lavu/hwcontext_qsv: Add support for AV_PIX_FMT_BGRA.

RGB32(AV_PIX_FMT_BGRA on intel platforms) format may be used as overlay with alpha blending.
So add AV_PIX_FMT_BGRA format support.

One example of alpha blending overlay: ffmpeg -hwaccel qsv -c:v h264_qsv -i BA1_Sony_D.jsv
-filter_complex 'movie=lena-rgba.png,hwupload=extra_hw_frames=16[a];[0:v][a]overlay_qsv=x=10:y=10'
-c:v h264_qsv -y out.mp4

Rename RGB32 to be BGRA to make it clearer as Mark Thompson's suggestion.

V2: Add P010 format support else will introduce HEVC 10bit encoding regression.
    Thanks for LinJie's discovery.

Signed-off-by: Zhong Li <zhong.li@intel.com>
Verified-by: Fu, Linjie <linjie.fu@intel.com>

libavfilter/qsvvpp.c

@@ -142,7 +142,7 @@ static int pix_fmt_to_mfx_fourcc(int format)
         return MFX_FOURCC_NV12;
     case AV_PIX_FMT_YUYV422:
         return MFX_FOURCC_YUY2;
-    case AV_PIX_FMT_RGB32:
+    case AV_PIX_FMT_BGRA:
         return MFX_FOURCC_RGB4;
     }
 

libavutil/hwcontext_qsv.c

@@ -100,6 +100,7 @@ static const struct {
     uint32_t           fourcc;
 } supported_pixel_formats[] = {
     { AV_PIX_FMT_NV12, MFX_FOURCC_NV12 },
+    { AV_PIX_FMT_BGRA, MFX_FOURCC_RGB4 },
     { AV_PIX_FMT_P010, MFX_FOURCC_P010 },
     { AV_PIX_FMT_PAL8, MFX_FOURCC_P8   },
 };
@@ -751,6 +752,37 @@ static int qsv_transfer_data_child(AVHWFramesContext *ctx, AVFrame *dst,
     return ret;
 }
 
+static int map_frame_to_surface(const AVFrame *frame, mfxFrameSurface1 *surface)
+{
+    switch (frame->format) {
+    case AV_PIX_FMT_NV12:
+    case AV_PIX_FMT_P010:
+        surface->Data.Y  = frame->data[0];
+        surface->Data.UV = frame->data[1];
+        break;
+
+    case AV_PIX_FMT_YUV420P:
+        surface->Data.Y = frame->data[0];
+        surface->Data.U = frame->data[1];
+        surface->Data.V = frame->data[2];
+        break;
+
+    case AV_PIX_FMT_BGRA:
+        surface->Data.B = frame->data[0];
+        surface->Data.G = frame->data[0] + 1;
+        surface->Data.R = frame->data[0] + 2;
+        surface->Data.A = frame->data[0] + 3;
+        break;
+
+    default:
+        return MFX_ERR_UNSUPPORTED;
+    }
+    surface->Data.Pitch     = frame->linesize[0];
+    surface->Data.TimeStamp = frame->pts;
+
+    return 0;
+}
+
 static int qsv_transfer_data_from(AVHWFramesContext *ctx, AVFrame *dst,
                                   const AVFrame *src)
 {
@@ -796,11 +828,7 @@ static int qsv_transfer_data_from(AVHWFramesContext *ctx, AVFrame *dst,
     }
 
     out.Info = in->Info;
-    out.Data.PitchLow = dst->linesize[0];
+    map_frame_to_surface(dst, &out);
-    out.Data.Y        = dst->data[0];
-    out.Data.U        = dst->data[1];
-    out.Data.V        = dst->data[2];
-    out.Data.A        = dst->data[3];
 
     do {
         err = MFXVideoVPP_RunFrameVPPAsync(s->session_download, in, &out, NULL, &sync);
@@ -868,11 +896,7 @@ static int qsv_transfer_data_to(AVHWFramesContext *ctx, AVFrame *dst,
     }
 
     in.Info = out->Info;
-    in.Data.PitchLow = src->linesize[0];
+    map_frame_to_surface(src, &in);
-    in.Data.Y        = src->data[0];
-    in.Data.U        = src->data[1];
-    in.Data.V        = src->data[2];
-    in.Data.A        = src->data[3];
 
     do {
         err = MFXVideoVPP_RunFrameVPPAsync(s->session_upload, &in, out, NULL, &sync);