wavpack: Clip samples after shifting
It doesn't make much sense to clip pre-shift,
nor is it correct for proper decoding.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
Signed-off-by: Anton Khirnov <anton at khirnov.net>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=365e1ec26d7e89a951ebd7851214f59f4aefdec0
---
libavcodec/wavpack.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
index 11e9904..5358967 100644
--- a/libavcodec/wavpack.c
+++ b/libavcodec/wavpack.c
@@ -405,12 +405,12 @@ static inline int wv_get_value_integer(WavpackFrameContext *s, uint32_t *crc, in
}
bit = (S & s->and) | s->or;
- bit = (((S + bit) << s->shift) - bit);
+ bit = (((S + bit) << s->shift) - bit) << s->post_shift;
if(s->hybrid)
bit = av_clip(bit, -s->hybrid_maxclip, s->hybrid_maxclip - 1);
- return bit << s->post_shift;
+ return bit;
}
static float wv_get_value_float(WavpackFrameContext *s, uint32_t *crc, int S)
C:\>ffmpeg -i 512kbps.wv
ffmpeg version N-36193-gf514695, Copyright (c) 2000-2011 the FFmpeg developers
built on Dec 26 2011 17:50:37 with gcc 4.6.2
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
-enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
libxvid --enable-zlib
libavutil 51. 33.100 / 51. 33.100
libavcodec 53. 48.100 / 53. 48.100
libavformat 53. 28.100 / 53. 28.100
libavdevice 53. 4.100 / 53. 4.100
libavfilter 2. 54.100 / 2. 54.100
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 5.100 / 0. 5.100
libpostproc 51. 2.100 / 51. 2.100
Input #0, wv, from '512kbps.wv':
Duration: 00:00:30.98, start: 0.000000, bitrate: 539 kb/s
Stream #0:0: Audio: wavpack, 48000 Hz, stereo, s32
At least one output file must be specified
The attached sample should be fixed.
It is likely that the code for lossy wavpack is not correct, but without a failing sample, this is unlikely to get fixed.