Make new VDPAU easier to use by adding context to callback.

Using VDPAU correctly means checking for preemption
and possibly regenerating the context all the time.
With the current API there is no context or other
user-defined pointer and thus this in not possible
during decoding unless using some hack like global
variables.
The need to reinitialize both surfaces and even function
pointers makes handling preemption even more difficult.
This patch introduces a new render2 function that gets
both the AVCodecContext and AVFrame in addition,
in both the user can store additional opaque data.
This allows even advanced approaches like keeping a
"generation counter" for the surfaces so they can be
regenerated on the fly and efficiently.
In addition, the function has a return value that will
be passed through all the way instead of being silently
ignored as for the current render function.
Unfortunately the HWAccel API has no way of providing
API/ABI compatibility, so a currently disallowed
state (render pointer being NULL) is used to extend it.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>

1 files changed, 11 insertions, 0 deletions

diff --git a/libavcodec/vdpau.h b/libavcodec/vdpau.h
index 210d517d83..b1c836c4b6 100644
--- a/libavcodec/vdpau.h
+++ b/libavcodec/vdpau.h
@@ -70,6 +70,13 @@ union AVVDPAUPictureInfo {
 };
 #endif
 
+struct AVCodecContext;
+struct AVFrame;
+
+typedef int (*AVVDPAU_Render2)(struct AVCodecContext *, struct AVFrame *,
+                               const VdpPictureInfo *, uint32_t,
+                               const VdpBitstreamBuffer *);
+
 /**
  * This structure is used to share data between the libavcodec library and
  * the client video application.
@@ -129,6 +136,7 @@ typedef struct AVVDPAUContext {
     attribute_deprecated
     VdpBitstreamBuffer *bitstream_buffers;
 #endif
+    AVVDPAU_Render2 render2;
 } AVVDPAUContext;
 
 /**
@@ -138,6 +146,9 @@ typedef struct AVVDPAUContext {
  */
 AVVDPAUContext *av_alloc_vdpaucontext(void);
 
+AVVDPAU_Render2 av_vdpau_hwaccel_get_render2(const AVVDPAUContext *);
+void av_vdpau_hwaccel_set_render2(AVVDPAUContext *, AVVDPAU_Render2);
+
 #if FF_API_CAP_VDPAU
 /** @brief The videoSurface is used for rendering. */
 #define FF_VDPAU_STATE_USED_FOR_RENDER 1