Search results
Results from the WOW.Com Content Network
The number of possible values that an integer bit depth can represent can be calculated by using 2 n, where n is the bit depth. [1] Thus, a 16-bit system has a resolution of 65,536 (2 16) possible values. Integer PCM audio data is typically stored as signed numbers in two's complement format. [2]
The audio bit rate for a Red Book audio CD is 1,411,200 bits per second (1,411 kbit/s) or 176,400 bytes per second; 2 channels × 44,100 samples per second per channel × 16 bits per sample. Audio data coming in from a CD is contained in sectors, each sector being 2,352 bytes, and with 75 sectors containing 1 second of audio.
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, [10] while for 24 bit it is about 144 dB.
Ultimately Sony prevailed on both sample rate (44.1 kHz) and bit depth (16 bits per sample, rather than 14 bits per sample). The technical reasoning behind the rate being chosen is associated with characteristics of human hearing and early digital audio recording systems as described below. [1]: sec. 8.5
Using this technique, the audio data is stored as a sequence of fixed amplitude (i.e. 1-bit) values at a sample rate of 2.884 MHz, which is 64 times the 44.1 kHz sample rate used by CD. At any point in time, the amplitude of the original analog signal is represented by the density of 1's or 0's in the data stream.
For example, Compact Disc Digital Audio and Digital Audio Tape systems use different sampling rates, and American television, European television, and movies all use different frame rates. Sample-rate conversion prevents changes in speed and pitch that would otherwise occur when transferring recorded material between such systems.
CD + Extended Graphics (CD+EG, also known as CD+XG) is an improved variant of the Compact Disc + Graphics (CD+G) format. Like CD+G, CD+EG uses basic CD-ROM features to display text and video information in addition to the music being played.
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