[FFmpeg-devel] [PATCH 3/3] avcodec/vaapi: mask unused bits in bitplane_present.value

Jerome Borsboom jerome.borsboom at carpalis.nl
Sun Feb 25 15:23:50 EET 2018

Due to the union construct, unused bits in bitplane_present.value might
be uninitialized even when the used bits are all set to a value.
Masking the unused bits prevents spurious true values when all used
bits are unset, e.g. skipped pictures.

Signed-off-by: Jerome Borsboom <jerome.borsboom at carpalis.nl>
  libavcodec/vaapi_vc1.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/vaapi_vc1.c b/libavcodec/vaapi_vc1.c
index a137979dd4..e93b7285e3 100644
--- a/libavcodec/vaapi_vc1.c
+++ b/libavcodec/vaapi_vc1.c
@@ -387,7 +387,7 @@ static int vaapi_vc1_start_frame(AVCodecContext 
*avctx, av_unused const uint8_t
      if (err)
          goto fail;
  -    if (pic_param.bitplane_present.value) {
+    if (pic_param.bitplane_present.value & 0x7f) {
          uint8_t *bitplane;
          const uint8_t *ff_bp[3];
          int x, y, n;

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