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NNTP-Posting-Date: Tue, 24 Nov 2020 16:20:34 -0600
From: Randy Yates <yates@digitalsignallabs.com>
Newsgroups: comp.dsp
Subject: BCH Encoding/Decoding
Date: Tue, 24 Nov 2020 17:20:34 -0500
Message-ID: <87d0025rd9.fsf@digitalsignallabs.com>
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Xref: csiph.com comp.dsp:35299

I've notieced that in order to decode a page of in-band data, the linux
kernel code first computes the out-of-band ECC bytes on the given
in-band data (calc_ecc). It is also passed the received oob data
recv_ecc. 

If (byte-by-byte) the calc_ecc does not match the recv_data, then
the page is decoded. 

Why not compute the decoded ECC and compute the locator
vector/polynomial right off? Are these operations much
more expensive than encoding and comparing?

--Randyh