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Comment on An Interview with the Old Man of Floating-Point (1998)parent

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8-bit floating point numbers (in two variants, mu-law and A-law, which differed in the treatment of denormals, A-law was like IEEE floats, mu-law requires a longer explication), about the same as in your choice, have been used for the digitally-encoded telephone audio signals (PCM audio at 8 kHz sampling rate).

They are probably still used in various older communication equipments.

Using floating-point had the purpose to reduce the quantization noise in comparison to 8-bit fixed-point numbers to the level corresponding to 12-bit or 13-bit fixed-point numbers.

So this was effectively a method of compressing by 50% the bit rate of voice signals.

Later, much better audio compression algorithms have been developed, allowing e.g. a 10 times compression, and such algorithms are used in the modern mobile phones.

Nevertheless, 8-bit floating-point was used for many decades in telephony.

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