hwcontext_amf.c

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/*
 * 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 "buffer.h"
#include "common.h"
#include "hwcontext.h"
#include "hwcontext_amf.h"
#include "hwcontext_internal.h"
#include "hwcontext_amf_internal.h"
#if CONFIG_VULKAN
#include "hwcontext_vulkan.h"
#endif
#if CONFIG_D3D11VA
#include "libavutil/hwcontext_d3d11va.h"
#endif
#if CONFIG_DXVA2
#define COBJMACROS
#include "libavutil/hwcontext_dxva2.h"
#endif
#include "mem.h"
#include "pixdesc.h"
#include "pixfmt.h"
#include "imgutils.h"
#include "libavutil/avassert.h"
#include <AMF/core/Surface.h>
#include <AMF/core/Trace.h>
#ifdef _WIN32
#include "compat/w32dlfcn.h"
#else
#include <dlfcn.h>
#endif
#define FFMPEG_AMF_WRITER_ID L"ffmpeg_amf"
 
 
typedef struct AmfTraceWriter {
    AMFTraceWriterVtbl *vtblp;
    void               *avctx;
    AMFTraceWriterVtbl  vtbl;
} 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->avctx, AV_LOG_DEBUG, "%ls: %ls", scope, message); // \n is provided from AMF
}
 
static void AMF_CDECL_CALL AMFTraceWriter_Flush(AMFTraceWriter *pThis)
{
}
 
static AmfTraceWriter * amf_writer_alloc(void  *avctx)
{
    AmfTraceWriter * writer = av_mallocz(sizeof(AmfTraceWriter));
    if (!writer)
        return NULL;
 
    writer->vtblp = &writer->vtbl;
    writer->vtblp->Write = AMFTraceWriter_Write;
    writer->vtblp->Flush = AMFTraceWriter_Flush;
    writer->avctx = avctx;
 
    return writer;
}
 
static void amf_writer_free(void  *opaque)
{
    AmfTraceWriter *writer = (AmfTraceWriter *)opaque;
    av_freep(&writer);
}
 
/**
 * We still need AVHWFramesContext to utilize our hardware memory
 * otherwise, we will receive the error "HW format requires hw_frames_ctx to be non-NULL".
 * (libavfilter\buffersrc.c function query_formats)
*/
typedef struct {
    void *dummy;
} AMFFramesContext;
 
typedef struct AVAMFFormatMap {
    enum AVPixelFormat       av_format;
    enum AMF_SURFACE_FORMAT  amf_format;
} FormatMap;
 
const FormatMap format_map[] =
{
    { AV_PIX_FMT_NONE,          AMF_SURFACE_UNKNOWN },
    { AV_PIX_FMT_NV12,          AMF_SURFACE_NV12 },
    { AV_PIX_FMT_BGR0,          AMF_SURFACE_BGRA },
    { AV_PIX_FMT_RGB0,          AMF_SURFACE_RGBA },
    { AV_PIX_FMT_BGRA,          AMF_SURFACE_BGRA },
    { AV_PIX_FMT_ARGB,          AMF_SURFACE_ARGB },
    { AV_PIX_FMT_RGBA,          AMF_SURFACE_RGBA },
    { AV_PIX_FMT_GRAY8,         AMF_SURFACE_GRAY8 },
    { AV_PIX_FMT_YUV420P,       AMF_SURFACE_YUV420P },
    { AV_PIX_FMT_YUYV422,       AMF_SURFACE_YUY2 },
    { AV_PIX_FMT_P010,          AMF_SURFACE_P010 },
    { AV_PIX_FMT_X2BGR10,       AMF_SURFACE_R10G10B10A2 },
    { AV_PIX_FMT_RGBAF16,       AMF_SURFACE_RGBA_F16},
};
 
enum AMF_SURFACE_FORMAT av_av_to_amf_format(enum AVPixelFormat fmt)
{
    int i;
    for (i = 0; i < amf_countof(format_map); i++) {
        if (format_map[i].av_format == fmt) {
            return format_map[i].amf_format;
        }
    }
    return AMF_SURFACE_UNKNOWN;
}
 
enum AVPixelFormat av_amf_to_av_format(enum AMF_SURFACE_FORMAT fmt)
{
    int i;
    for (i = 0; i < amf_countof(format_map); i++) {
        if (format_map[i].amf_format == fmt) {
            return format_map[i].av_format;
        }
    }
    return AMF_SURFACE_UNKNOWN;
}
 
static const enum AVPixelFormat supported_formats[] = {
    AV_PIX_FMT_NV12,
    AV_PIX_FMT_YUV420P,
    AV_PIX_FMT_BGRA,
    AV_PIX_FMT_RGBA,
    AV_PIX_FMT_P010,
#if CONFIG_D3D11VA
    AV_PIX_FMT_D3D11,
#endif
#if CONFIG_DXVA2
    AV_PIX_FMT_DXVA2_VLD,
#endif
};
 
static const enum AVPixelFormat supported_transfer_formats[] = {
    AV_PIX_FMT_NV12,
    AV_PIX_FMT_YUV420P,
    AV_PIX_FMT_BGRA,
    AV_PIX_FMT_RGBA,
    AV_PIX_FMT_P010,
    AV_PIX_FMT_NONE,
};
 
static int amf_frames_get_constraints(AVHWDeviceContext *ctx,
                                       const void *hwconfig,
                                       AVHWFramesConstraints *constraints)
{
    int i;
 
    constraints->valid_sw_formats = av_malloc_array(FF_ARRAY_ELEMS(supported_formats) + 1,
                                                    sizeof(*constraints->valid_sw_formats));
    if (!constraints->valid_sw_formats)
        return AVERROR(ENOMEM);
 
    for (i = 0; i < FF_ARRAY_ELEMS(supported_formats); i++)
        constraints->valid_sw_formats[i] = supported_formats[i];
    constraints->valid_sw_formats[FF_ARRAY_ELEMS(supported_formats)] = AV_PIX_FMT_NONE;
 
    constraints->valid_hw_formats = av_malloc_array(2, sizeof(*constraints->valid_hw_formats));
    if (!constraints->valid_hw_formats)
        return AVERROR(ENOMEM);
 
    constraints->valid_hw_formats[0] = AV_PIX_FMT_AMF_SURFACE;
    constraints->valid_hw_formats[1] = AV_PIX_FMT_NONE;
 
    return 0;
}
 
static void amf_dummy_free(void *opaque, uint8_t *data)
{
 
}
 
static AVBufferRef *amf_pool_alloc(void *opaque, size_t size)
{
    AVHWFramesContext *hwfc = (AVHWFramesContext *)opaque;
    AVBufferRef *buf;
 
    buf = av_buffer_create(NULL, 0, amf_dummy_free, hwfc, AV_BUFFER_FLAG_READONLY);
    if (!buf) {
        av_log(hwfc, AV_LOG_ERROR, "Failed to create buffer for AMF context.\n");
        return NULL;
    }
    return buf;
}
 
static int amf_frames_init(AVHWFramesContext *ctx)
{
    int i;
 
    for (i = 0; i < FF_ARRAY_ELEMS(supported_formats); i++) {
        if (ctx->sw_format == supported_formats[i])
            break;
    }
    if (i == FF_ARRAY_ELEMS(supported_formats)) {
        av_log(ctx, AV_LOG_ERROR, "Pixel format '%s' is not supported\n",
               av_get_pix_fmt_name(ctx->sw_format));
        return AVERROR(ENOSYS);
    }
 
    ffhwframesctx(ctx)->pool_internal =
            av_buffer_pool_init2(sizeof(AMFSurface), ctx,
                                 &amf_pool_alloc, NULL);
 
    return 0;
}
 
 
static int amf_get_buffer(AVHWFramesContext *ctx, AVFrame *frame)
{
    frame->buf[0] = av_buffer_pool_get(ctx->pool);
    if (!frame->buf[0])
        return AVERROR(ENOMEM);
 
    frame->data[0] = frame->buf[0]->data;
    frame->format  = AV_PIX_FMT_AMF_SURFACE;
    frame->width   = ctx->width;
    frame->height  = ctx->height;
    return 0;
}
 
static int amf_transfer_get_formats(AVHWFramesContext *ctx,
                                     enum AVHWFrameTransferDirection dir,
                                     enum AVPixelFormat **formats)
{
    enum AVPixelFormat *fmts;
    int i;
 
    fmts = av_malloc_array(FF_ARRAY_ELEMS(supported_transfer_formats), sizeof(*fmts));
    if (!fmts)
        return AVERROR(ENOMEM);
    for (i = 0; i < FF_ARRAY_ELEMS(supported_transfer_formats); i++)
        fmts[i] = supported_transfer_formats[i];
 
    *formats = fmts;
 
    return 0;
}
 
static void amf_free_amfsurface(void *opaque, uint8_t *data)
{
    if(!!data){
        AMFSurface *surface = (AMFSurface*)(data);
        surface->pVtbl->Release(surface);
    }
}
 
static int amf_transfer_data_to(AVHWFramesContext *ctx, AVFrame *dst,
                                 const AVFrame *src)
{
    AMFSurface* surface = (AMFSurface*)dst->data[0];
    AMFPlane *plane;
    uint8_t  *dst_data[4];
    int       dst_linesize[4];
    int       planes;
    int       i;
    int       res;
    int w = FFMIN(dst->width,  src->width);
    int h = FFMIN(dst->height, src->height);
 
    if (!surface) {
        AVHWDeviceContext   *hwdev_ctx = ctx->device_ctx;
        AVAMFDeviceContext  *amf_device_ctx = (AVAMFDeviceContext *)hwdev_ctx->hwctx;
        AMF_SURFACE_FORMAT  format = av_av_to_amf_format(ctx->sw_format);
        res = amf_device_ctx->context->pVtbl->AllocSurface(amf_device_ctx->context, AMF_MEMORY_HOST, format, dst->width, dst->height, &surface);
        AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR(ENOMEM), "AllocSurface() failed  with error %d\n", res);
        dst->data[0] = (uint8_t *)surface;
        dst->buf[1] = av_buffer_create((uint8_t *)surface, sizeof(surface),
                                            amf_free_amfsurface,
                                            NULL,
                                            AV_BUFFER_FLAG_READONLY);
    AMF_RETURN_IF_FALSE(ctx, !!dst->buf[1], AVERROR(ENOMEM), "av_buffer_create for amf surface failed.");
    }
 
    planes = (int)surface->pVtbl->GetPlanesCount(surface);
    av_assert0(planes < FF_ARRAY_ELEMS(dst_data));
 
    for (i = 0; i < planes; i++) {
        plane = surface->pVtbl->GetPlaneAt(surface, i);
        dst_data[i] = plane->pVtbl->GetNative(plane);
        dst_linesize[i] = plane->pVtbl->GetHPitch(plane);
    }
    av_image_copy2(dst_data, dst_linesize,
                   src->data, src->linesize, src->format,
                   w, h);
 
    return 0;
}
 
static int amf_transfer_data_from(AVHWFramesContext *ctx, AVFrame *dst,
                                    const AVFrame *src)
{
    AMFSurface* surface = (AMFSurface*)src->data[0];
    AMFPlane *plane;
    uint8_t  *src_data[4];
    int       src_linesize[4];
    int       planes;
    int       i;
    int w = FFMIN(dst->width,  src->width);
    int h = FFMIN(dst->height, src->height);
    int ret;
 
    ret = surface->pVtbl->Convert(surface, AMF_MEMORY_HOST);
    AMF_RETURN_IF_FALSE(ctx, ret == AMF_OK, AVERROR_UNKNOWN, "Convert(amf::AMF_MEMORY_HOST) failed with error %d\n", AVERROR_UNKNOWN);
 
    planes = (int)surface->pVtbl->GetPlanesCount(surface);
    av_assert0(planes < FF_ARRAY_ELEMS(src_data));
 
    for (i = 0; i < planes; i++) {
        plane = surface->pVtbl->GetPlaneAt(surface, i);
        src_data[i] = plane->pVtbl->GetNative(plane);
        src_linesize[i] = plane->pVtbl->GetHPitch(plane);
    }
    av_image_copy2(dst->data, dst->linesize,
                   src_data, src_linesize, dst->format,
                   w, h);
    return 0;
}
 
 
 
static void amf_device_uninit(AVHWDeviceContext *device_ctx)
{
    AVAMFDeviceContext      *amf_ctx = device_ctx->hwctx;
    AMF_RESULT          res = AMF_NOT_INITIALIZED;
    AMFTrace           *trace;
 
    if (amf_ctx->context) {
        amf_ctx->context->pVtbl->Terminate(amf_ctx->context);
        amf_ctx->context->pVtbl->Release(amf_ctx->context);
        amf_ctx->context = NULL;
    }
 
    if (amf_ctx->factory)
        res = amf_ctx->factory->pVtbl->GetTrace(amf_ctx->factory, &trace);
 
    if (res == AMF_OK) {
        trace->pVtbl->UnregisterWriter(trace, FFMPEG_AMF_WRITER_ID);
    }
 
    if(amf_ctx->library) {
        dlclose(amf_ctx->library);
        amf_ctx->library = NULL;
    }
    if (amf_ctx->trace_writer) {
        amf_writer_free(amf_ctx->trace_writer);
    }
 
    amf_ctx->version = 0;
}
 
static int amf_device_init(AVHWDeviceContext *ctx)
{
    AVAMFDeviceContext *amf_ctx = ctx->hwctx;
    AMFContext1 *context1 = NULL;
    AMF_RESULT res;
 
#ifdef _WIN32
    res = amf_ctx->context->pVtbl->InitDX11(amf_ctx->context, NULL, AMF_DX11_1);
    if (res == AMF_OK || res == AMF_ALREADY_INITIALIZED) {
        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 {
#endif
            AMFGuid guid = IID_AMFContext1();
            res = amf_ctx->context->pVtbl->QueryInterface(amf_ctx->context, &guid, (void**)&context1);
            AMF_RETURN_IF_FALSE(ctx, res == AMF_OK, AVERROR_UNKNOWN, "CreateContext1() failed with error %d\n", res);
 
            res = context1->pVtbl->InitVulkan(context1, NULL);
            context1->pVtbl->Release(context1);
            if (res != AMF_OK && res != AMF_ALREADY_INITIALIZED) {
                if (res == AMF_NOT_SUPPORTED)
                    av_log(ctx, AV_LOG_ERROR, "AMF via Vulkan is not supported on the given device.\n");
                 else
                    av_log(ctx, AV_LOG_ERROR, "AMF failed to initialise on the given Vulkan device: %d.\n", res);
                 return AVERROR(ENOSYS);
            }
            av_log(ctx, AV_LOG_VERBOSE, "AMF initialisation succeeded via Vulkan.\n");
#ifdef _WIN32
        }
     }
#endif
     return 0;
}
 
static int amf_load_library(AVAMFDeviceContext* amf_ctx,  void* avcl)
{
    AMFInit_Fn         init_fun;
    AMFQueryVersion_Fn version_fun;
    AMF_RESULT         res;
 
    amf_ctx->library = dlopen(AMF_DLL_NAMEA, RTLD_NOW | RTLD_LOCAL);
    AMF_RETURN_IF_FALSE(avcl, amf_ctx->library != NULL,
        AVERROR_UNKNOWN, "DLL %s failed to open\n", AMF_DLL_NAMEA);
 
    init_fun = (AMFInit_Fn)dlsym(amf_ctx->library, AMF_INIT_FUNCTION_NAME);
    AMF_RETURN_IF_FALSE(avcl, 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(amf_ctx->library, AMF_QUERY_VERSION_FUNCTION_NAME);
    AMF_RETURN_IF_FALSE(avcl, version_fun != NULL, AVERROR_UNKNOWN, "DLL %s failed to find function %s\n", AMF_DLL_NAMEA, AMF_QUERY_VERSION_FUNCTION_NAME);
 
    res = version_fun(&amf_ctx->version);
    AMF_RETURN_IF_FALSE(avcl, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_QUERY_VERSION_FUNCTION_NAME, res);
    res = init_fun(AMF_FULL_VERSION, &amf_ctx->factory);
    AMF_RETURN_IF_FALSE(avcl, res == AMF_OK, AVERROR_UNKNOWN, "%s failed with error %d\n", AMF_INIT_FUNCTION_NAME, res);
    return 0;
}
 
static int amf_device_create(AVHWDeviceContext *device_ctx,
                              const char *device,
                              AVDictionary *opts, int flags)
{
    AVAMFDeviceContext        *ctx = device_ctx->hwctx;
    AMFTrace           *trace;
    int ret;
    if ((ret = amf_load_library(ctx, device_ctx)) == 0) {
        ret = ctx->factory->pVtbl->GetTrace(ctx->factory, &trace);
        if (ret == AMF_OK) {
            int level_ff = av_log_get_level();
            int level_amf = AMF_TRACE_TRACE;
            amf_bool enable_log = true;
            switch(level_ff)
            {
            case AV_LOG_QUIET:
                level_amf = AMF_TRACE_ERROR;
                enable_log = false;
                break;
            case AV_LOG_PANIC:
            case AV_LOG_FATAL:
            case AV_LOG_ERROR:
                level_amf = AMF_TRACE_ERROR;
                break;
            case AV_LOG_WARNING:
            case AV_LOG_INFO:
                level_amf = AMF_TRACE_WARNING;
                break;
            case AV_LOG_VERBOSE:
                level_amf = AMF_TRACE_INFO;
                break;
            case AV_LOG_DEBUG:
                level_amf = AMF_TRACE_DEBUG;
                break;
            case AV_LOG_TRACE:
                level_amf = AMF_TRACE_TRACE;
                break;
            }
            if(ctx->version == AMF_MAKE_FULL_VERSION(1, 4, 35, 0)){// get around a bug in trace in AMF runtime driver 24.20
                level_amf = AMF_TRACE_WARNING;
            }
 
            trace->pVtbl->EnableWriter(trace, AMF_TRACE_WRITER_CONSOLE, 0);
            trace->pVtbl->SetGlobalLevel(trace, level_amf);
 
            // connect AMF logger to av_log
            ctx->trace_writer = amf_writer_alloc(device_ctx);
            trace->pVtbl->RegisterWriter(trace, FFMPEG_AMF_WRITER_ID, (AMFTraceWriter*)ctx->trace_writer, 1);
            trace->pVtbl->SetWriterLevel(trace, FFMPEG_AMF_WRITER_ID, level_amf);
            trace->pVtbl->EnableWriter(trace, FFMPEG_AMF_WRITER_ID, enable_log);
            trace->pVtbl->SetWriterLevel(trace, AMF_TRACE_WRITER_DEBUG_OUTPUT, level_amf);
            trace->pVtbl->EnableWriter(trace, AMF_TRACE_WRITER_DEBUG_OUTPUT, enable_log);
        }
 
 
        ret = ctx->factory->pVtbl->CreateContext(ctx->factory, &ctx->context);
        if (ret == AMF_OK)
            return 0;
        av_log(device_ctx, AV_LOG_ERROR, "CreateContext() failed with error %d.\n", ret);
    }
    amf_device_uninit(device_ctx);
    return ret;
}
 
#if CONFIG_DXVA2
static int amf_init_from_dxva2_device(AVAMFDeviceContext * amf_ctx, AVDXVA2DeviceContext *hwctx)
{
    IDirect3DDevice9    *device;
    HANDLE              device_handle;
    HRESULT             hr;
    AMF_RESULT          res;
    int ret;
 
    hr = IDirect3DDeviceManager9_OpenDeviceHandle(hwctx->devmgr, &device_handle);
    if (FAILED(hr)) {
        av_log(hwctx, 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(hwctx, 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 = amf_ctx->context->pVtbl->InitDX9(amf_ctx->context, device);
 
    IDirect3DDevice9_Release(device);
 
    if (res != AMF_OK && res != AMF_ALREADY_INITIALIZED) {
        if (res == AMF_NOT_SUPPORTED)
            av_log(hwctx, AV_LOG_ERROR, "AMF via D3D9 is not supported on the given device.\n");
        else
            av_log(hwctx, AV_LOG_ERROR, "AMF failed to initialise on given D3D9 device: %d.\n", res);
        return AVERROR(ENODEV);
    }
    return 0;
}
#endif
 
#if CONFIG_D3D11VA
static int amf_init_from_d3d11_device(AVAMFDeviceContext* amf_ctx, AVD3D11VADeviceContext *hwctx)
{
    AMF_RESULT res;
    res = amf_ctx->context->pVtbl->InitDX11(amf_ctx->context, hwctx->device, AMF_DX11_1);
    if (res != AMF_OK && res != AMF_ALREADY_INITIALIZED) {
        if (res == AMF_NOT_SUPPORTED)
            av_log(hwctx, AV_LOG_ERROR, "AMF via D3D11 is not supported on the given device.\n");
        else
            av_log(hwctx, AV_LOG_ERROR, "AMF failed to initialise on the given D3D11 device: %d.\n", res);
        return AVERROR(ENODEV);
    }
    return 0;
}
#endif
 
static int amf_device_derive(AVHWDeviceContext *device_ctx,
                              AVHWDeviceContext *child_device_ctx, AVDictionary *opts,
                              int flags)
{
#if CONFIG_DXVA2 || CONFIG_D3D11VA
    AVAMFDeviceContext        *amf_ctx = device_ctx->hwctx;
#endif
    int ret;
 
    ret = amf_device_create(device_ctx, "", opts, flags);
    if(ret < 0)
        return ret;
 
    switch (child_device_ctx->type) {
 
#if CONFIG_DXVA2
    case AV_HWDEVICE_TYPE_DXVA2: {
            AVDXVA2DeviceContext *child_device_hwctx = child_device_ctx->hwctx;
            return amf_init_from_dxva2_device(amf_ctx, child_device_hwctx);
        }
        break;
#endif
 
#if CONFIG_D3D11VA
    case AV_HWDEVICE_TYPE_D3D11VA: {
            AVD3D11VADeviceContext *child_device_hwctx = child_device_ctx->hwctx;
            return amf_init_from_d3d11_device(amf_ctx, child_device_hwctx);
        }
        break;
#endif
    default: {
            av_log(child_device_ctx, AV_LOG_ERROR, "AMF initialisation from a %s device is not supported.\n",
                av_hwdevice_get_type_name(child_device_ctx->type));
            return AVERROR(ENOSYS);
        }
    }
    return 0;
}
 
const HWContextType ff_hwcontext_type_amf = {
    .type                 = AV_HWDEVICE_TYPE_AMF,
    .name                 = "AMF",
 
    .device_hwctx_size    = sizeof(AVAMFDeviceContext),
    .frames_hwctx_size    = sizeof(AMFFramesContext),
 
    .device_create        = amf_device_create,
    .device_derive        = amf_device_derive,
    .device_init          = amf_device_init,
    .device_uninit        = amf_device_uninit,
    .frames_get_constraints = amf_frames_get_constraints,
    .frames_init          = amf_frames_init,
    .frames_get_buffer    = amf_get_buffer,
    .transfer_get_formats = amf_transfer_get_formats,
    .transfer_data_to     = amf_transfer_data_to,
    .transfer_data_from   = amf_transfer_data_from,
 
    .pix_fmts             = (const enum AVPixelFormat[]){ AV_PIX_FMT_AMF_SURFACE, AV_PIX_FMT_NONE },
};