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author | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | 2020-01-20 20:20:43 +0100 |
---|---|---|
committer | Michael Niedermayer <michael@niedermayer.cc> | 2020-01-21 10:01:46 +0100 |
commit | 340e6b018596837db950e82b4d5232d993e23934 (patch) | |
tree | 3b936305c2241548fcad27ecce122987fb97b393 | |
parent | 59a9d65e0d790821f88527a82569f56eb2f8a9be (diff) |
avcodec/adxdec: Remove unnecessary left-shift
Replace "(a * (1 << shift) * b + c) >> shift" by "a * b + (c >> shift)".
It is equivalent to the old code because a is in the range of uint16_t,
shift is 12 and b is effectively a signed 4-bit number, so that no
overflow/truncation of high bits happens during the multiplication
(overflow would be undefined anyway).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
-rw-r--r-- | libavcodec/adxdec.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/libavcodec/adxdec.c b/libavcodec/adxdec.c index 178ea99dcf..40ed8e5ba7 100644 --- a/libavcodec/adxdec.c +++ b/libavcodec/adxdec.c @@ -81,7 +81,7 @@ static int adx_decode(ADXContext *c, int16_t *out, int offset, s2 = prev->s2; for (i = 0; i < BLOCK_SAMPLES; i++) { d = get_sbits(&gb, 4); - s0 = ((d * (1 << COEFF_BITS)) * scale + c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS; + s0 = d * scale + ((c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS); s2 = s1; s1 = av_clip_int16(s0); *out++ = s1; |