vc1: implement {start,end}_frame() hooks.

Implement GstVaapiDecoder.start_frame() and end_frame() semantics so
that to create new VA context earlier and submit VA pictures to the
HW for decoding as soon as possible. i.e. don't wait for the next
frame to start decoding the previous one.

diff --git a/gst-libs/gst/vaapi/gstvaapidecoder_vc1.c b/gst-libs/gst/vaapi/gstvaapidecoder_vc1.c
index 7baf02eeb1bb9b8e4ac40a501f14e404521e4d02..3fe8a9799cf998b951d91454fa9c30b6672884fc 100644 (file)
--- a/gst-libs/gst/vaapi/gstvaapidecoder_vc1.c
+++ b/gst-libs/gst/vaapi/gstvaapidecoder_vc1.c
@@ -844,45 +844,18 @@ static GstVaapiDecoderStatus
 decode_frame(GstVaapiDecoderVC1 *decoder, GstVC1BDU *rbdu, GstVC1BDU *ebdu)
 {
     GstVaapiDecoderVC1Private * const priv = decoder->priv;
-    GstVC1SeqHdr * const seq_hdr = &priv->seq_hdr;
     GstVC1FrameHdr * const frame_hdr = &priv->frame_hdr;
     GstVC1ParserResult result;
-    GstVaapiPicture *picture;
+    GstVaapiPicture * const picture = priv->current_picture;
     GstVaapiSlice *slice;
-    GstVaapiDecoderStatus status;
     VASliceParameterBufferVC1 *slice_param;
 
-    status = ensure_context(decoder);
-    if (status != GST_VAAPI_DECODER_STATUS_SUCCESS) {
-        GST_DEBUG("failed to reset context");
-        return status;
-    }
-
-    if (priv->current_picture) {
-        status = decode_current_picture(decoder);
-        if (status != GST_VAAPI_DECODER_STATUS_SUCCESS)
-            return status;
-    }
-
-    picture = GST_VAAPI_PICTURE_NEW(VC1, decoder);
-    if (!picture) {
-        GST_DEBUG("failed to allocate picture");
-        return GST_VAAPI_DECODER_STATUS_ERROR_ALLOCATION_FAILED;
-    }
-    gst_vaapi_picture_replace(&priv->current_picture, picture);
-    gst_vaapi_picture_unref(picture);
-
-    if (!gst_vc1_bitplanes_ensure_size(priv->bitplanes, seq_hdr)) {
-        GST_DEBUG("failed to allocate bitplanes");
-        return GST_VAAPI_DECODER_STATUS_ERROR_ALLOCATION_FAILED;
-    }
-
     memset(frame_hdr, 0, sizeof(*frame_hdr));
     result = gst_vc1_parse_frame_header(
         rbdu->data + rbdu->offset,
         rbdu->size,
         frame_hdr,
-        seq_hdr,
+        &priv->seq_hdr,
         priv->bitplanes
     );
     if (result != GST_VC1_PARSER_OK) {
@@ -1263,6 +1236,44 @@ gst_vaapi_decoder_vc1_decode(GstVaapiDecoder *base_decoder,
     return GST_VAAPI_DECODER_STATUS_SUCCESS;
 }
 
+static GstVaapiDecoderStatus
+gst_vaapi_decoder_vc1_start_frame(GstVaapiDecoder *base_decoder,
+    GstVaapiDecoderUnit *unit)
+{
+    GstVaapiDecoderVC1 * const decoder = GST_VAAPI_DECODER_VC1(base_decoder);
+    GstVaapiDecoderVC1Private * const priv = decoder->priv;
+    GstVaapiDecoderStatus status;
+    GstVaapiPicture *picture;
+
+    status = ensure_context(decoder);
+    if (status != GST_VAAPI_DECODER_STATUS_SUCCESS) {
+        GST_DEBUG("failed to reset context");
+        return status;
+    }
+
+    picture = GST_VAAPI_PICTURE_NEW(VC1, decoder);
+    if (!picture) {
+        GST_DEBUG("failed to allocate picture");
+        return GST_VAAPI_DECODER_STATUS_ERROR_ALLOCATION_FAILED;
+    }
+    gst_vaapi_picture_replace(&priv->current_picture, picture);
+    gst_vaapi_picture_unref(picture);
+
+    if (!gst_vc1_bitplanes_ensure_size(priv->bitplanes, &priv->seq_hdr)) {
+        GST_DEBUG("failed to allocate bitplanes");
+        return GST_VAAPI_DECODER_STATUS_ERROR_ALLOCATION_FAILED;
+    }
+    return GST_VAAPI_DECODER_STATUS_SUCCESS;
+}
+
+static GstVaapiDecoderStatus
+gst_vaapi_decoder_vc1_end_frame(GstVaapiDecoder *base_decoder)
+{
+    GstVaapiDecoderVC1 * const decoder = GST_VAAPI_DECODER_VC1(base_decoder);
+
+    return decode_current_picture(decoder);
+}
+
 static void
 gst_vaapi_decoder_vc1_finalize(GObject *object)
 {
@@ -1300,6 +1311,8 @@ gst_vaapi_decoder_vc1_class_init(GstVaapiDecoderVC1Class *klass)
 
     decoder_class->parse        = gst_vaapi_decoder_vc1_parse;
     decoder_class->decode       = gst_vaapi_decoder_vc1_decode;
+    decoder_class->start_frame  = gst_vaapi_decoder_vc1_start_frame;
+    decoder_class->end_frame    = gst_vaapi_decoder_vc1_end_frame;
 }
 
 static void