gstvdpvideosrcpad: add "template-caps" property

The property limits the available output caps

sys/vdpau/gstvdpmpegdec.c

@@ -1085,7 +1085,7 @@ gst_vdp_mpeg_dec_base_init (gpointer gclass)
   gst_element_class_add_pad_template (element_class,
       gst_static_pad_template_get (&sink_template));
 
-  src_caps = gst_vdp_video_src_pad_get_template_caps ();
+  src_caps = gst_vdp_video_buffer_get_caps (TRUE, VDP_CHROMA_TYPE_420);
   src_template = gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
       src_caps);
 
@@ -1133,7 +1133,15 @@ gst_vdp_mpeg_dec_init_info (VdpPictureInfoMPEG1Or2 * vdp_info)
 static void
 gst_vdp_mpeg_dec_init (GstVdpMpegDec * mpeg_dec, GstVdpMpegDecClass * gclass)
 {
-  mpeg_dec->src = GST_PAD (gst_vdp_video_src_pad_new ());
+  GstPadTemplate *src_template;
+
+  /* SRC PAD */
+  src_template =
+      gst_element_class_get_pad_template (GST_ELEMENT_CLASS (gclass), "src");
+  mpeg_dec->src =
+      GST_PAD (gst_vdp_video_src_pad_new (gst_pad_template_get_caps
+          (src_template)));
+
   gst_pad_set_event_function (mpeg_dec->src,
       GST_DEBUG_FUNCPTR (gst_vdp_mpeg_dec_src_event));
   gst_pad_set_query_function (mpeg_dec->src,

sys/vdpau/gstvdpvideosrcpad.c

@@ -28,7 +28,8 @@ GST_DEBUG_CATEGORY_STATIC (gst_vdp_video_src_pad_debug);
 enum
 {
   PROP_0,
-  PROP_DISPLAY
+  PROP_DISPLAY,
+  PROP_TEMPL_CAPS
 };
 
 #define DEBUG_INIT(bla) \
@@ -73,8 +74,10 @@ gst_vdp_video_src_pad_push (GstVdpVideoSrcPad * vdp_pad,
     }
 
     if (!gst_caps_is_equal_fixed (caps, GST_BUFFER_CAPS (out_buf))) {
-      GST_ERROR_OBJECT (vdp_pad, "Couldn't calculate buffer size for caps");
+      GST_ERROR_OBJECT (vdp_pad,
+          "Sink element allocated buffer with different caps");
       gst_buffer_unref (GST_BUFFER_CAST (video_buf));
+      gst_buffer_unref (out_buf);
       return GST_FLOW_ERROR;
     }
 
@@ -83,7 +86,8 @@ gst_vdp_video_src_pad_push (GstVdpVideoSrcPad * vdp_pad,
       GST_ERROR_OBJECT (vdp_pad,
           "Couldn't convert from GstVdpVideoBuffer to the requested format");
       gst_buffer_unref (GST_BUFFER_CAST (video_buf));
-      gst_buffer_unref (GST_BUFFER_CAST (out_buf));
+      gst_buffer_unref (out_buf);
+      return GST_FLOW_ERROR;
     }
 
     gst_buffer_copy_metadata (out_buf, (const GstBuffer *) video_buf,
@@ -100,17 +104,21 @@ gst_vdp_video_src_pad_push (GstVdpVideoSrcPad * vdp_pad,
 static void
 gst_vdp_video_src_pad_update_caps (GstVdpVideoSrcPad * vdp_pad)
 {
-  GstCaps *yuv_caps, *video_caps, *caps;
+  GstCaps *yuv_caps, *video_caps;
 
   video_caps = gst_vdp_video_buffer_get_allowed_video_caps (vdp_pad->device);
   yuv_caps = gst_vdp_video_buffer_get_allowed_yuv_caps (vdp_pad->device);
   gst_caps_append (video_caps, yuv_caps);
-  caps = gst_caps_intersect (video_caps, vdp_pad->caps);
 
-  gst_caps_unref (video_caps);
 
-  gst_caps_unref (vdp_pad->caps);
+  if (vdp_pad->caps)
-  vdp_pad->caps = caps;
+    gst_caps_unref (vdp_pad->caps);
+
+  if (vdp_pad->templ_caps) {
+    vdp_pad->caps = gst_caps_intersect (video_caps, vdp_pad->templ_caps);
+    gst_caps_unref (video_caps);
+  } else
+    vdp_pad->caps = video_caps;
 }
 
 GstFlowReturn
@@ -219,18 +227,17 @@ gst_vdp_video_src_pad_get_device (GstVdpVideoSrcPad * vdp_pad)
   return vdp_pad->device;
 }
 
-GstCaps *
-gst_vdp_video_src_pad_get_template_caps ()
-{
-  return gst_vdp_video_buffer_get_caps (TRUE, VDP_CHROMA_TYPE_420);
-}
-
 static GstCaps *
 gst_vdp_video_src_pad_getcaps (GstPad * pad)
 {
   GstVdpVideoSrcPad *vdp_pad = (GstVdpVideoSrcPad *) pad;
 
-  return gst_caps_ref (vdp_pad->caps);
+  if (vdp_pad->caps)
+    return gst_caps_ref (vdp_pad->caps);
+  else if (vdp_pad->templ_caps)
+    return gst_caps_ref (vdp_pad->templ_caps);
+
+  return NULL;
 }
 
 static gboolean
@@ -243,18 +250,19 @@ gst_vdp_video_src_pad_activate_push (GstPad * pad, gboolean active)
       g_object_unref (vdp_pad->device);
     vdp_pad->device = NULL;
 
-    gst_caps_unref (vdp_pad->caps);
+    if (vdp_pad->caps)
-    vdp_pad->caps = gst_vdp_video_buffer_get_caps (TRUE, VDP_CHROMA_TYPE_420);
+      gst_caps_unref (vdp_pad->caps);
+    vdp_pad->caps = NULL;
   }
 
   return TRUE;
 }
 
 GstVdpVideoSrcPad *
-gst_vdp_video_src_pad_new ()
+gst_vdp_video_src_pad_new (GstCaps * templ_caps)
 {
   return g_object_new (GST_TYPE_VDP_VIDEO_SRC_PAD, "direction", GST_PAD_SRC,
-      NULL);
+      "template-caps", templ_caps, NULL);
 }
 
 static void
@@ -267,6 +275,9 @@ gst_vdp_video_src_pad_get_property (GObject * object, guint prop_id,
     case PROP_DISPLAY:
       g_value_set_string (value, vdp_pad->display);
       break;
+    case PROP_TEMPL_CAPS:
+      gst_value_set_caps (value, vdp_pad->templ_caps);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -283,6 +294,11 @@ gst_vdp_video_src_pad_set_property (GObject * object, guint prop_id,
     case PROP_DISPLAY:
       vdp_pad->display = g_value_dup_string (value);
       break;
+    case PROP_TEMPL_CAPS:
+      if (vdp_pad->templ_caps)
+        gst_caps_unref (vdp_pad->templ_caps);
+      vdp_pad->templ_caps = gst_caps_copy (gst_value_get_caps (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -295,6 +311,8 @@ gst_vdp_video_src_pad_finalize (GObject * object)
   GstVdpVideoSrcPad *vdp_pad = (GstVdpVideoSrcPad *) object;
 
   g_free (vdp_pad->display);
+  if (vdp_pad->templ_caps)
+    gst_caps_unref (vdp_pad->templ_caps);
 
   G_OBJECT_CLASS (gst_vdp_video_src_pad_parent_class)->finalize (object);
 }
@@ -305,9 +323,10 @@ gst_vdp_video_src_pad_init (GstVdpVideoSrcPad * vdp_pad)
   GstPad *pad = GST_PAD (vdp_pad);
 
   vdp_pad->device = NULL;
-  vdp_pad->display = NULL;
+  vdp_pad->caps = NULL;
 
-  vdp_pad->caps = gst_vdp_video_buffer_get_caps (TRUE, VDP_CHROMA_TYPE_420);
+  vdp_pad->display = NULL;
+  vdp_pad->templ_caps = NULL;
 
   gst_pad_set_getcaps_function (pad,
       GST_DEBUG_FUNCPTR (gst_vdp_video_src_pad_getcaps));
@@ -328,4 +347,9 @@ gst_vdp_video_src_pad_class_init (GstVdpVideoSrcPadClass * klass)
       g_param_spec_string ("display", "Display", "X Display name",
           NULL, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
 
+  g_object_class_install_property (object_class, PROP_TEMPL_CAPS,
+      g_param_spec_boxed ("template-caps", "Template caps",
+          "Template caps", GST_TYPE_CAPS,
+          G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+
 }

sys/vdpau/gstvdpvideosrcpad.h

@@ -51,6 +51,7 @@ struct _GstVdpVideoSrcPad
 
   /* properties */
   gchar *display;
+  GstCaps *templ_caps;
 };
 
 struct _GstVdpVideoSrcPadClass
@@ -67,7 +68,7 @@ gboolean gst_vdp_video_src_pad_set_caps (GstVdpVideoSrcPad *vdp_pad, GstCaps *ca
 
 GstCaps *gst_vdp_video_src_pad_get_template_caps ();
 
-GstVdpVideoSrcPad *gst_vdp_video_src_pad_new ();
+GstVdpVideoSrcPad *gst_vdp_video_src_pad_new (GstCaps *templ_caps);
 GType gst_vdp_video_src_pad_get_type (void) G_GNUC_CONST;
 
 G_END_DECLS