How to enable external trigger? about tiscamera

[TIS-Edgar]

Hi,

Trigger should work with every camera.
What you have to do is enable the trigger mode.
Simply set the privacy flag. This will give you an frozen image, indicating that trigger is enabled.

After that the external trigger should work as expected.

[TIS-Edgar]

Is this issue fixed, or do you need further assistance?

[yishinli]

Thanks, I need help.

I tried the following commands, and found something regarding trigger. But, that is it; I don't know how to take pictures with external trigger.

sudo uvcdynctrl -i tisEUVC.xml -d /dev/videoTIS1
v4l2-ctl --device=/dev/videoTIS1 --list-ctrls
gain (int) : min=16 max=63 step=1 default=16 value=16
extio (bool) : default=0 value=0
trigger (bool) : default=0 value=0
x_offset (int) : min=0 max=8 step=2 default=0 value=0
y_offset (int) : min=0 max=0 step=2 default=0 value=0
exposure_absolute (int) : min=1 max=2500 step=1 default=127 value=300
privacy (bool) : default=0 value=0

Please clarify which tool/command should I use to capture pictures with external trigger.

Thank you very much.

[TIS-Edgar]

OK, to see if external trigger is working you can use guvcview.

1. Set the privacy flag
   You will now see a fixed image.
2. Activate your external trigger
   The image should now be updated.

If this is the case, triggering works.

For your options concerning trigger mode activation:
You can either activate it with v4l2-ctl:
v4l2-ctl --device=/dev/video0 --set-ctrl=privacy=1
or you use ioctl if you wish to set it programmatically.

I would have to set up a little example on how to do that, if you wish to use ioctl.

[yishinli]

Thanks, after setting the "Privacy" flag, I can see the "fixed image". After activating the "external trigger", the image get updated continuously.

Questions:

1. If I would like to only take ONE picture, what I should do is generating a short (>10us) pulse instead of keep activating the external trigger, correct?
2. From the DMK22BUC03 manual, it prints the "Shutter 1/10,000S to 1/4S".
   If I would like to set the shutter as "1/10,000S", should I set "exposure_absolute" to 1?
3. What's the function for "trigger" of v4l2-ctrl property?

[TIS-Edgar]

1. Each pulse should cause an image capture.

2. To quote the v4l2 API documentation:
   V4L2_CID_EXPOSURE_ABSOLUTE Determines the exposure time of the camera sensor. The exposure time is limited by the frame interval. Drivers should interpret the values as 100 µs units, where the value 1 stands for 1/10000th of a second, 10000 for 1 second and 100000 for 10 seconds.
   Setting it to 1 will give the wished effect.

3. I assume you are referring to software trigger?
   Do you have the latest firmware version (163) ?
   If you do you should find a field software_trigger after applying the uvc extension unit.
   Here an overview over all controls with firmware v163 and uvc extensions enabled.

   brightness (int) : min=0 max=255 step=1 default=128 value=128
   gain (int) : min=16 max=63 step=1 default=16 value=16
   extio (bool) : default=0 value=0
   trigger (bool) : default=0 value=0
   software_trigger (button) :
   x_offset (int) : min=0 max=320 step=2 default=0 value=0
   y_offset (int) : min=0 max=240 step=2 default=0 value=0
   exposure_absolute (int) : min=1 max=2500 step=1 default=127 value=300
   privacy (bool) : default=0 value=0

Both trigger mode and software trigger can be set through ioctl and v4l2-ctl.
Trigger Mode:
v4l2-ctl --device=/dev/video0 --set-ctrl=trigger=true
Software Trigger:
v4l2-ctl --device=/dev/video0 --set-ctrl=software_trigger=

[yishinli]

Hi Edgar,

Thanks for your help. The external trigger works. My camera model is DMK22BUC03.
Here are my steps:

1. Upgrade firmware version to 163
2. Execute the following commands:

sudo uvcdynctrl -i tiscamera/data/uvc-extensions/tisEUVC.xml -d /dev/videoTIS1
v4l2-ctl --device=/dev/videoTIS1 --set-ctrl=trigger=1

-Yishin