Quad Bayer format images

Raspberry Pi Cameras
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  1. Where did you get the camera module(s)?
    Arducam website
  2. Model number of the product(s)?
    64MP Hawkeye
  3. What hardware/platform were you working on?
    Raspberry Pi
  4. Instructions you have followed. (link/manual/etc.)
    Arducam install instructions and libcam instructions
  5. Problems you were having?

Could you please confirm the format of the Sensor’s bayer filter?

I was under the impression that this camera has a quad bayer format, where each block of 16 pixels has 8 green, 4 blue and 4 red pixels arranged in blocks of 4. Is that true, or is the sensor a more traditional bayer format (i.e repeating blocks of RGGB)?

I am interested in getting the full 10bit Quad-bayer image from the camera if possible. I have used the command below which outputs a DNG of the bayer pattern, but this does not seem to be in the quad bayer format - it seems to be in RGGB format. If the sensor is quad-bayer, is there any way to retrieve the unprocessed quad bayer pixels from the camera?

libcamera-still --width 9152 --height 6944 -r -o test.jpg

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@bigollie93

I was under the impression that this camera has a quad-bayer format, where each block of 16 pixels has 8 green, 4 blue, and 4 red pixels arranged in blocks of 4. Is that true, or is the sensor a more traditional bayer format (i.e repeating blocks of RGGB)?

Indeed.

DNG is RAW image + shooting parameters, like exposure gain, and white balance related.

If you want to get the rawest, you can try libcamera-raw.
Or turn off media-controller and use v4l2 to fetch,

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Hi Edward,

Thanks for the information. Apologies but your message is slightly ambiguous.

Just to be sure, can you confirm that the Bayer format here is not Quad Bayer, and is actually RGGB?

Thanks

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@bigollie93

Don’t worry.

I made sure it was RGGB.

Quad Bayer is RYYB,we do not yet have products that use to.

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Thank you for the information Edward!

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Just to say, you might want to edit the information on this page, because it states that the sensor has quad bayer format:

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@bigollie93

Do you mean this?

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31506×691 196 KB

I did not find more introductions

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I have the same concerns/confusion as @bigollie93 regarding the sensor and I don’t think this has been understood or rectified

So the confusion is this:

The arducam website claims it has a Quad Bayer Coding (QBC) Colour Filter Array different from the regular Bayer filter - BGGR

However, when capturing a Dng RAW Bayer data straight from the camera sensors, the Libcamera app reports that the file is saved in an RGGB format (which doesn’t agree with the QBC Filter)

The QBC here has nothing to do with the number of camera as suggested by the answers by @Edward

So please confirm the CAMERA FILTER Array used on the pi hawk-eye sensor and how that can be saved if it’s truly a QBC

Thanks

images (2)
images (2)769×399 43.6 KB

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@Elvis

The array of the camera is a Quad-bayer Filter but it goes through remosaic, so the output is a Bayer Filter. This is because isp processing requires the format of Bayer Filter and does not support Quad-bayer Filter.

image

1 Like
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Thanks @Edward for the prompt reply, this makes it clearer and fuels my next question:

How can I access the quad Bayer data before the remosaic process? I need the sensor data in its original spatial form.

Thanks once again for your prompt reply

-Elvis

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@Elvis

This requires modifying the camera driver, which is very large, and requires the cooperation of the module manual.

We are not currently developing sensor manuals, so you may not be able to do this work.

If you really need it, you need to contact the salesperson for customization.

1 Like
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@Edward

I see

However, I’d like to re-rearrange the bayer bggr array back to the initial array - I’m assuming this will be easier in my use case

Is it possible to share the “formula” with which it was rearranged to bggr so I can undo it in software

That’ll be most helpful

The “formula” doesn’t have to be a code as I understand that may be difficult, a pictorial representation like the picture below will do

Thanks once again

Elvis

images (3)
images (3)699×222 49.6 KB

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@Elvis

There are relevant confidentiality clauses, which are not public. Forgive me for not having the right to share this with you.

If you have this information, you can contact [email protected]

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@Edward

I didn’t quite get what you mean in regards the contact email, are you asking that I contact the email for additional information regarding this?

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@Elvis

If you need any manual type or non-public documents, you need to get them by mail. We have unified and stored all document information in them. If they also deny file sharing, it’s going to have to be custom made if you want to get what you want.

1 Like
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OK, understood,

thanks :slightly_smiling_face: