From a548b6cbfcf6d872bed473c1981931db36eda690 Mon Sep 17 00:00:00 2001 From: Derek Buitenhuis Date: Sat, 3 Dec 2011 14:35:23 -0500 Subject: wavpack: Properly clip samples during lossy decode When decoding lossy WavPack samples, they are supposed to be clipped, in order to be decoded correctly. Signed-off-by: Derek Buitenhuis Signed-off-by: Ronald S. Bultje --- libavcodec/wavpack.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'libavcodec/wavpack.c') diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c index e4b7ebe43b..11e9904983 100644 --- a/libavcodec/wavpack.c +++ b/libavcodec/wavpack.c @@ -110,7 +110,7 @@ typedef struct WavpackFrameContext { int extra_bits; int and, or, shift; int post_shift; - int hybrid, hybrid_bitrate; + int hybrid, hybrid_bitrate, hybrid_maxclip; int float_flag; int float_shift; int float_max_exp; @@ -403,8 +403,14 @@ static inline int wv_get_value_integer(WavpackFrameContext *s, uint32_t *crc, in *crc = *crc * 9 + (S&0xffff) * 3 + ((unsigned)S>>16); } } + bit = (S & s->and) | s->or; - return (((S + bit) << s->shift) - bit) << s->post_shift; + bit = (((S + bit) << s->shift) - bit); + + if(s->hybrid) + bit = av_clip(bit, -s->hybrid_maxclip, s->hybrid_maxclip - 1); + + return bit << s->post_shift; } static float wv_get_value_float(WavpackFrameContext *s, uint32_t *crc, int S) @@ -792,6 +798,7 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no, s->joint = s->frame_flags & WV_JOINT_STEREO; s->hybrid = s->frame_flags & WV_HYBRID_MODE; s->hybrid_bitrate = s->frame_flags & WV_HYBRID_BITRATE; + s->hybrid_maxclip = 1 << ((((s->frame_flags & 0x03) + 1) << 3) - 1); s->post_shift = 8 * (bpp-1-(s->frame_flags&0x03)) + ((s->frame_flags >> 13) & 0x1f); s->CRC = AV_RL32(buf); buf += 4; if(wc->mkv_mode) -- cgit v1.2.3