Demosaicing is a process used in digital imaging, including astrophotography, to reconstruct a full-color image from the raw data captured by a camera sensor that uses a color filter array, typically a Bayer filter. The Bayer filter consists of red, green, and blue color filters arranged in a specific pattern over the sensor’s pixels.

In a raw image, each pixel only captures intensity values for one color channel (red, green, or blue) because of the presence of the color filter array. Demosaicing algorithms interpolate the missing color information for each pixel by utilizing the surrounding pixels with different color filters. By analyzing the patterns and relationships between neighboring pixels, the algorithm estimates the full-color values for each pixel.

The demosaicing process helps generate a full-resolution, full-color image that can be further processed and manipulated. It is a crucial step in the overall image processing pipeline for producing accurate and visually appealing final images. Various demosaicing algorithms exist, each with its own strengths and weaknesses, and different software applications or plugins offer different demosaicing options to suit the user’s preferences and specific image characteristics.