PCM


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PCM

(communications)

PCM

(data)

PCM

(company)

PCM

(1) See phase change memory.

(2) See also PMC ( programmable metallization cell).

(3) (Plug Compatible Manufacturer) An organization that makes a computer or electronic device that is compatible with an existing machine.

(4) (Pulse Code Modulation) The primary way analog audio signals are converted into digital form by taking samples of the waveforms from 8 to 192 thousand times per second (8 to 192 kHz) and recording each sample as a digital number from 8 to 24 bits long (see sampling). PCM data are pure digital audio samples, and they are the underlying data in several music file formats (see WAV, FLAC and AIFF).

Sound Cards Support PCM
The audio-out port on a sound card provides an analog signal to the speakers; however, compressed formats such as MP3 and AAC are converted to PCM, and the PCM data are converted to analog (see D/A converter). Sound cards may also output PCM and other digital signals such as Dolby Digital (see S/PDIF). With regard to input, an analog microphone is plugged into the audio-in port, and the sound card converts the analog signals to PCM.

PCM Ports on A/V Equipment
When ports on set-top boxes and Blu-ray/DVD players are labeled PCM or linear PCM (LPCM), they refer to uncompressed audio channels rather than encoded formats such as Dolby Digital, TrueHD, DTS and DTS-HD. PCM can be mono, stereo or have multiple channels for surround sound. See Bitstream mode and linear PCM.

It Started With the Telcos
PCM was introduced in the U.S. in the early 1960s when the telephone companies began converting voice to digital for transport over intercity trunks. See mu-Law.


It Starts as PCM
PCM is the primary way analog waves are converted into digital form for voice conversations as well as music. Codecs such as MP3 and AAC that compress the digital data further apply algorithms to the PCM samples in order to eliminate overlapping frequencies as well as sounds that are deemed inaudible to the human ear.


It Starts as PCM
PCM is the primary way analog waves are converted into digital form for voice conversations as well as music. Codecs such as MP3 and AAC that compress the digital data further apply algorithms to the PCM samples in order to eliminate overlapping frequencies as well as sounds that are deemed inaudible to the human ear.


It Starts as PCM
PCM is the primary way analog waves are converted into digital form for voice conversations as well as music. Codecs such as MP3 and AAC that compress the digital data further apply algorithms to the PCM samples in order to eliminate overlapping frequencies as well as sounds that are deemed inaudible to the human ear.







Another Approach to Sampling
Sony's SACD audio format uses Direct Stream Digital (DSD), a dramatic departure from PCM. Instead of turning samples into a number with a range of values, DSD samples are only 1-bit long (0 or 1), depending on whether the wave is moving up or down from the previous sample point (see DSD).
References in periodicals archive ?
Chi-Square test was used to test the significance of each risk factor with the PCM, while logistic regression was utilized to obtain the best fitted model for males and females separately and then collectively through SPSS.
The use of internal endcaps allows the PCM encapsulation tubes to be fitted tightly together, providing for a high packing density and forming roughly triangular spaces around each CPVC pipe where heat transfer fluid can flow.
By making the specific heat of PCM function of temperature, thermal effect of melting and solidification of PCM can be simulated.
The main objective of this work is to determine the applicability of a multilayered approach to model PCM in ESP-r.
Up to now, reliable retention of data has only been shown for single bit-per-cell PCM, whereas no such results on multi-bit PCM have been reported.
In the case of PCMs, the layers of the walls include PCM in addition to the building materials and insulations.
Results: PCM toxicity significantly increased ALT, AST and ALP (321.
The PCM investigational device has the potential to significantly accelerate NuVasive's entry into this important market.
PCM, one of the world's leading manufacturers of positive displacement pumps for the oil and gas, industry and food sectors has announced that its PCM Vulcain all metal progressing cavity pump had reached an important milestone: pumping extremely hot and viscous bitumen for over 20 months in a SAGD (Steam-Assisted Gravity Drainage) trial conducted in Canada by a major oil company.
Researchers have discussed PCM technologies at length, but for the first time, Intel and STMicroelectronics have moved PCM out of the lab and farther toward commercialization.
In documents filed with the Securities and Exchange Commission (SEC), PCM said it no longer owned any stock in The New York Times Co.
the latent heat capacity of wallboard with 30% PCM by weight is about five times greater than the heat uptake of conventional wallboard for a 10[degrees]F (5.