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Shaun07

Camera Attributes & Auto Exposure

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Hello,

Research purpose, I am using Imagining Source (DMK 33Ux249) camera to capture the laser beam. I am trying to write a code for auto exposure according to power level of laser beam. I used Vision acquistion for capturing live video image and tried to open the front panel of the vision acquistion. 

But, I couldn't figure out how to set the exposure level automatically.  Basically whole task is,

1. Capturing live image

2. set the exposure time according to laser beam profile

3. Remember the exposure the time and set again according to next frame or beam profile.

Is anybody previously work or have an idea to solve this issue please let me know. 

 

Thanks 

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If the camera is Genicam, i.e. driven by IMAQdx, check if it has a settable attribute for auto exposure. Auto exposure normally means a canned algorithm inside the camera which shoots images at increasing exposure times, till the average intensity is middle of the way, and then keeps that for good. If it hasent, just program it in your code.

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I have to program it. I don't have any idea how to do that's why I posted over here. 

Do you have any idea how can I program it?

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Shoot one image at a given exposure time. Get a meaningful measure of its intensity (e.g. the maximal pixel value, the average of the pixel values in a region around the maximum or in a ROI). If too large halve exposure, if too small double exposure. Repeat in a loop till this measure is in the middle of the acceptable range.

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