Bit depth

Bit depth

Whenever you look at a screen, whether it’s your phone, your TV, or your laptop, you’re looking at pixels. These pixels light up with specific colors in mind and combine to give you the final picture you’re looking at.

However, not all pixels are equal. As technology has evolved and screens have become more complex, we’re now able to show more colors than ever. And the way this is usually expressed is in terms of the so-called Bit Depth.

Bit depth, also known as color depth, refers to the number of bits used to represent the color or amplitude of each pixel in an image or sound. It determines the amount of information that can be stored for each pixel or audio sample, directly affecting the detail, accuracy, and quality of digital content.

Bit depth is not just limited to screens and images; it also plays a fundamental role in audio. In digital imaging, it represents the amount of information used to define the color of each pixel, often referred to as color depth. For audio, it determines the resolution of sound samples, directly impacting the quality of recordings, mixing, and mastering. This makes bit depth an essential concept for professionals such as graphic designers, who rely on precise color reproduction and smooth gradients, and audio engineers, who need high-resolution sound to ensure clarity and fidelity.

What Is Bit Depth?

Bit depth, also known as color depth, is the number of bits used to indicate the color of a single pixel. It is typically described in bits but can also be expressed in bits-per-channel. The more bits, the higher the precision of colors on a display. Today, most digital displays are at least 24-bit displays, , that is, 8-bit per RGB channel. This means there are 28 = 256 shades of red, 256 shades of green, and 256 shades of blue that can be combined in any way to form a single pixel. In total, this means there are 224 different possible combinations, so over 16.7 million different colors are available.

A 10-bit screen has 210 intensity levels for every color component (or subpixel), so it can reproduce 230 different colors (over a billion). This is particularly important for high-fidelity rendering of high dynamic range and wide color gamut images.

The bit depth of digital images can be even larger than that of current display technology. Cameras often capture photographs with a precision of 12 to 14 bits per sample, with raw formats storing the image data with enough precision to allow adjusting exposure and colors in postproduction.

Bit Depth in Audio

This principle extends to audio as well. The bit depth in digital audio determines the resolution of each sound sample. Higher bit depths allow for capturing more dynamic range and finer nuances, leading to higher-quality recordings. Professionals working with audio are often advised to use the highest possible bit depth to achieve greater resolution, especially during recording, mixing, and mastering stages.

Higher bit depths in audio enable the recording and playback of even the smallest changes in volume and intensity, resulting in clearer and more lifelike sound reproduction. This is particularly important for professional audio engineers during recording, mixing, and mastering, where precision is crucial.

Why Does Bit Depth Matter?

Bit depth is important because it determinesthe available precision of the colors in an image.  For standard gamut, standard dynamic range images, the convention is to use 8 bits per channel (24 bits total). For wide gamut, high dynamic range images, 8-bit is not sufficient and at least 10-bit is needed (30 bits per pixel).

For graphic designers, this ensures that precise color reproduction and smooth gradients can be maintained, which is essential for creating high-quality visual content. Without sufficient bit depth, images might appear washed out or lose important details during editing.

This principle also applies to audio, where a higher bit depth allows for capturing more dynamic range in sound, leading to clearer, more lifelike playback. For example, modern digital audio often uses 24-bit depth to ensure high fidelity.

This is especially important with modern media today. As displays become more advanced, pictures and videos must also keep up with them. A sufficiently high bit depth has to be used in order to avoid image fidelity issues, in particular color banding artifacts.

The same holds true for audio: professionals working with high-end systems rely on high-bit depths to complement the richness and dynamic range of today’s advanced equipment.

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Last updated: Apr 1, 2025