[FFmpeg-devel] [PATCH] FLAC parser

Uoti Urpala uoti.urpala
Sun Mar 29 03:10:07 CEST 2009

On Sat, 2009-03-28 at 21:00 -0400, Justin Ruggles wrote:
> How do you calculate how many bits are checked for 1 invalid value in a
> 4-bit code? 2 invalid values in a 3-bit code? etc...

In this context you can use the base 2 logarithm of the probability of a
mistake going undetected.
For 1 invalid value in 4-bit code, -ln(15/16)/ln(2) = 0.093
For 2 invalid values in a 3-bit code, -ln(6/8)/ln(2) = 0.415

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