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OzDave
July 7, 2010, 08:57:43
Hi,

I use a firewire DMK31AF03 on MacOSx 10.6.x. I am a software developer and have written some firewire control software for the camera. Being a colour camera, the firewire firmware reports that the camera supports both Colour and Monochrome imaging modes.

The Monochrome mode will provide me with 1024x768 pixel luminance data, while the Colour mode provides me with 1024x768 pixel UYVY (YUV) image data. I have found that if I simply convert the UYVY data to RGB for each pixel, I get a correctly coloured image. I do not have to perform any debayering of the image, which kind of makes sense since YUV is already a colour image format. This makes me think that the camera must be doing the debayering internally and then producing the YUV image data.

So I have several questions:

1) Is the camera delivering me an internally debayered image in this case?

2) If I use the camera in monochrome mode, I assume the output data is simply the Y data from the colour image, with the UV data dropped?

3) Is there a way to get a RAW colour image that would require me to debayer it? There does not appear to be a way to do that with the fireware camera, but I read reports of people using IC Capture on this forum and doing debayering with that or Registax. But I wonder if that is only for the USB models?

Stefan Geissler
July 7, 2010, 09:06:05
Hello,

The DMK is a monochrome camera, that provide only Y800 format. That means, you wont get any color data. If the your software reports that there are color formats, then either the firmware in the camera has been overwritten with a wrong camera type or your driver reports wrong data.

Since the camera is a monochrome camera only, there is absolutely no debayering done. The sensor of the camera has no Bayer Mosaic filter, thus debayering wont work.

OzDave
July 7, 2010, 09:36:17
Sorry, my mistake. The camera is a DFK31AF03.AS. It definitely is a colour camera as I see colour images.

Stefan Geissler
July 7, 2010, 10:01:46
Hello

Thank you for clarifying this, I was really confused.


1) Is the camera delivering me an internally debayered image in this case?
If the UYVY format is in use, then the colors are calculated in the camera.


2) If I use the camera in monochrome mode, I assume the output data is simply the Y data from the colour image, with the UV data dropped?
The Y800 format provides the CCD raw data containing the Bayer Mosaic pattern. In this case, it is not simply the "Y" component. It is real RGB data, each pixel containing only one color component.


3) Is there a way to get a RAW colour image that would require me to debayer it? There does not appear to be a way to do that with the fireware camera, but I read reports of people using IC Capture on this forum and doing debayering with that or Registax. But I wonder if that is only for the USB models?
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Yes, simply use the Y800 video format. For using IC Capture, you may look here too: http://www.astronomycamerasblog.com/2008/05/16/colored-raw-data-uncompressed-y800-capture-registax-import/