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Digital cameras work on the same principle as film cameras, but the inner functions are quite different. Digital cameras have either a Charge Coupled Device (CCD) or a Complementary Metal-Oxide Semiconductor (CMOS) chip that detects the light image formed by the camera lens. Each sensor element converts light into a voltage equal to the brightness of the image. This then goes into an analogue-to-digital converter (ADC), which translates the fluctuations of the sensor voltage into a binary code. The digital output of the ADC is sent to a digital signal processor, which adjusts the colour, contrast and detail to produce a pleasing image, encodes the image using a standard colour encoding (typically sRGB) and compresses the image before sending it to the storage place (internal storage or memory card).
Assessing performance and describing colour reproduction in and through digital cameras is facilitated by the standardized measurement methods provided by IEC. Both still (non-moving) and moving image cameras can be characterized using such standardized tests and measurements.