From dd4fb2339f76a958bd7e63e5ac18b8c10852ae1a Mon Sep 17 00:00:00 2001 From: Luca Barbato Date: Thu, 21 Apr 2016 16:09:38 +0200 Subject: [PATCH] ape: Unbreak adaptcoeffs computation And simplify and explain the expression. Fault introduced in f3fdef108eb06b1e71b29152bf6822519e787efe Signed-off-by: Derek Buitenhuis --- libavcodec/apedec.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c index b028e94ad2..1e89a7bdb1 100644 --- a/libavcodec/apedec.c +++ b/libavcodec/apedec.c @@ -1284,8 +1284,16 @@ static void do_apply_filter(APEContext *ctx, int version, APEFilter *f, /* Update the adaption coefficients */ absres = FFABS(res); if (absres) - *f->adaptcoeffs = ((res & INT32_MIN) ^ ((~0UL) << 30)) >> - (25 + (absres <= f->avg*3) + (absres <= f->avg*4/3)); + *f->adaptcoeffs = APESIGN(res) * + (8 << ((absres > f->avg * 3) + (absres > f->avg * 4 / 3))); + /* equivalent to the following code + if (absres <= f->avg * 4 / 3) + *f->adaptcoeffs = APESIGN(res) * 8; + else if (absres <= f->avg * 3) + *f->adaptcoeffs = APESIGN(res) * 16; + else + *f->adaptcoeffs = APESIGN(res) * 32; + */ else *f->adaptcoeffs = 0;