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I'm in the computer sciences engineering field. For a project, I need to use a camera, take a photo, process it and take a decision and so on. It's a hard real time problem as we have timing constraints. Hence, I would like to compute the time required to take a single photo and have it at disposition (by looking at a camera specification).

I'm a bit confused about how I could process and what values are important :

  • On this paper, there is a formula to compute the frame time. I don't understand what integration time is, the exposure time ?
  • Here, it's written that FPS is the performance of the camera body. Could I compute the frame time by 1/FPS + Exposure time ? Are there other things to take in account ?

Thanks in advance !

Ripitchip
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  • What is your use case? Are you attempting to analyze a real-time video stream? Or are you interested in obtaining photos that are precisely timed, such as every 0.25 seconds? –  Oct 01 '21 at 18:20
  • The datasheet for your camera should tell you how to calculate the delay required to get a frame from the camera. If it doesn't, then you might have to measure it. – user1850479 Oct 02 '21 at 00:22
  • @maples : neither of them. I'm interested to take one photo at a time, and to compute the time required for one photo to know if it's quick enough for my application. – Ripitchip Oct 02 '21 at 18:56
  • @user1850479 : The datasheet of most multi/hyperspectral cameras speaks about fps but not really about acquisition time (here, an example with MAIA M2). – Ripitchip Oct 02 '21 at 18:56
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    That's a marketing flier not a datasheet. Contact the vendor and ask for the actual datasheet. – user1850479 Oct 02 '21 at 22:35

1 Answers1

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This is essentially a machine vision application. There are industrial cameras made for machine vision applications where reliable throughputs are critical.

That’s the place to start — specifying the requirements. It is likely that the output does not require the resolution and optical quality of a consumer stills camera. It is also likely that vendor software support for reliable throughput will make life easier.

On the other hand, off the shelf cinema oriented cameras can provide 2K, 4K, 6K, or even 8K RAW feeds at 30, 60, 120, or more frames per second. Depending on your budget (including processing and storage capabilities).

For an ordinary stills camera, I think you would want to test specific cameras. Historically, their performance is variable due to internal mechanical physics, buffer size limits, processing power, and interface bandwidth.

It’s worth calculating the duty cycle. Ten frames per second is 36,000 frames per hour. For a conventional stills camera with a mechanical shutter, that’s less than thirty hours for one million activations. That’s exceeds the expected life of most stills cameras.

ben rudgers
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  • @Bob Macaroni McStevens : I'm mostly interested in multi/hyperspectral camera which are industrial cameras, but whose datasheet sometimes specify the number of capture per second like the MicaSense but others not. So basically, you are telling me that the performance depends and I should just test it out ? – Ripitchip Oct 02 '21 at 18:59
  • @Ripitchip I am saying start with a specification. – ben rudgers Oct 02 '21 at 23:55