![\"Bit](\"https:\/\/www.japanistry.com\/wp-content\/uploads\/2017\/09\/Tonal-Bits-v01.jpg\")
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bit depth<\/p>\n
![\"BIT](\"https:\/\/i.ytimg.com\/vi\/fk_QLRaOiZM\/maxresdefault.jpg\")
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is the amount of information per discrete signal (sample) of a digital signal, that is, the number of quantization bits. Bit depth is only significant for PCM audio. There is no concept of bit depth in lossy compressed non-PCM audio such as MP3 and AAC. It is a term used in audio and graphics, and this section describes it in digital audio. == PCM Audio Bit Depth == There are several methods of recording digital audio, but most commonly used on CD-DA , DVD , computers , etc. is the pulse code modulation (PCM) method. In PCM, when the sound pressure bit depth is reduced at intervals of tens of thousands of times per second, the error between the original sound and the approximate recorded value becomes large, and it becomes difficult to faithfully reproduce the sound pressure waveform. original sound. The error is called the quantization error, and when the error tends to be large, such as 8 bits (256 steps), it can be heard by the human ear as noise. * CD-DA<\/p>\n
(electrical voltage) at intervals of tens of thousands of times per second and records (displays) it discretely digitally, but the quantization accuracy is high and depends on the bit depth. Since digital numbers are recorded in binary and digits are bit deep, the number of recordable steps is calculated by multiplying by 2 bits deep.<\/p>\n
It has a standard bit depth of 16 bits and a dynamic range of approximately 96 dB.
\n* DVD audio supports a bit depth of 24 bits per standard and has a dynamic range of approximately 144 dB.
\nIn the field of acoustic engineering, when expressing the reproduction accuracy of sound amplitude, the ratio of the minimum and maximum values \u200b\u200bthat can be reproduced is expressed as a dynamic range in units of decibels (dB), which is a scale logarithmic . The dynamic range at a given bit depth can be calculated using the following formula ( audio compression and the case of uncompressed linear PCM which does not consider compression
\nDR_ = 20log_ (2^n), Or simply DR_ = 6.02n
\nThe human ear is said to have a dynamic range of 120 dB and the ability to perceive frequencies from 20 to 20,000 hertz (Hz). Therefore, a bit depth of about 24 bits is said to be required to faithfully reproduce sound as long as it is not inferior to human hearing. For example, some music DVD standards are for 24-bit\/96 kHz DTS tracks. In reality, however, no audio device has ever achieved a theoretical noise floor (-144.50 dB) at 24-bit depth. If you have a practical dynamic range (about 110 dB), you can handle noise other than 24-bit quantization noise.<\/p>\n","protected":false},"excerpt":{"rendered":"