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JoaoPV
January 26, 2013, 11:42:40
Hello,

The documentation describes the meaning of the parameters in framReady (grabber, buffer & framenumber). I am just using the buffer, ans I would like to know when one should use the grabber parameter.

In my project, after initializing the camera, I assign its grabber an instance of my derived Listener class.

Stefan Geissler
January 28, 2013, 11:25:01
Hello,

You can use the grabber parameter, if you may change a property like exposure or gain or do something else with the grabber. stopLive() or changing video format is no good idea in the frameReady...

JoaoPV
January 28, 2013, 14:57:36
Hello Stefan,

Thank you for your follow up.

In my project I have three instances of the Listener derived class and assign each one to three Grabber objects (one for each camera in my project). Two of the cameras operate in Snap(true) mode, and are beeing constantly snapped. The third is using an external trigger.

With such a design, is there any chance for a frameReady event of one Listener object to "respond" to the new image from another Listener object (i.e., from another camera)?

Regards
Joao

Stefan Geissler
January 28, 2013, 15:28:10
Hi Joao,


With such a design, is there any chance for a frameReady event of one Listener object to "respond" to the new image from another Listener object (i.e., from another camera)?

If one of the Listener objects know about the others, yes. Or you send a message to your main program, which sets a flag into the other listeners, so they are informed about this.

JoaoPV
January 28, 2013, 15:53:31
Hello Stefan,

Thank you for your follow up and feedback.

In my project I have three instances of my Listener derived class, each assigned to one of three cameras. Is there any chance aframeReady event of one of the Listerners (from one of the cameras) be called when a new image is available from another camera?

Two of my cameras are operating in snap(true) mode, constantly being snapped. The third camera is operating in trigger mode.

I have been experiencing some odd behaviors, and would like to exclude this possibility.

Thanks,

Stefan Geissler
January 29, 2013, 10:36:56
Joao


I have been experiencing some odd behaviors, and would like to exclude this possibility.

This depends on what you mean by "odd" behavior". You should keep in mind, the grabbers create own threads and multithreading is a little bit complicated.

JoaoPV
January 31, 2013, 16:11:19
Stefan,

Thank you for all your clarifications. For now the "odd behaviors" were ideintified and contained on other parts of the project.

Regards,