Hardware trigger + Auto exposure

[Pavel Kirienko]

Hi everyone,

I am keen on using two cameras with hardware synchronization and automatic exposure.

Here I see that this driver prevents using automatic exposure along with hardware triggering, but why? As far as I see it is not against the documentation.

Can we simply don't reset auto_exposure parameter if the hardware trigger is enabled?

Thanks in advance.

[Kevin Hallenbeck]

The options for triggering in this driver are:

stereo_TGR_AUTO = 0; stereo_TGR_SOFTWARE = 1; stereo_TGR_HARDWARE_RISING = 2; stereo_TGR_HARDWARE_FALLING = 3; stereo_TGR_L_MASTER_R_RISING = 4; stereo_TGR_L_MASTER_R_FALLING = 5; stereo_TGR_R_MASTER_L_RISING = 6; stereo_TGR_R_MASTER_L_FALLING = 7;

The auto_exposure parameter is only disabled for the master/slave modes. These modes use the flash output from the master to trigger the slave. The flash parameters are set using the is_IO() function and the IS_IO_CMD_FLASH_APPLY_GLOBAL_PARAMS value. From what I can tell, the slave camera triggers from a set time from the end of the master camera's previous exposure. With auto_exposure changing the exposure time every frame, syncing with this method is not possible. This can be shown in the IDS Imaging Windows demo program. There is something like a "Set Global Parameters" button, and the values change with exposure time.

Auto exposure can be used with stereo_TGR_SOFTWARE, stereo_TGR_HARDWARE_RISING, and stereo_TGR_HARDWARE_FALLING. In the SOFTWARE, the frame rate is set by software. In HARDWARE RISING/FALLING, this driver has no control over the frame rate. It would be controlled by another source.

This is my understanding. If you feel any of this is incorrect, please let me know.

Thanks, Kevin

[Pavel Kirienko]

(mistakenly posted an irrelevant message being half asleep, edited out)

I made it working, stay tuned for a pull request. It will be done within the next few days.

[Pavel Kirienko]

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