hardware does not support synchronize capture due to the clock is out of sync.

So you can’t get each camera’s image. Because we can’t ensure after the first camera capture done, we are not sure the second camera is beginning capture.

 

4

Hi,

Thanks for your business.

At present, our hardware does not support synchronize capture due to the clock is out of sync.

So you can’t get each camera’s image. Because we can’t ensure after the first camera capture done, we are not sure the second camera is beginning capture.

 

5

Hi,

Thanks for your business.

At present, our hardware does not support synchronize capture due to the clock is out of sync.

So you can’t get each camera’s image. Because we can’t ensure after the first camera capture done, we are not sure the second camera is beginning capture.

 

6

Thank you for your fast answer.

Do you mean it is not possible to get correct picture sequentially of each camera ?

(i.e. cam1, cam2, cam3, cam4, cam1,cam2,cam3, cam4 etc )

7

I mean even wasting reading some images in order to let the synchro occur ?

i.e cam1 cam1 cam1, cam2, cam2, cam2, cam3 etc

8

Hi,

What I mean is that due to the clock is our of sync, it does not support

trigger capture synchronize.

you can get each camera’s image one by one instead of sync.