Channel (digital image)

Color digital images are made of pixels, and pixels are made of combinations of primary colors represented by a series of code. A channel in this context is the grayscale image of the same size as a color image, made of just one of these primary colors. For instance, an image from a standard digital camera will have a red, green and blue channel. A grayscale image has just one channel.A 24-bit RGB imageThe RED channel of the original RGB image (converted to greyscale for easier viewing)The GREEN channel of the original RGB image (converted to greyscale for easier viewing)The BLUE channel of the original RGB image (converted to greyscale for easier viewing)A 32-bit CMYK imageThe CYAN channel of the original CMYK imageThe MAGENTA channel of the original CMYK imageThe YELLOW channel of the original CMYK imageThe KEY (black) channel of the original CMYK image Color digital images are made of pixels, and pixels are made of combinations of primary colors represented by a series of code. A channel in this context is the grayscale image of the same size as a color image, made of just one of these primary colors. For instance, an image from a standard digital camera will have a red, green and blue channel. A grayscale image has just one channel. In geographic information systems, channels are often referred to as raster bands. Another closely related concept is feature maps, which are used in convolutional neural networks.