lavc: vdpau: Add support for new hw_frames_ctx and hw_device_ctx API

This supports retrieving the device from a provided hw_frames_ctx, and
automatically creating a hw_frames_ctx if hw_device_ctx is set.

The old API is not deprecated yet. The user can still use
av_vdpau_bind_context() (with or without setting hw_frames_ctx), or use
the API before that by allocating and setting hwaccel_context manually.

Cherry-picked from Libav commit 1a7ddba5.
(Adds missing APIchanges entry to the Libav version.)

Reviewed-by: Mark Thompson <sw@jkqxz.net>

doc/APIchanges

@@ -15,6 +15,11 @@ libavutil:     2015-08-28
 
 API changes, most recent first:
 
+2017-03-xx - xxxxxxx - lavc 57.85.101 - avcodec.h
+  vdpau hardware accelerated decoding now supports the new hwaccel API, which
+  can create the decoder context and allocate hardware frame automatically.
+  See AVCodecContext.hw_device_ctx and AVCodecContext.hw_frames_ctx.
+
 2017-03-xx - xxxxxxx - lavc 57.85.100 - avcodec.h
   Add AVCodecContext.hwaccel_flags field. This will control some hwaccels at
   a later point.

libavcodec/vdpau.c

@@ -138,34 +138,75 @@ int ff_vdpau_common_init(AVCodecContext *avctx, VdpDecoderProfile profile,
     vdctx->width            = UINT32_MAX;
     vdctx->height           = UINT32_MAX;
 
-    if (!hwctx) {
-        vdctx->device  = VDP_INVALID_HANDLE;
-        av_log(avctx, AV_LOG_WARNING, "hwaccel_context has not been setup by the user application, cannot initialize\n");
-        return 0;
-    }
+    if (av_vdpau_get_surface_parameters(avctx, &type, &width, &height))
+        return AVERROR(ENOSYS);
 
-    if (hwctx->context.decoder != VDP_INVALID_HANDLE) {
-        vdctx->decoder = hwctx->context.decoder;
-        vdctx->render  = hwctx->context.render;
-        vdctx->device  = VDP_INVALID_HANDLE;
-        return 0; /* Decoder created by user */
-    }
-    hwctx->reset            = 0;
+    if (hwctx) {
+        hwctx->reset            = 0;
 
-    vdctx->device           = hwctx->device;
-    vdctx->get_proc_address = hwctx->get_proc_address;
+        if (hwctx->context.decoder != VDP_INVALID_HANDLE) {
+            vdctx->decoder = hwctx->context.decoder;
+            vdctx->render  = hwctx->context.render;
+            vdctx->device  = VDP_INVALID_HANDLE;
+            return 0; /* Decoder created by user */
+        }
 
-    if (hwctx->flags & AV_HWACCEL_FLAG_IGNORE_LEVEL)
-        level = 0;
-    else if (level < 0)
-        return AVERROR(ENOTSUP);
+        vdctx->device           = hwctx->device;
+        vdctx->get_proc_address = hwctx->get_proc_address;
+
+        if (hwctx->flags & AV_HWACCEL_FLAG_IGNORE_LEVEL)
+            level = 0;
+
+        if (!(hwctx->flags & AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH) &&
+            type != VDP_CHROMA_TYPE_420)
+            return AVERROR(ENOSYS);
+    } else {
+        AVHWFramesContext *frames_ctx = NULL;
+        AVVDPAUDeviceContext *dev_ctx;
+
+        // We assume the hw_frames_ctx always survives until ff_vdpau_common_uninit
+        // is called. This holds true as the user is not allowed to touch
+        // hw_device_ctx, or hw_frames_ctx after get_format (and ff_get_format
+        // itself also uninits before unreffing hw_frames_ctx).
+        if (avctx->hw_frames_ctx) {
+            frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+        } else if (avctx->hw_device_ctx) {
+            int ret;
+
+            avctx->hw_frames_ctx = av_hwframe_ctx_alloc(avctx->hw_device_ctx);
+            if (!avctx->hw_frames_ctx)
+                return AVERROR(ENOMEM);
+
+            frames_ctx            = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+            frames_ctx->format    = AV_PIX_FMT_VDPAU;
+            frames_ctx->sw_format = avctx->sw_pix_fmt;
+            frames_ctx->width     = avctx->coded_width;
+            frames_ctx->height    = avctx->coded_height;
+
+            ret = av_hwframe_ctx_init(avctx->hw_frames_ctx);
+            if (ret < 0) {
+                av_buffer_unref(&avctx->hw_frames_ctx);
+                return ret;
+            }
+        }
 
-    if (av_vdpau_get_surface_parameters(avctx, &type, &width, &height))
-        return AVERROR(ENOSYS);
+        if (!frames_ctx) {
+            av_log(avctx, AV_LOG_ERROR, "A hardware frames context is "
+                   "required for VDPAU decoding.\n");
+            return AVERROR(EINVAL);
+        }
 
-    if (!(hwctx->flags & AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH) &&
-        type != VDP_CHROMA_TYPE_420)
-        return AVERROR(ENOSYS);
+        dev_ctx = frames_ctx->device_ctx->hwctx;
+
+        vdctx->device           = dev_ctx->device;
+        vdctx->get_proc_address = dev_ctx->get_proc_address;
+
+        if (avctx->hwaccel_flags & AV_HWACCEL_FLAG_IGNORE_LEVEL)
+            level = 0;
+    }
+
+    if (level < 0)
+        return AVERROR(ENOTSUP);
 
     status = vdctx->get_proc_address(vdctx->device,
                                      VDP_FUNC_ID_VIDEO_SURFACE_QUERY_CAPABILITIES,
@@ -263,7 +304,7 @@ static int ff_vdpau_common_reinit(AVCodecContext *avctx)
     if (vdctx->device == VDP_INVALID_HANDLE)
         return 0; /* Decoder created by user */
     if (avctx->coded_width == vdctx->width &&
-        avctx->coded_height == vdctx->height && !hwctx->reset)
+        avctx->coded_height == vdctx->height && (!hwctx || !hwctx->reset))
         return 0;
 
     avctx->hwaccel->uninit(avctx);
@@ -295,15 +336,17 @@ int ff_vdpau_common_end_frame(AVCodecContext *avctx, AVFrame *frame,
 
 #if FF_API_BUFS_VDPAU
 FF_DISABLE_DEPRECATION_WARNINGS
+    if (hwctx) {
     av_assert0(sizeof(hwctx->info) <= sizeof(pic_ctx->info));
     memcpy(&hwctx->info, &pic_ctx->info, sizeof(hwctx->info));
     hwctx->bitstream_buffers = pic_ctx->bitstream_buffers;
     hwctx->bitstream_buffers_used = pic_ctx->bitstream_buffers_used;
     hwctx->bitstream_buffers_allocated = pic_ctx->bitstream_buffers_allocated;
+    }
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif
 
-    if (!hwctx->render && hwctx->render2) {
+    if (hwctx && !hwctx->render && hwctx->render2) {
         status = hwctx->render2(avctx, frame, (void *)&pic_ctx->info,
                                 pic_ctx->bitstream_buffers_used, pic_ctx->bitstream_buffers);
     } else
@@ -315,9 +358,11 @@ FF_ENABLE_DEPRECATION_WARNINGS
 
 #if FF_API_BUFS_VDPAU
 FF_DISABLE_DEPRECATION_WARNINGS
+    if (hwctx) {
     hwctx->bitstream_buffers = NULL;
     hwctx->bitstream_buffers_used = 0;
     hwctx->bitstream_buffers_allocated = 0;
+    }
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif
 

libavcodec/vdpau_internal.h

@@ -28,6 +28,8 @@
 #include <vdpau/vdpau.h>
 
 #include "libavutil/frame.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/hwcontext_vdpau.h"
 
 #include "avcodec.h"
 #include "vdpau.h"

libavcodec/version.h

@@ -29,7 +29,7 @@
 
 #define LIBAVCODEC_VERSION_MAJOR  57
 #define LIBAVCODEC_VERSION_MINOR  85
-#define LIBAVCODEC_VERSION_MICRO 100
+#define LIBAVCODEC_VERSION_MICRO 101
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \