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authorJerome Borsboom <jerome.borsboom@carpalis.nl>2018-04-25 20:07:53 +0200
committerPaul B Mahol <onemda@gmail.com>2018-04-25 22:07:20 +0200
commit144ce364cd2df752226115c243d92083291c9355 (patch)
treee74d0672018b3100b01169abe648c62fa7dde76d /libavcodec/vc1.c
parent9ae2845b1c0a358f8585634f443283d560715580 (diff)
downloadffmpeg-144ce364cd2df752226115c243d92083291c9355.tar.gz
avcodec/vc1: more corrections for AC inverse quantization scaling
HALFQP should only be added to the inverse quantizer when the block is coded with PQUANT. When PQUANT is equal to ALTPQUANT, the original test for the addition of HALFQP fails. A negative value for mquant indicates that the value was derived from VOPDQUANT. Fixes #4372 Signed-off-by: Jerome Borsboom <jerome.borsboom@carpalis.nl>
Diffstat (limited to 'libavcodec/vc1.c')
-rw-r--r--libavcodec/vc1.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c
index 5fc479347e..b7050440d5 100644
--- a/libavcodec/vc1.c
+++ b/libavcodec/vc1.c
@@ -991,6 +991,7 @@ int ff_vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb)
v->pquantizer = 1;
break;
}
+ v->dquantfrm = 0;
if (v->postprocflag)
v->postproc = get_bits(gb, 2);