Search results
Results from the WOW.Com Content Network
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.
Sample rate Bit rate Bits per sample Latency CBR VBR Stereo Multichannel G.711: companding A-law or μ-law, PCM: 8 kHz 64 kbit/s 8 bit 125 μs (typical) Yes No No No G.711.0: Lossless compression of G.711: 8 kHz 0.2–65.6 kbit/s 8 bit 5–40 ms No Yes No No G.711.1: MDCT, A-law, μ-law: 8, 16 kHz 64, 80, 96 kbit/s 16 bit 11.875 ms Yes Yes No No
For most phonemes, almost all of the energy is contained in the 100 Hz – 4 kHz range, allowing a sampling rate of 8 kHz. This is the sampling rate used by nearly all telephony systems, which use the G.711 sampling and quantization specifications. [citation needed]
Sample-rate conversion prevents changes in speed and pitch that would otherwise occur when transferring recorded material between such systems. More specific types of resampling include: upsampling or upscaling; downsampling, downscaling, or decimation; and interpolation. The term multi-rate digital signal processing is sometimes used to refer ...
The Signal-to-quantization-noise ratio is a multiple of the bit depth. Audio CDs use a bit depth of 16-bits, while DVD-Video and Blu-ray discs can use 24-bit audio. The maximum dynamic range of a 16-bit system is about 96 dB, [9] while for 24 bit it is about 144 dB.
[a] But in signal processing, decimation by a factor of 10 actually means keeping only every tenth sample. This factor multiplies the sampling interval or, equivalently, divides the sampling rate. For example, if compact disc audio at 44,100 samples/second is decimated by a factor of 5/4, the
Uncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44,100 samples/second × 2 channels / 1,000 bits/kilobit), so the bit rates 128, 160, and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively.
In telecommunications and computing, bit rate (bitrate or as a variable R) is the number of bits that are conveyed or processed per unit of time. [1]The bit rate is expressed in the unit bit per second (symbol: bit/s), often in conjunction with an SI prefix such as kilo (1 kbit/s = 1,000 bit/s), mega (1 Mbit/s = 1,000 kbit/s), giga (1 Gbit/s = 1,000 Mbit/s) or tera (1 Tbit/s = 1,000 Gbit/s). [2]