avcodec: add D3D12VA hardware accelerated H264 decoding

The implementation is based on:
https://learn.microsoft.com/en-us/windows/win32/medfound/direct3d-12-video-overview

With the Direct3D 12 video decoding support, we can render or process
the decoded images by the pixel shaders or compute shaders directly
without the extra copy overhead, which is beneficial especially if you
are trying to render or post-process a 4K or 8K video.

The command below is how to enable d3d12va:
ffmpeg -hwaccel d3d12va -i input.mp4 output.mp4

Signed-off-by: Wu Jianhua <toqsxw@outlook.com>
Signed-off-by: Tong Wu <tong1.wu@intel.com>

1 files changed, 14 insertions, 12 deletions

diff --git a/libavcodec/dxva2_h264.c b/libavcodec/dxva2_h264.c
index 20e64f848d..e0ec4878a7 100644
--- a/libavcodec/dxva2_h264.c
+++ b/libavcodec/dxva2_h264.c
@@ -48,19 +48,16 @@ static void fill_picture_entry(DXVA_PicEntry_H264 *pic,
     pic->bPicEntry = index | (flag << 7);
 }
 
-static void fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *ctx, const H264Context *h,
+void ff_dxva2_h264_fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *ctx,
                                     DXVA_PicParams_H264 *pp)
 {
+    const H264Context *h               = avctx->priv_data;
     const H264Picture *current_picture = h->cur_pic_ptr;
     const SPS *sps = h->ps.sps;
     const PPS *pps = h->ps.pps;
     int i, j;
 
     memset(pp, 0, sizeof(*pp));
-    /* Configure current picture */
-    fill_picture_entry(&pp->CurrPic,
-                       ff_dxva2_get_surface_index(avctx, ctx, current_picture->f),
-                       h->picture_structure == PICT_BOTTOM_FIELD);
     /* Configure the set of references */
     pp->UsedForReferenceFlags  = 0;
     pp->NonExistingFrameFlags  = 0;
@@ -75,7 +72,7 @@ static void fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *
         }
         if (r) {
             fill_picture_entry(&pp->RefFrameList[i],
-                               ff_dxva2_get_surface_index(avctx, ctx, r->f),
+                               ff_dxva2_get_surface_index(avctx, ctx, r->f, 0),
                                r->long_ref != 0);
 
             if ((r->reference & PICT_TOP_FIELD) && r->field_poc[0] != INT_MAX)
@@ -95,6 +92,10 @@ static void fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *
             pp->FrameNumList[i]           = 0;
         }
     }
+    /* Configure current picture */
+    fill_picture_entry(&pp->CurrPic,
+                       ff_dxva2_get_surface_index(avctx, ctx, current_picture->f, 1),
+                       h->picture_structure == PICT_BOTTOM_FIELD);
 
     pp->wFrameWidthInMbsMinus1        = h->mb_width  - 1;
     pp->wFrameHeightInMbsMinus1       = h->mb_height - 1;
@@ -164,9 +165,10 @@ static void fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *
     //pp->SliceGroupMap[810];               /* XXX not implemented by FFmpeg */
 }
 
-static void fill_scaling_lists(const AVCodecContext *avctx, AVDXVAContext *ctx, const H264Context *h, DXVA_Qmatrix_H264 *qm)
+void ff_dxva2_h264_fill_scaling_lists(const AVCodecContext *avctx, AVDXVAContext *ctx, DXVA_Qmatrix_H264 *qm)
 {
-    const PPS *pps = h->ps.pps;
+    const H264Context *h   = avctx->priv_data;
+    const PPS         *pps = h->ps.pps;
     unsigned i, j;
     memset(qm, 0, sizeof(*qm));
     if (DXVA_CONTEXT_WORKAROUND(avctx, ctx) & FF_DXVA2_WORKAROUND_SCALING_LIST_ZIGZAG) {
@@ -253,9 +255,9 @@ static void fill_slice_long(AVCodecContext *avctx, DXVA_Slice_H264_Long *slice,
                 unsigned plane;
                 unsigned index;
                 if (DXVA_CONTEXT_WORKAROUND(avctx, ctx) & FF_DXVA2_WORKAROUND_INTEL_CLEARVIDEO)
-                    index = ff_dxva2_get_surface_index(avctx, ctx, r->f);
+                    index = ff_dxva2_get_surface_index(avctx, ctx, r->f, 0);
                 else
-                    index = get_refpic_index(pp, ff_dxva2_get_surface_index(avctx, ctx, r->f));
+                    index = get_refpic_index(pp, ff_dxva2_get_surface_index(avctx, ctx, r->f, 0));
                 fill_picture_entry(&slice->RefPicList[list][i], index,
                                    sl->ref_list[list][i].reference == PICT_BOTTOM_FIELD);
                 for (plane = 0; plane < 3; plane++) {
@@ -454,10 +456,10 @@ static int dxva2_h264_start_frame(AVCodecContext *avctx,
     assert(ctx_pic);
 
     /* Fill up DXVA_PicParams_H264 */
-    fill_picture_parameters(avctx, ctx, h, &ctx_pic->pp);
+    ff_dxva2_h264_fill_picture_parameters(avctx, ctx, &ctx_pic->pp);
 
     /* Fill up DXVA_Qmatrix_H264 */
-    fill_scaling_lists(avctx, ctx, h, &ctx_pic->qm);
+    ff_dxva2_h264_fill_scaling_lists(avctx, ctx, &ctx_pic->qm);
 
     ctx_pic->slice_count    = 0;
     ctx_pic->bitstream_size = 0;