[FFmpeg-devel] lavc/amfenc: moving amf common code (library and context) to

Submitted by Alexander Kravchenko on May 8, 2018, 10:41 a.m.

Details

Message ID 20180508104125.44304-1-akravchenko188@gmail.com
State New
Headers show

Commit Message

Alexander Kravchenko May 8, 2018, 10:41 a.m.
This patch moves AMF common parts from amfenc to hwcontext_amf.
Now av_hwdevice_ctx API is used for AMF context creation/destroying
This patch does not change component behaviour, 
it contains only restructurization for further patches with new amf components

---
sending patch one more time in May, since April's one wasn't commented/pushed.
previous April's link:
http://ffmpeg.org/pipermail/ffmpeg-devel/2018-April/229051.html



 libavcodec/amfenc.c            | 250 ++++---------------------------
 libavcodec/amfenc.h            |  27 +---
 libavutil/Makefile             |   2 +
 libavutil/hwcontext.c          |   4 +
 libavutil/hwcontext.h          |   1 +
 libavutil/hwcontext_amf.c      | 329 +++++++++++++++++++++++++++++++++++++++++
 libavutil/hwcontext_amf.h      |  43 ++++++
 libavutil/hwcontext_internal.h |   1 +
 8 files changed, 418 insertions(+), 239 deletions(-)
 create mode 100644 libavutil/hwcontext_amf.c
 create mode 100644 libavutil/hwcontext_amf.h

Patch hide | download patch | download mbox

diff --git a/libavcodec/amfenc.c b/libavcodec/amfenc.c
index 384d8efc92..a8186c7b86 100644
--- a/libavcodec/amfenc.c
+++ b/libavcodec/amfenc.c
@@ -21,13 +21,7 @@ 
 #include "libavutil/avassert.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/hwcontext.h"
-#if CONFIG_D3D11VA
-#include "libavutil/hwcontext_d3d11va.h"
-#endif
-#if CONFIG_DXVA2
-#define COBJMACROS
-#include "libavutil/hwcontext_dxva2.h"
-#endif
+
 #include "libavutil/mem.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/time.h"
@@ -35,14 +29,12 @@ 
 #include "amfenc.h"
 #include "internal.h"
 
-#if CONFIG_D3D11VA
-#include <d3d11.h>
+#if CONFIG_DXVA2
+#include <d3d9.h>
 #endif
 
-#ifdef _WIN32
-#include "compat/w32dlfcn.h"
-#else
-#include <dlfcn.h>
+#if CONFIG_D3D11VA
+#include <d3d11.h>
 #endif
 
 #define FFMPEG_AMF_WRITER_ID L"ffmpeg_amf"
@@ -88,34 +80,17 @@  static enum AMF_SURFACE_FORMAT amf_av_to_amf_format(enum AVPixelFormat fmt)
     return AMF_SURFACE_UNKNOWN;
 }
 
-static void AMF_CDECL_CALL AMFTraceWriter_Write(AMFTraceWriter *pThis,
-    const wchar_t *scope, const wchar_t *message)
-{
-    AmfTraceWriter *tracer = (AmfTraceWriter*)pThis;
-    av_log(tracer->avctx, AV_LOG_DEBUG, "%ls: %ls", scope, message); // \n is provided from AMF
-}
 
-static void AMF_CDECL_CALL AMFTraceWriter_Flush(AMFTraceWriter *pThis)
-{
-}
-
-static AMFTraceWriterVtbl tracer_vtbl =
-{
-    .Write = AMFTraceWriter_Write,
-    .Flush = AMFTraceWriter_Flush,
-};
-
-static int amf_load_library(AVCodecContext *avctx)
+static int amf_init_context(AVCodecContext *avctx)
 {
-    AmfContext        *ctx = avctx->priv_data;
-    AMFInit_Fn         init_fun;
-    AMFQueryVersion_Fn version_fun;
-    AMF_RESULT         res;
+    AmfContext *ctx = avctx->priv_data;
+    av_unused int ret;
 
     ctx->delayed_frame = av_frame_alloc();
     if (!ctx->delayed_frame) {
         return AVERROR(ENOMEM);
     }
+    
     // hardcoded to current HW queue size - will realloc in timestamp_queue_enqueue() if too small
     ctx->timestamp_list = av_fifo_alloc((avctx->max_b_frames + 16) * sizeof(int64_t));
     if (!ctx->timestamp_list) {
@@ -123,119 +98,9 @@  static int amf_load_library(AVCodecContext *avctx)
     }
     ctx->dts_delay = 0;
 
-
-    ctx->library = dlopen(AMF_DLL_NAMEA, RTLD_NOW | RTLD_LOCAL);
-    AMF_RETURN_IF_FALSE(ctx, ctx->library != NULL,
-        AVERROR_UNKNOWN, "DLL %s failed to open\n", AMF_DLL_NAMEA);
-
-    init_fun = (AMFInit_Fn)dlsym(ctx->library, AMF_INIT_FUNCTION_NAME);
-    AMF_RETURN_IF_FALSE(ctx, init_fun != NULL, AVERROR_UNKNOWN, "DLL %s failed to find function %s\n", AMF_DLL_NAMEA, AMF_INIT_FUNCTION_NAME);
-
-    version_fun = (AMFQueryVersion_Fn)dlsym(ctx->library, AMF_QUERY_VERSION_FUNCTION_NAME);
-    AMF_RETURN_IF_FALSE(ctx, version_fun != NULL, AVERROR_UNKNOWN, "DLL %s failed to find function %s\n", AMF_DLL_NAMEA, AMF_QUERY_VERSION_FUNCTION_NAME);
-
-    res = version_fun(&ctx->version);
-    AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_QUERY_VERSION_FUNCTION_NAME, res);
-    res = init_fun(AMF_FULL_VERSION, &ctx->factory);
-    AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_INIT_FUNCTION_NAME, res);
-    res = ctx->factory->pVtbl->GetTrace(ctx->factory, &ctx->trace);
-    AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "GetTrace() failed with error %d\n", res);
-    res = ctx->factory->pVtbl->GetDebug(ctx->factory, &ctx->debug);
-    AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "GetDebug() failed with error %d\n", res);
-    return 0;
-}
-
-#if CONFIG_D3D11VA
-static int amf_init_from_d3d11_device(AVCodecContext *avctx, AVD3D11VADeviceContext *hwctx)
-{
-    AmfContext *ctx = avctx->priv_data;
-    AMF_RESULT res;
-
-    res = ctx->context->pVtbl->InitDX11(ctx->context, hwctx->device, AMF_DX11_1);
-    if (res != AMF_OK) {
-        if (res == AMF_NOT_SUPPORTED)
-            av_log(avctx, AV_LOG_ERROR, "AMF via D3D11 is not supported on the given device.\n");
-        else
-            av_log(avctx, AV_LOG_ERROR, "AMF failed to initialise on the given D3D11 device: %d.\n", res);
-        return AVERROR(ENODEV);
-    }
-
-    return 0;
-}
-#endif
-
-#if CONFIG_DXVA2
-static int amf_init_from_dxva2_device(AVCodecContext *avctx, AVDXVA2DeviceContext *hwctx)
-{
-    AmfContext *ctx = avctx->priv_data;
-    HANDLE device_handle;
-    IDirect3DDevice9 *device;
-    HRESULT hr;
-    AMF_RESULT res;
-    int ret;
-
-    hr = IDirect3DDeviceManager9_OpenDeviceHandle(hwctx->devmgr, &device_handle);
-    if (FAILED(hr)) {
-        av_log(avctx, AV_LOG_ERROR, "Failed to open device handle for Direct3D9 device: %lx.\n", (unsigned long)hr);
-        return AVERROR_EXTERNAL;
-    }
-
-    hr = IDirect3DDeviceManager9_LockDevice(hwctx->devmgr, device_handle, &device, FALSE);
-    if (SUCCEEDED(hr)) {
-        IDirect3DDeviceManager9_UnlockDevice(hwctx->devmgr, device_handle, FALSE);
-        ret = 0;
-    } else {
-        av_log(avctx, AV_LOG_ERROR, "Failed to lock device handle for Direct3D9 device: %lx.\n", (unsigned long)hr);
-        ret = AVERROR_EXTERNAL;
-    }
-
-    IDirect3DDeviceManager9_CloseDeviceHandle(hwctx->devmgr, device_handle);
-
-    if (ret < 0)
-        return ret;
-
-    res = ctx->context->pVtbl->InitDX9(ctx->context, device);
-
-    IDirect3DDevice9_Release(device);
-
-    if (res != AMF_OK) {
-        if (res == AMF_NOT_SUPPORTED)
-            av_log(avctx, AV_LOG_ERROR, "AMF via D3D9 is not supported on the given device.\n");
-        else
-            av_log(avctx, AV_LOG_ERROR, "AMF failed to initialise on given D3D9 device: %d.\n", res);
-        return AVERROR(ENODEV);
-    }
-
-    return 0;
-}
-#endif
-
-static int amf_init_context(AVCodecContext *avctx)
-{
-    AmfContext *ctx = avctx->priv_data;
-    AMF_RESULT  res;
-    av_unused int ret;
-
     ctx->hwsurfaces_in_queue = 0;
     ctx->hwsurfaces_in_queue_max = 16;
 
-    // configure AMF logger
-    // the return of these functions indicates old state and do not affect behaviour
-    ctx->trace->pVtbl->EnableWriter(ctx->trace, AMF_TRACE_WRITER_DEBUG_OUTPUT, ctx->log_to_dbg != 0 );
-    if (ctx->log_to_dbg)
-        ctx->trace->pVtbl->SetWriterLevel(ctx->trace, AMF_TRACE_WRITER_DEBUG_OUTPUT, AMF_TRACE_TRACE);
-    ctx->trace->pVtbl->EnableWriter(ctx->trace, AMF_TRACE_WRITER_CONSOLE, 0);
-    ctx->trace->pVtbl->SetGlobalLevel(ctx->trace, AMF_TRACE_TRACE);
-
-    // connect AMF logger to av_log
-    ctx->tracer.vtbl = &tracer_vtbl;
-    ctx->tracer.avctx = avctx;
-    ctx->trace->pVtbl->RegisterWriter(ctx->trace, FFMPEG_AMF_WRITER_ID,(AMFTraceWriter*)&ctx->tracer, 1);
-    ctx->trace->pVtbl->SetWriterLevel(ctx->trace, FFMPEG_AMF_WRITER_ID, AMF_TRACE_TRACE);
-
-    res = ctx->factory->pVtbl->CreateContext(ctx->factory, &ctx->context);
-    AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "CreateContext() failed with error %d\n", res);
-
     // If a device was passed to the encoder, try to initialise from that.
     if (avctx->hw_frames_ctx) {
         AVHWFramesContext *frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
@@ -246,26 +111,9 @@  static int amf_init_context(AVCodecContext *avctx)
             return AVERROR(EINVAL);
         }
 
-        switch (frames_ctx->device_ctx->type) {
-#if CONFIG_D3D11VA
-        case AV_HWDEVICE_TYPE_D3D11VA:
-            ret = amf_init_from_d3d11_device(avctx, frames_ctx->device_ctx->hwctx);
-            if (ret < 0)
-                return ret;
-            break;
-#endif
-#if CONFIG_DXVA2
-        case AV_HWDEVICE_TYPE_DXVA2:
-            ret = amf_init_from_dxva2_device(avctx, frames_ctx->device_ctx->hwctx);
-            if (ret < 0)
-                return ret;
-            break;
-#endif
-        default:
-            av_log(avctx, AV_LOG_ERROR, "AMF initialisation from a %s frames context is not supported.\n",
-                   av_hwdevice_get_type_name(frames_ctx->device_ctx->type));
-            return AVERROR(ENOSYS);
-        }
+        ret = av_hwdevice_ctx_create_derived(&ctx->amf_device_ctx, AV_HWDEVICE_TYPE_AMF, frames_ctx->device_ref, 0);
+        if (ret < 0)
+            return ret;
 
         ctx->hw_frames_ctx = av_buffer_ref(avctx->hw_frames_ctx);
         if (!ctx->hw_frames_ctx)
@@ -275,46 +123,26 @@  static int amf_init_context(AVCodecContext *avctx)
             ctx->hwsurfaces_in_queue_max = frames_ctx->initial_pool_size - 1;
 
     } else if (avctx->hw_device_ctx) {
-        AVHWDeviceContext *device_ctx = (AVHWDeviceContext*)avctx->hw_device_ctx->data;
-
-        switch (device_ctx->type) {
-#if CONFIG_D3D11VA
-        case AV_HWDEVICE_TYPE_D3D11VA:
-            ret = amf_init_from_d3d11_device(avctx, device_ctx->hwctx);
-            if (ret < 0)
-                return ret;
-            break;
-#endif
-#if CONFIG_DXVA2
-        case AV_HWDEVICE_TYPE_DXVA2:
-            ret = amf_init_from_dxva2_device(avctx, device_ctx->hwctx);
-            if (ret < 0)
-                return ret;
-            break;
-#endif
-        default:
-            av_log(avctx, AV_LOG_ERROR, "AMF initialisation from a %s device is not supported.\n",
-                   av_hwdevice_get_type_name(device_ctx->type));
-            return AVERROR(ENOSYS);
-        }
+        ret = av_hwdevice_ctx_create_derived(&ctx->amf_device_ctx, AV_HWDEVICE_TYPE_AMF, avctx->hw_device_ctx, 0);
+        if (ret < 0)
+            return ret;
 
         ctx->hw_device_ctx = av_buffer_ref(avctx->hw_device_ctx);
         if (!ctx->hw_device_ctx)
             return AVERROR(ENOMEM);
 
     } else {
-        res = ctx->context->pVtbl->InitDX11(ctx->context, NULL, AMF_DX11_1);
-        if (res == AMF_OK) {
-            av_log(avctx, AV_LOG_VERBOSE, "AMF initialisation succeeded via D3D11.\n");
-        } else {
-            res = ctx->context->pVtbl->InitDX9(ctx->context, NULL);
-            if (res == AMF_OK) {
-                av_log(avctx, AV_LOG_VERBOSE, "AMF initialisation succeeded via D3D9.\n");
-            } else {
-                av_log(avctx, AV_LOG_ERROR, "AMF initialisation failed via D3D9: error %d.\n", res);
-                return AVERROR(ENOSYS);
-            }
-        }
+        ret = av_hwdevice_ctx_create(&ctx->amf_device_ctx, AV_HWDEVICE_TYPE_AMF, NULL, NULL, 0);
+        if (ret < 0)
+            return ret;
+    }
+
+    if(ctx->amf_device_ctx)
+    {
+        AVHWDeviceContext *avhwctx =  (AVHWDeviceContext*)ctx->amf_device_ctx->data;
+        AVAMFDeviceContext *amf_ctx = avhwctx->hwctx;
+        ctx->context = amf_ctx->context;
+        ctx->factory = amf_ctx->factory;
     }
     return 0;
 }
@@ -368,29 +196,17 @@  int av_cold ff_amf_encode_close(AVCodecContext *avctx)
         ctx->encoder = NULL;
     }
 
-    if (ctx->context) {
-        ctx->context->pVtbl->Terminate(ctx->context);
-        ctx->context->pVtbl->Release(ctx->context);
-        ctx->context = NULL;
-    }
     av_buffer_unref(&ctx->hw_device_ctx);
     av_buffer_unref(&ctx->hw_frames_ctx);
 
-    if (ctx->trace) {
-        ctx->trace->pVtbl->UnregisterWriter(ctx->trace, FFMPEG_AMF_WRITER_ID);
-    }
-    if (ctx->library) {
-        dlclose(ctx->library);
-        ctx->library = NULL;
-    }
-    ctx->trace = NULL;
-    ctx->debug = NULL;
     ctx->factory = NULL;
-    ctx->version = 0;
+    ctx->context = NULL;
     ctx->delayed_drain = 0;
     av_frame_free(&ctx->delayed_frame);
     av_fifo_freep(&ctx->timestamp_list);
 
+    av_buffer_unref(&ctx->amf_device_ctx);
+
     return 0;
 }
 
@@ -494,11 +310,9 @@  int ff_amf_encode_init(AVCodecContext *avctx)
 {
     int ret;
 
-    if ((ret = amf_load_library(avctx)) == 0) {
-        if ((ret = amf_init_context(avctx)) == 0) {
-            if ((ret = amf_init_encoder(avctx)) == 0) {
-                return 0;
-            }
+    if ((ret = amf_init_context(avctx)) == 0) {
+        if ((ret = amf_init_encoder(avctx)) == 0) {
+            return 0;
         }
     }
     ff_amf_encode_close(avctx);
diff --git a/libavcodec/amfenc.h b/libavcodec/amfenc.h
index b1361842bd..9ce577fa8f 100644
--- a/libavcodec/amfenc.h
+++ b/libavcodec/amfenc.h
@@ -19,41 +19,26 @@ 
 #ifndef AVCODEC_AMFENC_H
 #define AVCODEC_AMFENC_H
 
-#include <AMF/core/Factory.h>
-
 #include <AMF/components/VideoEncoderVCE.h>
 #include <AMF/components/VideoEncoderHEVC.h>
 
 #include "libavutil/fifo.h"
+#include "libavutil/hwcontext_amf.h"
 
 #include "avcodec.h"
 
 
-/**
-* AMF trace writer callback class
-* Used to capture all AMF logging
-*/
-
-typedef struct AmfTraceWriter {
-    AMFTraceWriterVtbl *vtbl;
-    AVCodecContext     *avctx;
-} AmfTraceWriter;
-
 /**
 * AMF encoder context
 */
 
 typedef struct AmfContext {
     AVClass            *avclass;
-    // access to AMF runtime
-    amf_handle          library; ///< handle to DLL library
-    AMFFactory         *factory; ///< pointer to AMF factory
-    AMFDebug           *debug;   ///< pointer to AMF debug interface
-    AMFTrace           *trace;   ///< pointer to AMF trace interface
-
-    amf_uint64          version; ///< version of AMF runtime
-    AmfTraceWriter      tracer;  ///< AMF writer registered with AMF
-    AMFContext         *context; ///< AMF context
+
+    AMFContext         *context;
+    AMFFactory         *factory;
+    AVBufferRef        *amf_device_ctx;
+
     //encoder
     AMFComponent       *encoder; ///< AMF encoder object
     amf_bool            eof;     ///< flag indicating EOF happened
diff --git a/libavutil/Makefile b/libavutil/Makefile
index a63ba523c9..34b858c606 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -168,6 +168,7 @@  OBJS-$(CONFIG_VAAPI)                    += hwcontext_vaapi.o
 OBJS-$(CONFIG_VIDEOTOOLBOX)             += hwcontext_videotoolbox.o
 OBJS-$(CONFIG_VDPAU)                    += hwcontext_vdpau.o
 OBJS-$(CONFIG_MEDIACODEC)               += hwcontext_mediacodec.o
+OBJS-$(CONFIG_AMF)                      += hwcontext_amf.o
 
 OBJS += $(COMPAT_OBJS:%=../compat/%)
 
@@ -183,6 +184,7 @@  SKIPHEADERS-$(CONFIG_OPENCL)           += hwcontext_opencl.h
 SKIPHEADERS-$(CONFIG_VAAPI)            += hwcontext_vaapi.h
 SKIPHEADERS-$(CONFIG_VIDEOTOOLBOX)     += hwcontext_videotoolbox.h
 SKIPHEADERS-$(CONFIG_VDPAU)            += hwcontext_vdpau.h
+SKIPHEADERS-$(CONFIG_AMF)              += hwcontext_amf.h
 
 TESTPROGS = adler32                                                     \
             aes                                                         \
diff --git a/libavutil/hwcontext.c b/libavutil/hwcontext.c
index 70c556ecac..decf2d3566 100644
--- a/libavutil/hwcontext.c
+++ b/libavutil/hwcontext.c
@@ -58,6 +58,9 @@  static const HWContextType * const hw_table[] = {
 #endif
 #if CONFIG_MEDIACODEC
     &ff_hwcontext_type_mediacodec,
+#endif
+#if CONFIG_AMF
+    &ff_hwcontext_type_amf,
 #endif
     NULL,
 };
@@ -73,6 +76,7 @@  static const char *const hw_type_names[] = {
     [AV_HWDEVICE_TYPE_VDPAU]  = "vdpau",
     [AV_HWDEVICE_TYPE_VIDEOTOOLBOX] = "videotoolbox",
     [AV_HWDEVICE_TYPE_MEDIACODEC] = "mediacodec",
+    [AV_HWDEVICE_TYPE_AMF] = "amf",
 };
 
 enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
diff --git a/libavutil/hwcontext.h b/libavutil/hwcontext.h
index f5a4b62387..b18591205a 100644
--- a/libavutil/hwcontext.h
+++ b/libavutil/hwcontext.h
@@ -36,6 +36,7 @@  enum AVHWDeviceType {
     AV_HWDEVICE_TYPE_DRM,
     AV_HWDEVICE_TYPE_OPENCL,
     AV_HWDEVICE_TYPE_MEDIACODEC,
+    AV_HWDEVICE_TYPE_AMF,
 };
 
 typedef struct AVHWDeviceInternal AVHWDeviceInternal;
diff --git a/libavutil/hwcontext_amf.c b/libavutil/hwcontext_amf.c
new file mode 100644
index 0000000000..2c32f0e224
--- /dev/null
+++ b/libavutil/hwcontext_amf.c
@@ -0,0 +1,329 @@ 
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <string.h>
+
+#include "config.h"
+
+#include "avassert.h"
+#include "avstring.h"
+#include "common.h"
+#include "hwcontext.h"
+#include "hwcontext_internal.h"
+#include "hwcontext_amf.h"
+
+#if CONFIG_D3D11VA
+#include "libavutil/hwcontext_d3d11va.h"
+#endif
+
+#if CONFIG_DXVA2
+#define COBJMACROS
+#include "libavutil/hwcontext_dxva2.h"
+#endif
+
+#ifdef _WIN32
+#include "compat/w32dlfcn.h"
+#else
+#include <dlfcn.h>
+#endif
+
+/**
+* Error handling helper
+*/
+#define AMFAV_RETURN_IF_FALSE(avctx, exp, ret_value, /*message,*/ ...) \
+    if (!(exp)) { \
+        av_log(avctx, AV_LOG_ERROR, __VA_ARGS__); \
+        return ret_value; \
+    }
+
+typedef struct AmfTraceWriter {
+    AMFTraceWriterVtbl  *vtbl;
+    void                *avcl;
+} AmfTraceWriter;
+
+static void AMF_CDECL_CALL AMFTraceWriter_Write(AMFTraceWriter *pThis,
+    const wchar_t *scope, const wchar_t *message)
+{
+    AmfTraceWriter *tracer = (AmfTraceWriter*)pThis;
+    av_log(tracer->avcl, AV_LOG_DEBUG, "%ls: %ls", scope, message);
+}
+
+static void AMF_CDECL_CALL AMFTraceWriter_Flush(AMFTraceWriter *pThis)
+{
+}
+
+static AMFTraceWriterVtbl tracer_vtbl =
+{
+    .Write = AMFTraceWriter_Write,
+    .Flush = AMFTraceWriter_Flush,
+};
+
+#define AMFAV_WRITER_ID L"avlog"
+
+static const AVClass amflib_class = {
+    .class_name = "amf",
+    .item_name = av_default_item_name,
+    .version = LIBAVUTIL_VERSION_INT,
+};
+
+typedef struct AMFLibrary {
+    const AVClass      *avclass;
+    amf_handle          library;
+    AMFFactory         *factory;
+    AMFDebug           *debug;
+    AMFTrace           *trace;
+
+    amf_uint64          version;
+    AmfTraceWriter      tracer;
+
+} AMFLibrary;
+
+static void amf_library_ctx_free(void *opaque, uint8_t *data)
+{
+    AMFLibrary *ctx = (AMFLibrary*)data;
+
+    if (ctx->trace) {
+        ctx->trace->pVtbl->UnregisterWriter(ctx->trace, AMFAV_WRITER_ID);
+    }
+    if (ctx->library) {
+        dlclose(ctx->library);
+    }
+
+    av_freep(&ctx);
+}
+
+static AVBufferRef *amf_library_ctx_alloc(void)
+{
+    AVBufferRef *buf;
+    AMFLibrary  *ctx;
+
+    ctx = av_mallocz(sizeof(*ctx));
+    if (!ctx)
+        return NULL;
+
+    buf = av_buffer_create((uint8_t*)ctx, sizeof(*ctx), amf_library_ctx_free, NULL, AV_BUFFER_FLAG_READONLY);
+    return buf;
+}
+
+static int amf_init_library(AMFLibrary *ctx)
+{
+    AMFInit_Fn              init_fun = NULL;
+    AMFQueryVersion_Fn      version_fun = NULL;
+    AMF_RESULT              res = AMF_OK;
+
+    ctx->avclass = &amflib_class;
+    ctx->library = dlopen(AMF_DLL_NAMEA, RTLD_NOW | RTLD_LOCAL);
+    AMFAV_RETURN_IF_FALSE(ctx, ctx->library != NULL, AVERROR_UNKNOWN, "DLL %s failed to open\n", AMF_DLL_NAMEA);
+
+    init_fun = (AMFInit_Fn)dlsym(ctx->library, AMF_INIT_FUNCTION_NAME);
+    AMFAV_RETURN_IF_FALSE(ctx, init_fun != NULL, AVERROR_UNKNOWN, "DLL %s failed to find function %s\n", AMF_DLL_NAMEA, AMF_INIT_FUNCTION_NAME);
+
+    version_fun = (AMFQueryVersion_Fn)dlsym(ctx->library, AMF_QUERY_VERSION_FUNCTION_NAME);
+    AMFAV_RETURN_IF_FALSE(ctx, version_fun != NULL, AVERROR_UNKNOWN, "DLL %s failed to find function %s\n", AMF_DLL_NAMEA, AMF_QUERY_VERSION_FUNCTION_NAME);
+
+    res = version_fun(&ctx->version);
+    AMFAV_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_QUERY_VERSION_FUNCTION_NAME, res);
+    res = init_fun(AMF_FULL_VERSION, &ctx->factory);
+    AMFAV_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_INIT_FUNCTION_NAME, res);
+    res = ctx->factory->pVtbl->GetTrace(ctx->factory, &ctx->trace);
+    AMFAV_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "GetTrace() failed with error %d\n", res);
+    res = ctx->factory->pVtbl->GetDebug(ctx->factory, &ctx->debug);
+    AMFAV_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "GetDebug() failed with error %d\n", res);
+
+    ctx->trace->pVtbl->EnableWriter(ctx->trace, AMF_TRACE_WRITER_CONSOLE, 0);
+    ctx->trace->pVtbl->SetGlobalLevel(ctx->trace, AMF_TRACE_TRACE);
+
+    // connect AMF logger to av_log
+    ctx->tracer.vtbl = &tracer_vtbl;
+    ctx->tracer.avcl = ctx;
+    ctx->trace->pVtbl->RegisterWriter(ctx->trace, AMFAV_WRITER_ID, (AMFTraceWriter*)&ctx->tracer, 1);
+    ctx->trace->pVtbl->SetWriterLevel(ctx->trace, AMFAV_WRITER_ID, AMF_TRACE_TRACE);
+    return 0;
+}
+
+static AVBufferRef *amf_library_ctx = NULL;
+static AVBufferRef *aquire_amf_library_ctx(void)
+{
+    AVBufferRef *ret = NULL;
+    if (amf_library_ctx == NULL)
+    {
+        ret = amf_library_ctx_alloc();
+        if(amf_init_library((AMFLibrary *)ret->data) < 0)
+        {
+            av_buffer_unref(&amf_library_ctx);
+            ret = NULL;
+        } else {
+            amf_library_ctx = ret;
+        }
+    } else {
+        ret = av_buffer_ref(amf_library_ctx);
+    }
+    return ret;
+}
+
+typedef struct AVAMFDeviceContextPrivate {
+    AMFLibrary *lib;
+    AVBufferRef *lib_ref;
+} AVAMFDeviceContextPrivate;
+
+static int amf_init_device_ctx_object(AVHWDeviceContext *ctx)
+{
+    AVAMFDeviceContext *hwctx = ctx->hwctx;
+    AVAMFDeviceContextPrivate *priv = ctx->internal->priv;
+    AMF_RESULT res;
+
+    priv->lib_ref = aquire_amf_library_ctx();
+    priv->lib = (AMFLibrary*)priv->lib_ref->data;
+
+    res = priv->lib->factory->pVtbl->CreateContext(priv->lib->factory, &hwctx->context);
+    hwctx->factory = priv->lib->factory;
+    AMFAV_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "CreateContext() failed with error %d\n", res);
+    return 0;
+}
+
+static int amf_device_create(AVHWDeviceContext *ctx, const char *device,
+                                AVDictionary *opts, int flags)
+{
+    AVAMFDeviceContext *amf_ctx = ctx->hwctx;
+    AMF_RESULT res;
+    int err;
+
+    err = amf_init_device_ctx_object(ctx);
+    if(err < 0)
+        return err;
+
+    res = amf_ctx->context->pVtbl->InitDX11(amf_ctx->context, NULL, AMF_DX11_1);
+    if (res == AMF_OK) {
+        av_log(ctx, AV_LOG_VERBOSE, "AMF initialisation succeeded via D3D11.\n");
+    } else {
+        res = amf_ctx->context->pVtbl->InitDX9(amf_ctx->context, NULL);
+        if (res == AMF_OK) {
+            av_log(ctx, AV_LOG_VERBOSE, "AMF initialisation succeeded via D3D9.\n");
+        } else {
+            av_log(ctx, AV_LOG_ERROR, "AMF initialisation failed via D3D9: error %d.\n", res);
+            return AVERROR(ENOSYS);
+        }
+    }
+    return 0;
+}
+
+static int amf_device_derive(AVHWDeviceContext *dst_ctx,
+                                AVHWDeviceContext *src_ctx,
+                                int flags)
+{
+    AVAMFDeviceContext *amf_ctx = dst_ctx->hwctx;
+    AMF_RESULT res;
+    int err;
+
+    err = amf_init_device_ctx_object(dst_ctx);
+    if(err < 0)
+        return err;
+
+    switch (src_ctx->type) {
+
+#if CONFIG_D3D11VA
+    case AV_HWDEVICE_TYPE_DXVA2:
+        {
+            AVDXVA2DeviceContext *dxva2_ctx = src_ctx->hwctx;
+            HANDLE device_handle;
+            IDirect3DDevice9 *device;
+            HRESULT hr;
+            AMF_RESULT res;
+            int ret;
+
+            hr = IDirect3DDeviceManager9_OpenDeviceHandle(dxva2_ctx->devmgr, &device_handle);
+            if (FAILED(hr)) {
+                av_log(dst_ctx, AV_LOG_ERROR, "Failed to open device handle for Direct3D9 device: %lx.\n", (unsigned long)hr);
+                return AVERROR_EXTERNAL;
+            }
+
+            hr = IDirect3DDeviceManager9_LockDevice(dxva2_ctx->devmgr, device_handle, &device, FALSE);
+            if (SUCCEEDED(hr)) {
+                IDirect3DDeviceManager9_UnlockDevice(dxva2_ctx->devmgr, device_handle, FALSE);
+                ret = 0;
+            } else {
+                av_log(dst_ctx, AV_LOG_ERROR, "Failed to lock device handle for Direct3D9 device: %lx.\n", (unsigned long)hr);
+                ret = AVERROR_EXTERNAL;
+            }
+
+            IDirect3DDeviceManager9_CloseDeviceHandle(dxva2_ctx->devmgr, device_handle);
+
+            if (ret < 0)
+                return ret;
+
+            res = amf_ctx->context->pVtbl->InitDX9(amf_ctx->context, device);
+
+            IDirect3DDevice9_Release(device);
+
+            if (res != AMF_OK) {
+                if (res == AMF_NOT_SUPPORTED)
+                    av_log(dst_ctx, AV_LOG_ERROR, "AMF via D3D9 is not supported on the given device.\n");
+                else
+                    av_log(dst_ctx, AV_LOG_ERROR, "AMF failed to initialise on given D3D9 device: %d.\n", res);
+                return AVERROR(ENODEV);
+            }
+        }
+        break;
+#endif
+
+#if CONFIG_D3D11VA
+    case AV_HWDEVICE_TYPE_D3D11VA:
+        {
+            AVD3D11VADeviceContext *d3d11_ctx = src_ctx->hwctx;
+            res = amf_ctx->context->pVtbl->InitDX11(amf_ctx->context, d3d11_ctx->device, AMF_DX11_1);
+            if (res != AMF_OK) {
+                if (res == AMF_NOT_SUPPORTED)
+                    av_log(dst_ctx, AV_LOG_ERROR, "AMF via D3D11 is not supported on the given device.\n");
+                else
+                    av_log(dst_ctx, AV_LOG_ERROR, "AMF failed to initialise on the given D3D11 device: %d.\n", res);
+                return AVERROR(ENODEV);
+            }
+        }
+        break;
+#endif
+    default:
+        av_log(dst_ctx, AV_LOG_ERROR, "AMF initialisation from a %s device is not supported.\n",
+                av_hwdevice_get_type_name(src_ctx->type));
+        return AVERROR(ENOSYS);
+    }
+    return 0;
+}
+
+static void amf_device_uninit(AVHWDeviceContext *ctx)
+{
+    AVAMFDeviceContext *amf_ctx = ctx->hwctx;
+    AVAMFDeviceContextPrivate *priv = ctx->internal->priv;
+    if (amf_ctx->context) {
+        amf_ctx->context->pVtbl->Terminate(amf_ctx->context);
+        amf_ctx->context->pVtbl->Release(amf_ctx->context);
+        amf_ctx->context = NULL;
+    }
+    av_buffer_unref(&priv->lib_ref);
+}
+
+const HWContextType ff_hwcontext_type_amf = {
+    .type                   = AV_HWDEVICE_TYPE_AMF,
+    .name                   = "AMF",
+
+    .device_hwctx_size      = sizeof(AVAMFDeviceContext),
+    .device_priv_size       = sizeof(AVAMFDeviceContextPrivate),
+
+    .device_create          = &amf_device_create,
+    .device_derive          = &amf_device_derive,
+    .device_uninit          = &amf_device_uninit,
+};
diff --git a/libavutil/hwcontext_amf.h b/libavutil/hwcontext_amf.h
new file mode 100644
index 0000000000..1b19fd2ce8
--- /dev/null
+++ b/libavutil/hwcontext_amf.h
@@ -0,0 +1,43 @@ 
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+
+#ifndef AVUTIL_HWCONTEXT_AMF_H
+#define AVUTIL_HWCONTEXT_AMF_H
+
+/**
+ * @file
+ * API-specific header for AV_HWDEVICE_TYPE_AMF.
+ *
+ */
+
+#include "frame.h"
+#include "AMF/core/Context.h"
+#include "AMF/core/Factory.h"
+
+
+/**
+ * This struct is allocated as AVHWDeviceContext.hwctx
+ */
+typedef struct AVAMFDeviceContext {
+    AMFContext *context;
+    AMFFactory *factory;
+} AVAMFDeviceContext;
+
+
+#endif /* AVUTIL_HWCONTEXT_AMF_H */
diff --git a/libavutil/hwcontext_internal.h b/libavutil/hwcontext_internal.h
index 332062ddaa..179797a936 100644
--- a/libavutil/hwcontext_internal.h
+++ b/libavutil/hwcontext_internal.h
@@ -167,5 +167,6 @@  extern const HWContextType ff_hwcontext_type_vaapi;
 extern const HWContextType ff_hwcontext_type_vdpau;
 extern const HWContextType ff_hwcontext_type_videotoolbox;
 extern const HWContextType ff_hwcontext_type_mediacodec;
+extern const HWContextType ff_hwcontext_type_amf;
 
 #endif /* AVUTIL_HWCONTEXT_INTERNAL_H */