From afd930dca23adad09ffbf6f9ff35b7258047895a 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() (cherry picked from commit 83e31db195b9d0a07b0526eab5780817d8ce9444) Signed-off-by: Michael Niedermayer --- libavcodec/wmalosslessdec.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/libavcodec/wmalosslessdec.c b/libavcodec/wmalosslessdec.c index a60f477089..8f7f290548 100644 --- a/libavcodec/wmalosslessdec.c +++ b/libavcodec/wmalosslessdec.c @@ -757,6 +757,23 @@ 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