On Mon, Jan 20, 2020 at 08:20:42PM +0100, Andreas Rheinhardt wrote: > Replace "((a << shift) + b) >> shift" by "a + (b >> shift)". This avoids > a left shift which also happens to trigger undefined behaviour in case "a" > is negative. This affected the FATE-tests acodec-adpcm-adx and > acodec-adpcm-adx-trellis; it also fixes ticket #8008. > > Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> > --- > The equivalence of the old code and the new code in the first two > changes is clear from the type of wav[i] (int16_t) and the fact that > COEFF_BITS is 12 (i.e. no high bits are lost when left shifting); for > the last change the equivalence depends upon scale being representable > in an uint16_t. I don't know whether this is indeed so (the direct > estimate gives an upper bound of (2^19 + 2^15 + 1) / 7), but it better > should be so because scale is written via AV_WB16. Maybe it should be > clipped if it is outside of this range? > > libavcodec/adxenc.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-)
will apply patchset thx [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB The misfortune of the wise is better than the prosperity of the fool. -- Epicurus
signature.asc
Description: PGP signature
_______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
