enkanalsbilder

Enkanalsbilder, or single-channel images, are digital images in which each pixel is represented by a single numeric value that corresponds to an intensity measurement. Unlike color images that store multiple channels per pixel (for example RGB with three channels, or RGBA with four), enkanalsbilder contain only one channel. The most common form is grayscale images where the channel encodes brightness from black to white. Other single-channel forms include depth maps from stereo or structured-light systems, thermal infrared images, and certain medical or scientific images.

Data representation: a grayscale image is typically stored as a two-dimensional array of size height by width, with pixel values often 8-bit (0–255) or 16-bit (0–65535). In some processing pipelines, images may be stored as a three-dimensional array with a singleton third dimension. Range can be linear or normalized to [0, 1].

Acquisition and processing: single-channel data can be obtained directly from a dedicated sensor or derived from a color image by luminance calculation using weighted sums of the RGB channels. Common luminance weights include 0.299, 0.587, and 0.114 (ITU-R BT.601).

Applications and advantages: fewer data to store and process, faster algorithms for tasks like edge detection, segmentation, or depth estimation. Grayscale is often a pre-processing step before colorization or when color information is unnecessary.

Formats and interoperability: many image file formats support single-channel data, including PNG, TIFF, and JPEG (grayscale). Some formats distinguish planar versus interleaved storage.

Challenges: preserving perceptual contrast, proper gamma handling, and maintaining precision in high-dynamic-range or scientific imagery.