Hi,
I’m hoping to get a clarification and probably some references for this. As I’m browsing through CMOS image sensors, I came across with parts with 4-cell CFA just like OV50E from Omnivision. Can anyone give me a guidance on this, does 4-cell CFA in CMOS image sensor means unavoidable 2x2 binning on the HW level? Appreciate the help on this. Thank you.
Greetings,
I would understand the concept of “binning” here to refer to the summation of outputs from adjacent pixels to yield increased photosensitivity in trade for resolution.
Since the whole point of a color filter array is to allow capture of color information by providing separate outputs from pixels with different optical filters, summing them together would seem to defeat the purpose.
As an aside, please be advised that information necessary for development with many image sensor products is held under NDA, and not made available to individuals or small organizations.
Hi Rick,
Appreciate your response to my question. I understand the need for NDA and it’s one of the roadblocks I’m having especially when evaluating parts or understanding product features. For products using RGB, I found products that support several pixel binning, please see below:
I just want to know if image sensors using 4-cell are limited to 2x2 binning and does not support no binning (1x1). Can you share any references, if there’s any? Thank you.
The precise nature of available products varies. Pulling up the image sensor family and filtering for datasheet availability can surface items for which at least basic descriptive information is available. The MT9M114 for example describes subsampling options it offers on or about p.18.
There’s a distinction between “pixel” as an individual (color-filtered) photosensitive element and the minimal collection of such used to return one parcel of color image data. Some care is needed to understand which is referenced in any given instance, but when speaking of binning in color imagers folks are usually talking about combining information from like color channels among adjacent groups.
