From 0faae518e927b791e86f5a43b919a5c6e882d9b5 Mon Sep 17 00:00:00 2001 From: Mashiat Sarker Shakkhar Date: Sun, 6 Nov 2011 03:02:11 +0600 Subject: [PATCH] Implement lms_predict() --- libavcodec/wmalosslessdec.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/libavcodec/wmalosslessdec.c b/libavcodec/wmalosslessdec.c index 5c6eed1744..eafe145aae 100644 --- a/libavcodec/wmalosslessdec.c +++ b/libavcodec/wmalosslessdec.c @@ -754,6 +754,23 @@ static void reset_codec(WmallDecodeCtx *s) +static int lms_predict(WmallDecodeCtx *s, int ich, int ilms) +{ + int32_t pred, icoef; + int recent = s->cdlms[ich][ilms].recent; + + for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++) + pred += s->cdlms[ich][ilms].coefs[icoef] * + s->cdlms[ich][ilms].lms_prevvalues[icoef + recent]; + + pred += (1 << (s->cdlms[ich][ilms].scaling - 1)); + /* XXX: Table 29 has: + iPred >= cdlms[iCh][ilms].scaling; + seems to me like a missing > */ + pred >>= s->cdlms[ich][ilms].scaling; + return pred; +} + /** *@brief Decode a single subframe (block). *@param s codec context