PCM (Pulse-Code Modulation) is the raw, uncompressed representation of digital audio: a stream of sample values, one per channel per tick of the sample clock. It is what an ADC produces and what a DAC consumes, the common denominator every codec encodes from and decodes back to. WAV and AIFF files are mostly just PCM with a header; professional IP links (AES67, SMPTE ST 2110-30) and SDI embed PCM directly. Its size is simple to predict — sample rate times bit depth times channels — so 48 kHz, 24-bit stereo is about 2.3 Mbit/s, which is why delivery almost always compresses it.
The book · Volume 4 of 7
Audio for Video: A Complete Guide to Sound in Video Products: From PCM and Codecs to Loudness, Accessibility, and Real-Time Voice Processing
PCM is the raw format every capture card, codec and DAC speaks, so mistakes in sample format or channel order propagate everywhere. This volume covers PCM in depth with sampling, bit depth, dynamic range and channel layouts, giving you a solid base for every encode, mix and conversion step. Written by Nikolay Sapunov, CEO at Fora Soft.
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