[FFmpeg-devel] [PATCH] [dxva2] Handle return value of BeginFrame better for nVidia cards.

[Lars Hammarstrand]

https://github.com/FlyingRat/FFmpeg/commit/1aba762826b074b40f963708ea8780681f436c4b

The nVidia cards sometimes return E_PENDING and need time before they
can start decoding a new frame.

Helps nVidia cards with blocky pictures/pixellation artifacts after skip
or when CPU is busy.
---
 libavcodec/dxva2.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/libavcodec/dxva2.c b/libavcodec/dxva2.c
index 0997c73..25e5b0b 100644
--- a/libavcodec/dxva2.c
+++ b/libavcodec/dxva2.c
@@ -21,6 +21,8 @@
  */

 #include "dxva2_internal.h"
+#include <unistd.h>
+#define MAX_RETRY_ON_PENDING           50

 void *ff_dxva2_get_surface(const Picture *picture)
 {
@@ -88,10 +90,17 @@ int ff_dxva2_common_end_frame(AVCodecContext *avctx,
Picture *pic,
     DXVA2_DecodeBufferDesc buffer[4];
     DXVA2_DecodeExecuteParams exec = { 0 };
     int      result;
+    HRESULT  hr;
+    int      tries = 0;

-    if (FAILED(IDirectXVideoDecoder_BeginFrame(ctx->decoder,
+    while ((hr=IDirectXVideoDecoder_BeginFrame(ctx->decoder,
                                                ff_dxva2_get_surface(pic),
-                                               NULL))) {
+                                               NULL)) == E_PENDING
+           && tries < MAX_RETRY_ON_PENDING) {
+        usleep(1000);
+        tries++;
+    }
+    if (FAILED(hr)) {
         av_log(avctx, AV_LOG_ERROR, "Failed to begin frame\n");
         return -1;
     }
--
1.8.0.1