qsv: Join the derived session to the parent

Should improve the performance on multiple transcoding from a single
source.

1 files changed, 5 insertions, 0 deletions

diff --git a/libavcodec/qsv.c b/libavcodec/qsv.c
index a8ae65622c..96dca14e9a 100644
--- a/libavcodec/qsv.c
+++ b/libavcodec/qsv.c
@@ -593,6 +593,11 @@ int ff_qsv_init_session_device(AVCodecContext *avctx, mfxSession *psession,
                                       "Error setting a HW handle");
     }
 
+    err = MFXJoinSession(parent_session, session);
+    if (err != MFX_ERR_NONE)
+        return ff_qsv_print_error(avctx, err,
+                                  "Error joining session");
+
     ret = qsv_load_plugins(session, load_plugins, avctx);
     if (ret < 0) {
         av_log(avctx, AV_LOG_ERROR, "Error loading plugins\n");