qsv{enc,dec}: extend the internal frame allocator

Handle the internal frame requests, which is required by the HEVC
encoding plugin.
Signed-off-by: Maxym Dmytrychenko <maxym.dmytrychenko@intel.com>

libavcodec/qsv_internal.h

@@ -37,7 +37,12 @@
      MFX_VERSION_MAJOR == (MAJOR) && MFX_VERSION_MINOR >= (MINOR))
 
 typedef struct QSVMid {
+    AVBufferRef *hw_frames_ref;
     mfxHDL handle;
+
+    AVFrame *locked_frame;
+    AVFrame *hw_frame;
+    mfxFrameSurface1 surf;
 } QSVMid;
 
 typedef struct QSVFrame {
@@ -52,7 +57,13 @@ typedef struct QSVFrame {
 
 typedef struct QSVFramesContext {
     AVBufferRef *hw_frames_ctx;
-    mfxFrameInfo info;
+    void *logctx;
+
+    /* The memory ids for the external frames.
+     * Refcounted, since we need one reference owned by the QSVFramesContext
+     * (i.e. by the encoder/decoder) and another one given to the MFX session
+     * from the frame allocator. */
+    AVBufferRef *mids_buf;
     QSVMid *mids;
     int  nb_mids;
 } QSVFramesContext;

libavcodec/qsvdec.c

@@ -416,8 +416,7 @@ int ff_qsv_decode_close(QSVContext *q)
         MFXClose(q->internal_session);
 
     av_buffer_unref(&q->frames_ctx.hw_frames_ctx);
-    av_freep(&q->frames_ctx.mids);
-    q->frames_ctx.nb_mids = 0;
+    av_buffer_unref(&q->frames_ctx.mids_buf);
 
     return 0;
 }

libavcodec/qsvenc.c

@@ -1093,8 +1093,7 @@ int ff_qsv_enc_close(AVCodecContext *avctx, QSVEncContext *q)
     q->internal_session = NULL;
 
     av_buffer_unref(&q->frames_ctx.hw_frames_ctx);
-    av_freep(&q->frames_ctx.mids);
-    q->frames_ctx.nb_mids = 0;
+    av_buffer_unref(&q->frames_ctx.mids_buf);
 
     cur = q->work_frames;
     while (cur) {