gstspu: Implement PGS rendering and alpha blending

Refactor the DVD subpicture compositing, switching it to 8-bit alpha
calculations. Reuse some of the resulting code to implement PGS
subpicture blending.

Implement parsing and collecting of composition objects properly, but
assuming a single active window and colour palette for now. I need more
PGS samples.

1 files changed, 56 insertions, 0 deletions

diff --git a/gst/dvdspu/gstspu-common.h b/gst/dvdspu/gstspu-common.h
new file mode 100644
index 000000000..206e88203
--- /dev/null
+++ b/gst/dvdspu/gstspu-common.h
@@ -0,0 +1,56 @@
+/* GStreamer DVD Sub-Picture Unit
+ * Copyright (C) 2007 Fluendo S.A. <info@fluendo.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+#ifndef __GSTSPU_COMMON_H__
+#define __GSTSPU_COMMON_H__
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+/* FIXME: Move this back to gstdvdspu.h when the renderers no longer use it: */
+typedef struct _GstDVDSpu      GstDVDSpu;
+
+typedef struct SpuState SpuState;
+typedef struct SpuColour SpuColour;
+typedef struct SpuRect SpuRect;
+
+/* Describe the limits of a rectangle */
+struct SpuRect {
+  gint16 left;
+  gint16 top;
+  gint16 right;
+  gint16 bottom;
+};
+
+/* Store a pre-multiplied colour value. The YUV fields hold the YUV values
+ * multiplied by the 8-bit alpha, to save computing it while rendering */
+struct SpuColour {
+  guint16 Y;
+  guint16 U;
+  guint16 V;
+  guint8 A;
+};
+
+void gstspu_clear_comp_buffers (SpuState * state);
+void gstspu_blend_comp_buffers (SpuState * state, guint8 * planes[3]);
+
+
+G_END_DECLS
+
+#endif /* __GSTSPU_COMMON_H__ */