Definition of Audio bit depth
In digital audio using pulse-code modulation (PCM), bit depth is the number of bits of information in each sample, and it directly corresponds to the resolution of each sample. Examples of bit depth include CD-DA and DVD-Video, which use 16 bits per sample, and DVD-Audio and Blu-ray Disc, which can support up to 24 bits per sample.
In basic implementations, variations in bit depth primarily affect the noise level from quantization error—thus the signal-to-noise ratio (SNR) and dynamic range. However, techniques such as dithering, noise shaping, and oversampling can mitigate these effects without changing the bit depth. Bit depth also affects bit rate and file size.
Bit depth is useful for describing PCM digital signals. Non-PCM formats, such as those using lossy compression, do not have associated bit depths.
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Questions people ask
Real questions from the Stack Exchange community – follow a link to read the discussion.
- What is the proper way to reduce audio sample rate and bit depth? · Sound Design SE
- What do I lose when reducing bit depth? · Sound Design SE
- What sampling rate and bit depth would be necessary to make a digital recording indistinguishable from the original? · Sound Design SE
- Should I ever use a bit depth less than 24 bits? · Sound Design SE
- The relationship between bit depth and SNR in ADC · Electronics SE
Frequently asked questions
What is Audio bit depth?
In digital audio using pulse-code modulation (PCM), bit depth is the number of bits of information in each sample, and it directly corresponds to the resolution of each sample.
Sources & credits
- Wikipedia: Audio bit depth – CC BY-SA 4.0
- Image by Aquegg – CC BY-SA 3.0