Attention is currently required from: pespin. fixeria has posted comments on this change. ( https://gerrit.osmocom.org/c/libosmocore/+/28176 )
Change subject: coding: add gsm0503_detect_a[fh]s_dtx_frame2() ...................................................................... Patch Set 2: (1 comment) Commit Message: https://gerrit.osmocom.org/c/libosmocore/+/28176/comment/98ae6b67_77c49aad PS2, Line 14: Converting to hard-bits is not really needed. > Why? I see you now moved the conversion inside the implementation. […] Initially I was planning to simplify the code to calculate a sum of all soft-bits, so that we could avoid conditionals in the loops. Basically id_marker[]s would contain multipliers: -1 (for bit 1) and +1 (for bit 0), so then: sum = 0 for (...) sum -= *sbits * id_marker[k]; if (sum >= (n_bits * 127 * 0.8)) /* tolerate up to 20% bit errors */ This works fine, unless you want to calculate BER. You cannot just do: max = n_bits * 127 n_errors = (sum - max) / 127 Because this is not accurate at all. So we still have to convert to hard-bits for the BER calculation. I believe doing this in the same loop (where we match the marker) is better. Also this allows us to handle soft-bit value 0 properly (see my other comment). I can clarify the commit message. -- To view, visit https://gerrit.osmocom.org/c/libosmocore/+/28176 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: libosmocore Gerrit-Branch: master Gerrit-Change-Id: Ibcac395f800bb64150c97fcdaca3523ecfc5fcee Gerrit-Change-Number: 28176 Gerrit-PatchSet: 2 Gerrit-Owner: fixeria <[email protected]> Gerrit-Reviewer: Jenkins Builder Gerrit-CC: pespin <[email protected]> Gerrit-Attention: pespin <[email protected]> Gerrit-Comment-Date: Tue, 24 May 2022 11:44:34 +0000 Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: pespin <[email protected]> Gerrit-MessageType: comment
