ffmpeg实现dxva2硬件加速

/*
 * 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 FFMPEG_DXVA2_H
#define FFMPEG_DXVA2_H

//#include "windows.h"

extern "C"{
#include "libavcodec/avcodec.h"
#include "libavutil/pixfmt.h"
#include "libavutil/rational.h"
}

enum HWAccelID {
    HWACCEL_NONE = 0,
    HWACCEL_AUTO,
    HWACCEL_VDPAU,
    HWACCEL_DXVA2,
    HWACCEL_VDA,
    HWACCEL_VIDEOTOOLBOX,
    HWACCEL_QSV,
};

typedef struct AVStream AVStream;
typedef struct AVCodecContext AVCodecContext;
typedef struct AVCodec AVCodec;
typedef struct AVFrame AVFrame;
typedef struct AVDictionary AVDictionary;

typedef struct InputStream {
    int file_index;
    AVStream *st;
    int discard;             /* true if stream data should be discarded */
    int user_set_discard;
    int decoding_needed;     /* non zero if the packets must be decoded in 'raw_fifo', see DECODING_FOR_* */
#define DECODING_FOR_OST    1
#define DECODING_FOR_FILTER 2

    AVCodecContext *dec_ctx;
    AVCodec *dec;
    AVFrame *decoded_frame;
    AVFrame *filter_frame; /* a ref of decoded_frame, to be sent to filters */

    int64_t       start;     /* time when read started */
    /* predicted dts of the next packet read for this stream or (when there are
        * several frames in a packet) of the next frame in current packet (in AV_TIME_BASE units) */
    int64_t       next_dts;
    int64_t       dts;       ///< dts of the last packet read for this stream (in AV_TIME_BASE units)

    int64_t       next_pts;  ///< synthetic pts for the next decode frame (in AV_TIME_BASE units)
    int64_t       pts;       ///< current pts of the decoded frame  (in AV_TIME_BASE units)
    int           wrap_correction_done;

    int64_t filter_in_rescale_delta_last;

    int64_t min_pts; /* pts with the smallest value in a current stream */
    int64_t max_pts; /* pts with the higher value in a current stream */
    int64_t nb_samples; /* number of samples in the last decoded audio frame before looping */

    double ts_scale;
    int saw_first_ts;
    int showed_multi_packet_warning;
    AVDictionary *decoder_opts;
    AVRational framerate;               /* framerate forced with -r */
    int top_field_first;
    int guess_layout_max;

    int autorotate;
    int resample_height;
    int resample_width;
    int resample_pix_fmt;

    int      resample_sample_fmt;
    int      resample_sample_rate;
    int      resample_channels;
    uint64_t resample_channel_layout;

    int fix_sub_duration;
    struct { /* previous decoded subtitle and related variables */
        int got_output;
        int ret;
        AVSubtitle subtitle;
    } prev_sub;

    struct sub2video {
        int64_t last_pts;
        int64_t end_pts;
        AVFrame *frame;
        int w, h;
    } sub2video;

    int dr1;

    /* decoded data from this stream goes into all those filters
        * currently video and audio only */
    //InputFilter **filters;
    //int        nb_filters;

    //int reinit_filters;

    /* hwaccel options */
    enum HWAccelID hwaccel_id;
    char  *hwaccel_device;

    /* hwaccel context */
    enum HWAccelID active_hwaccel_id;
    void  *hwaccel_ctx;
    void(*hwaccel_uninit)(AVCodecContext *s);
    int(*hwaccel_get_buffer)(AVCodecContext *s, AVFrame *frame, int flags);
    int(*hwaccel_retrieve_data)(AVCodecContext *s, AVFrame *frame);
    enum AVPixelFormat hwaccel_pix_fmt;
    enum AVPixelFormat hwaccel_retrieved_pix_fmt;

    /* stats */
    // combined size of all the packets read
    uint64_t data_size;
    /* number of packets successfully read for this stream */
    uint64_t nb_packets;
    // number of frames/samples retrieved from the decoder
    uint64_t frames_decoded;
    uint64_t samples_decoded;
} InputStream;


int dxva2_init(AVCodecContext *s, HWND hwnd);
int dxva2_retrieve_data_call(AVCodecContext *s, AVFrame *frame);

#endif /* FFMPEG_DXVA2_H */

int dxva2_init(AVCodecContext *s, HWND hwnd);
int dxva2_retrieve_data_call(AVCodecContext *s, AVFrame *frame);

static int dxva2_retrieve_data(AVCodecContext *s, AVFrame *frame)
{
    LPDIRECT3DSURFACE9 surface = (LPDIRECT3DSURFACE9)frame->data[3];
    InputStream        *ist = (InputStream *)s->opaque;
    DXVA2Context       *ctx = (DXVA2Context *)ist->hwaccel_ctx;

    EnterCriticalSection(&cs);
    //直接渲染
    ctx->d3d9device->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
    ctx->d3d9device->BeginScene();
    if (m_pBackBuffer)
    {
        m_pBackBuffer->Release();
        m_pBackBuffer = NULL;
    }
    ctx->d3d9device->GetBackBuffer(0, 0, D3DBACKBUFFER_TYPE_MONO, &m_pBackBuffer);
    GetClientRect(d3dpp.hDeviceWindow, &m_rtViewport);
    ctx->d3d9device->StretchRect(surface, NULL, m_pBackBuffer, &m_rtViewport, D3DTEXF_LINEAR);
    ctx->d3d9device->EndScene();
    ctx->d3d9device->Present(NULL, NULL, NULL, NULL);

    LeaveCriticalSection(&cs);

    return 0;
}

switch (codec->id)
  {
  case AV_CODEC_ID_MPEG2VIDEO:
  case AV_CODEC_ID_H264:
  case AV_CODEC_ID_VC1:
  case AV_CODEC_ID_WMV3:
  case AV_CODEC_ID_HEVC:
  case AV_CODEC_ID_VP9:
    {
        codecctx->thread_count = 1;  // Multithreading is apparently not compatible with hardware decoding
        InputStream *ist = new InputStream();
        ist->hwaccel_id = HWACCEL_AUTO;
        ist->active_hwaccel_id = HWACCEL_AUTO;
        ist->hwaccel_device = "dxva2";
        ist->dec = codec;
        ist->dec_ctx = codecctx;

        codecctx->opaque = ist;
        if (dxva2_init(codecctx, hWnd) == 0)
        {
            codecctx->get_buffer2 = ist->hwaccel_get_buffer;
            codecctx->get_format = GetHwFormat;
            codecctx->thread_safe_callbacks = 1;

            break;
        }

        bAccel = false;
        break;
    }
  default:
      bAccel = false;
      break;
  }

if (pkt.stream_index == videoindex)
 {
  int got_picture = 0;

  DWORD t_start = GetTickCount();
  int bytes_used = avcodec_decode_video2(codecctx, picture, &got_picture, &pkt);
  if (got_picture)
  {
      if (bAccel)
      {
          //获取数据同时渲染
          dxva2_retrieve_data_call(codecctx, picture);

          DWORD t_end = GetTickCount();
          printf("dxva2 time using: %lu\n", t_end - t_start);
      }
      else
      {
          //非dxva2情形
          if (img_convert_ctx &&pFrameBGR && out_buffer)
          {
              //转换数据并渲染
              sws_scale(img_convert_ctx, (const uint8_t* const*)picture->data, picture->linesize, 0, codecctx->height, pFrameBGR->data, pFrameBGR->linesize);
              m_D3DVidRender.Render_YUV(out_buffer, picture->width, picture->height);

              DWORD t_end = GetTickCount();
              printf("normal time using: %lu\n", t_end - t_start);
          }
      }

      count++;
  }

  av_packet_unref(&pkt);
 }