lavc/qsvdec: add function ff_qsv_map_picstruct()

Signed-off-by: Zhong Li <zhong.li@intel.com>

libavcodec/qsv.c

@@ -245,6 +245,24 @@ int ff_qsv_find_surface_idx(QSVFramesContext *ctx, QSVFrame *frame)
     return AVERROR_BUG;
 }
 
+enum AVFieldOrder ff_qsv_map_picstruct(int mfx_pic_struct)
+{
+    enum AVFieldOrder field = AV_FIELD_UNKNOWN;
+    switch (mfx_pic_struct & 0xF) {
+    case MFX_PICSTRUCT_PROGRESSIVE:
+        field = AV_FIELD_PROGRESSIVE;
+        break;
+    case MFX_PICSTRUCT_FIELD_TFF:
+        field = AV_FIELD_TT;
+        break;
+    case MFX_PICSTRUCT_FIELD_BFF:
+        field = AV_FIELD_BB;
+        break;
+    }
+
+    return field;
+}
+
 enum AVPictureType ff_qsv_map_pictype(int mfx_pic_type)
 {
     enum AVPictureType type;

libavcodec/qsv_internal.h

@@ -95,6 +95,8 @@ int ff_qsv_level_to_mfx(enum AVCodecID codec_id, int level);
 int ff_qsv_map_pixfmt(enum AVPixelFormat format, uint32_t *fourcc);
 enum AVPictureType ff_qsv_map_pictype(int mfx_pic_type);
 
+enum AVFieldOrder ff_qsv_map_picstruct(int mfx_pic_struct);
+
 int ff_qsv_init_internal_session(AVCodecContext *avctx, mfxSession *session,
                                  const char *load_plugins);